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2025-12-31 0001026144 bifi:ClassKMember bifi:S000003118Russell2000IndexMember 2016-01-01 2025-12-31 0001026144 bifi:ClassKMember bifi:S000003118Russell3000IndexMember 2016-01-01 2025-12-31 0001026144 bifi:InvestorAInstitutionalMember bifi:S000003116MSCIEAFEIndexEuropeAustralasiaFarEastNetMember 2016-01-01 2025-12-31 0001026144 bifi:InvestorAInstitutionalMember bifi:S000003118Russell2000IndexMember 2016-01-01 2025-12-31 0001026144 bifi:InvestorAInstitutionalMember bifi:S000003118Russell3000IndexMember 2016-01-01 2025-12-31 0001026144 bifi:InvestorPSharesMember bifi:S000003116MSCIEAFEIndexMember 2016-01-01 2025-12-31 0001026144 bifi:InvestorPSharesMember bifi:S000003118Russell2000IndexMember 2016-01-01 2025-12-31 0001026144 bifi:InvestorPSharesMember bifi:S000003118Russell3000IndexMember 2016-01-01 2025-12-31 iso4217:USD pure 0001026144 false 485BPOS 2025-12-31 0.1250 0.1966 0.2104 0.1435 -0.1119 0.2520 0.1438 -0.2057 0.1660 0.1115 -0.1436 0.1802 0.0339 0.3139 0.0078 0.2484 -0.1357 0.2153 0.0768 0.1101 0.2132 0.1469 -0.1093 0.2562 0.2000 0.1478 -0.2032 0.1695 0.1147 0.1283 0.0807 0.1133 -0.1407 0.1834 0.0373 0.3173 -0.1333 0.0103 0.2194 0.2517 0.2103 0.1427 -0.1119 0.2525 0.1965 0.1442 -0.2057 0.1662 0.1114 0.1247 0.0074 0.2493 -0.1357 0.2151 0.0768 0.1105 -0.1436 0.1792 0.0346 0.3130 -0.1337 0.0099 0.2524 0.1128 0.2180 0.0803 -0.1418 0.1832 0.0375 0.3176 N-1A BlackRock Index Funds, Inc. 2026-04-30 Fund Overview Key Facts About iShares Russell 2000 Small-Cap Index Fund Investment Objective <div style="margin-top: 6pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">The investment objective of iShares Russell 2000 Small-Cap Index Fund (“Russell 2000 Small-Cap Index Fund”or the </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">“Fund”), a series of BlackRock Index Funds, Inc. (the “Corporation”), is to match the performance of the Russell </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">2000</span><span style="color: #000000; font-family: arial; font-size: 5pt; position: relative; top: -3.25pt;">®</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;"> Index (the “Russell 2000” or the </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">“</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Underlying Index</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">”</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">) as closely as possible before the deduction of Fund </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">expenses.</span></div> Fees and Expenses of the Fund <div style="margin-top: 6pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">This table describes the fees and expenses that you may pay if you buy, hold and sell shares of Russell 2000 Small-Cap</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;"> Index Fund. </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">You may pay other fees, such as brokerage commissions and other fees to your financial </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">professional or your selected securities dealer, broker, investment adviser, service provider or industry professional </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">(including BlackRock Advisors, LLC (</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">“</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">BlackRock</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">”</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">) and its affiliates) (each, a </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">“</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">Financial Intermediary</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">”</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">), which are </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-weight: bold;">not reflected in the table and example below.</span><span style="color: #000000; font-family: arial; font-size: 1pt; line-height: 0.93pt;"> </span></div> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0001 0.0001 0.0025 0 0.0015 0.0012 0.0004 0.0004 0.0011 0.0008 0.0041 0.0013 -0.0004 -0.0001 0.0037 0.0012 June 30, 2027 The Total Annual Fund Operating Expenses and Miscellaneous Other Expenses do not correlate to the ratios of expenses to average net assetsgiven in the Fund’s most recent Annual Financial Statements and Additional Information report, which do not include Acquired Fund Fees andExpenses. Example: <div style="line-height: 10.695pt; text-align: left;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% </span></div> <div style="line-height: 10.695pt; text-align: left;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">or lower, based on these assumptions your costs would be:</span><span style="color: #000000; font-family: arial; font-size: 1pt; line-height: 0.93pt;"> </span></div> 38 128 226 514 12 41 72 165 Portfolio Turnover: <div style="line-height: 10.695pt; margin-top: 0.0pt; text-align: left;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">The Series pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Example, affect the Fund’s performance. During the most recent fiscal year, the Series’ portfolio turnover rate was </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">21</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">% of the average value of its portfolio.</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; line-height: 10.695pt;"> </span></div> 0.21 Principal Investment Strategies of the Fund <div style="margin-top: 6pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Russell 2000 Small-Cap Index Fund employs a “passive” management approach, attempting to invest in a portfolio of </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">assets whose performance is expected to match approximately the performance of the Russell 2000. The Fund will be </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">substantially invested in securities in the Russell 2000, and will invest, under normal circumstances, at least 80% of </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">its assets in securities or other financial instruments that are components of or have economic characteristics similar </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">to the securities included in the Russell 2000. The Fund may change its target index if Fund management believes a </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">different index would better enable the Fund to match the performance of the market segment represented by the </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">current index.</span></div> <div style="margin-top: 6pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">The Fund may invest in a statistically selected sample of stocks included in the Russell 2000 and in derivative </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">instruments linked to the Russell 2000. The Fund may not invest in all of the common stocks in the Russell 2000, or </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">in the same weightings as in the Russell 2000. The Fund chooses investments so that the market capitalizations, </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">industry weightings and other fundamental characteristics of the stocks and derivative instruments chosen are similar </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">to the Russell 2000 as a whole. As of March 31, 2026, the companies in the Russell 2000 have a market </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">capitalization ranging from $3.29 million to $39.25 billion.</span></div> <div style="margin-top: 6pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">The Fund is a “feeder” fund that invests all of its assets in the Series, a series of the Master LLC, which has the same </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">investment objective and strategies as the Fund. All investments are made at the Series level. This structure is </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">sometimes called a “master/feeder” structure. The Fund’s investment results will correspond directly to the </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">investment results of the Series. For simplicity, this prospectus uses the name of the Fund or the term “Fund” (as </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">applicable) to include the Series.</span></div> You maylose part or all of your investment in the Fund or your investment may not perform as well as other similarinvestments. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div> <div style="clear: both; margin-top: 4.805pt; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.00pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Small Cap Securities Risk </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic;">—</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;"> Small cap companies may have limited product lines or markets. They may be less </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">financially secure than larger, more established companies. They may depend on a more limited management group </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">than larger capitalized companies.</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; line-height: 10.695pt;"> </span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.805pt; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.00pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Index-Related Risk </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">— The index provider may rely on various sources of information to assess the criteria of </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">components of the Underlying Index, including information that may be based on assumptions and estimates. </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Neither the Fund nor BlackRock can offer assurances that the index provider’s methodology or sources of </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">information will provide an accurate assessment of included components. Errors in index data, index computations </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">or the construction of the Underlying Index in accordance with its methodology may occur, and the index provider </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">may not identify or correct them promptly or at all, which may have an adverse impact on the Fund and its </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">unrest or war) may impact the index provider or a third-party data provider and could cause the index provider to </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">postpone a scheduled rebalance. This could cause the Underlying Index to vary from its normal or expected </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">composition.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.00pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Passive Investment Risk </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic;">—</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;"> Because BlackRock does not select individual companies in the index that the Fund </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">tracks, the Fund may hold securities of companies that present risks that an investment adviser researching </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">individual securities might seek to avoid.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.805pt; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.00pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Tracking Error Risk </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">— The Fund is subject to the risk of “tracking error,” which is the divergence of the Fund’s </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">performance from that of the Underlying Index. Tracking error may occur due to a number of factors, including </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">differences between the securities and other assets held in the Fund’s portfolio and those included in the </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Underlying Index; differences in the timing and methodologies used to value securities and other assets; </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">transaction costs and other expenses incurred by the Fund that the Underlying Index does not incur; the Fund’s </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">holding of uninvested cash; differences in the timing of the accrual or the valuation of dividends or interest received </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">by the Fund or distributions paid to Fund shareholders; tax gains or losses; differences between the amount and/or </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">timing of withholding taxes on dividends reflected in the Underlying Index from the Fund’s obligation, if any, for </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">foreign withholding taxes; the requirements for the Fund to maintain pass-through tax treatment; portfolio </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">transactions carried out to minimize the distribution of capital gains to shareholders; changes to the Underlying </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Index, such as during a rebalancing or reconstitution; and impacts to the Fund of complying with certain regulatory </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">requirements or limits. A fund that tracks an index composed of a large number of securities or other assets may </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">experience greater tracking error than a fund that tracks a more narrow index. Tracking error risk may be heightened </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">during times of increased market volatility or other unusual market conditions.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.805pt; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.00pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Equity Securities Risk </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">— Stock markets are volatile. The price of equity securities fluctuates based on changes in a </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">company’s financial condition and overall market and economic conditions.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.805pt; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.00pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Market Risk and Selection Risk </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">— Market risk is the risk that one or more markets in which the Fund invests will </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">security or other asset may decline due to changes in general market conditions, economic trends or events that </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">investments. Selection risk is the risk that the securities selected by Fund management will underperform the </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">markets, the relevant indices or the securities selected by other funds with similar investment objectives and </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">investment strategies. This means you may lose money.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.805pt; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.00pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Operational and Technology Risks </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">— The Fund is directly and indirectly susceptible to operational and technology </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">risks, including those related to human errors, processing errors, communication errors, systems failures, </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">for the Fund and its shareholders or may impair the Fund’s operations. While the Fund’s service providers are </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">required to have appropriate operational, information security and cybersecurity risk management policies and </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">may cause the Fund’s investments in such issuers to lose value.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.805pt; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.0pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Representative Sampling Risk</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; line-height: 10.695pt;"> </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic;">—</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;"> Representative sampling is a method of indexing that involves investing in a </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">representative sample of securities that collectively have a similar investment profile to the Underlying Index and </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">resemble the Underlying Index in terms of risk factors and other key characteristics. The Fund may or may not hold </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">every security in the Underlying Index. When the Fund deviates from a full replication indexing strategy to utilize a </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">representative sampling strategy, the Fund is subject to an increased risk of tracking error, in that the securities </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">selected in the aggregate for the Fund may not have an investment profile similar to those of the Underlying Index.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.805pt; position: relative; width: 100%;"> <div style="float: left; line-height: 9.87pt; text-align: left; width: 8pt;"><span style="color: #000000; font-family: arial; font-size: 8.37pt; position: relative; top: -0.5pt;">◼</span></div> <div style="float: left; line-height: 10.80pt; margin-left: 4pt; text-align: left; width: 505.00pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic; font-weight: bold;">Risk of Investing in the United States </span><span style="color: #000000; font-family: arial; font-size: 9.30pt; font-style: italic;">—</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;"> Certain changes in the U.S. economy, such as when the U.S. economy </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">exposure.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> Performance Information <div style="margin-top: 6pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">The information shows you how the Fund’s performance has varied year by year and provides some indication of the</span> <span style="color: #000000; font-family: arial; font-size: 9.30pt;">risks of investing in the Fund. The table compares the Fund’s performance to that of the Russell 3000</span><span style="color: #000000; font-family: arial; font-size: 5pt; position: relative; top: -3.25pt;">® </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Index and the </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">Russell 2000. The Russell 2000 is relevant to the Fund because it has characteristics similar to the Fund’s </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">investment strategy. To the extent that dividends and distributions have been paid by the Fund, the performance</span> <span style="color: #000000; font-family: arial; font-size: 9.30pt;">information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all</span> <span style="color: #000000; font-family: arial; font-size: 9.30pt;">such investments, past performance (before and after taxes) is not an indication of future results. The table includes </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">all applicable fees. If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s </span></div> <div style="line-height: 10.695pt; text-align: left;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">performance, including its current net asset value, can be obtained by visiting www.blackrock.com or can be obtained </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">by phone at </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">(800) 882-0052</span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">.</span></div> The information shows you how the Fund’s performance has varied year by year and provides some indication of therisks of investing in the Fund. As with allsuch investments, past performance (before and after taxes) is not an indication of future results. www.blackrock.com (800) 882-0052 Investor A Shares ANNUAL TOTAL RETURNS Russell 2000 Small-Cap Index Fund As of 12/31 <div style="margin-top: 6pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">During the ten-year period shown in the bar chart, the highest return for a quarter was 31.27% (quarter ended </span><span style="color: #000000; font-family: arial; font-size: 9.30pt;">December 31, 2020) and the lowest return for a quarter was -30.60% (quarter ended March 31, 2020).</span><span style="color: #000000; font-family: arial; font-size: 9.30pt; line-height: 10.695pt;"> </span><span style="color: #000000; font-family: arial; font-size: 1pt; line-height: 0.93pt;"> </span></div> highest return 0.3127 2020-12-31 lowest return -0.3060 2020-03-31 For the periods ended 12/31/25Average Annual Total Returns 0.1250 0.0578 0.0933 0.1158 0.0473 0.0832 0.0777 0.0428 0.0733 0.1278 0.0605 0.0960 0.1715 0.1315 0.1429 0.1281 0.0609 0.0962 <div style="margin-top: 12pt;"><span style="color: #000000; font-family: arial; font-size: 9.30pt;">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not</span> <span style="color: #000000; font-family: arial; font-size: 9.30pt;">reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may</span> <span style="color: #000000; font-family: arial; font-size: 9.30pt;">differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through</span> <span style="color: #000000; font-family: arial; font-size: 9.30pt;">tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for</span> <span style="color: #000000; font-family: arial; font-size: 9.30pt;">Investor A Shares only, and the after-tax returns for Institutional Shares will vary.</span></div> After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do notreflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and maydiffer from those shown, and the after-tax returns shown are not relevant to investors who hold their shares throughtax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown forInvestor A Shares only, and the after-tax returns for Institutional Shares will vary. Fund Overview Key Facts About iShares MSCI EAFE International Index Fund Investment Objective <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The investment objective of iShares MSCI EAFE International Index Fund (“MSCI EAFE International Index Fund”or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“Fund”), a series of BlackRock Index Funds, Inc. (the “Corporation”), is to match the performance of the MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index (Europe, Australasia, Far East) (the “MSCI EAFE Index” or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">) in U.S. dollars with net </span><span style="color:#000000;font-family:arial;font-size:9.30pt">dividends as closely as possible before the deduction of Fund expenses.</span></div> Fees and Expenses of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This table describes the fees and expenses that you may pay if you buy, hold and sell shares of MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">International Index Fund. </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">You may pay other fees, such as brokerage commissions and other fees to your financial </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">professional or your selected securities dealer, broker, investment adviser, service provider or industry professional </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">(including BlackRock Advisors, LLC (</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">BlackRock</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">) and its affiliates) (each, a </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">Financial Intermediary</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">), which are </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">not reflected in the table and example below.</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0001 0.0001 0.0025 0 0.0008 0.0008 0.0008 0.0008 0.0034 0.0009 0.0034 0.0009 June 30, 2027 Example: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other </span><span style="color:#000000;font-family:arial;font-size:9.30pt">mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then </span><span style="color:#000000;font-family:arial;font-size:9.30pt">redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or lower, based on these assumptions your costs would be:</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> 35 109 191 431 9 29 51 115 Portfolio Turnover: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="color:#000000;font-family:arial;font-size:9.30pt">8</span><span style="color:#000000;font-family:arial;font-size:9.30pt">% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">of the average value of its portfolio.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> 0.08 Principal Investment Strategies of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund employs a “passive” management approach, attempting to invest in a portfolio of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">assets whose performance is expected to match approximately the performance of the MSCI EAFE Index. The Fund will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be substantially invested in securities in the MSCI EAFE Index, and will invest, under normal circumstances, at least </span><span style="color:#000000;font-family:arial;font-size:9.30pt">80% of its assets in securities or other financial instruments that are components of or have economic characteristics </span><span style="color:#000000;font-family:arial;font-size:9.30pt">similar to the securities included in the MSCI EAFE Index. The Fund may change its target index if Fund management </span><span style="color:#000000;font-family:arial;font-size:9.30pt">believes a different index would better enable the Fund to match the performance of the market segment represented </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the current index.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund invests in a statistically selected sample of equity securities included in the MSCI </span><span style="color:#000000;font-family:arial;font-size:9.30pt">EAFE Index and in derivative instruments linked to the MSCI EAFE Index. Equity securities include common stock, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">preferred stock and securities or other instruments whose price is linked to the value of common stock. The Fund will, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">under normal circumstances, invest in all of the countries represented in the MSCI EAFE Index. The Fund may not, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">however, invest in all of the companies within a country represented in the MSCI EAFE Index, or in the same weightings </span><span style="color:#000000;font-family:arial;font-size:9.30pt">as in the MSCI EAFE Index.</span></div> You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Equity Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Stock markets are volatile. The price of equity securities fluctuates based on changes in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">company’s financial condition and overall market and economic conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Foreign Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Foreign investments often involve special risks not present in U.S. investments that can </span><span style="color:#000000;font-family:arial;font-size:9.30pt">increase the chances that the Fund will lose money. These risks include:</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">oversight.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Changes in foreign currency exchange rates can affect the value of the Fund’s portfolio.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The economies of certain foreign markets may not compare favorably with the economy of the United States with </span><span style="color:#000000;font-family:arial;font-size:9.30pt">respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">payments position.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The governments of certain countries, or the U.S. Government with respect to certain countries, may prohibit or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer </span><span style="color:#000000;font-family:arial;font-size:9.30pt">currency, securities, derivatives or other assets.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the same extent as does the United States and may not have laws to protect investors that are comparable to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">U.S. securities laws.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">securities not typically associated with settlement and clearance of U.S. investments.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund’s claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div style="line-height:10.695pt;margin-left:24pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign country, accruals in the Fund’s net asset value for such refunds may be written down partially or in full, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">which will adversely affect the Fund’s net asset value.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Index-Related Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The index provider may rely on various sources of information to assess the criteria of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">components of the Underlying Index, including information that may be based on assumptions and estimates. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Neither the Fund nor BlackRock can offer assurances that the index provider’s methodology or sources of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">information will provide an accurate assessment of included components. Errors in index data, index computations </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or the construction of the Underlying Index in accordance with its methodology may occur, and the index provider </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may not identify or correct them promptly or at all, which may have an adverse impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political </span><span style="color:#000000;font-family:arial;font-size:9.30pt">unrest or war) may impact the index provider or a third-party data provider and could cause the index provider to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">postpone a scheduled rebalance. This could cause the Underlying Index to vary from its normal or expected </span><span style="color:#000000;font-family:arial;font-size:9.30pt">composition.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Large-Capitalization Companies Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> — Large-capitalization companies may be less able than smaller-capitalization </span><span style="color:#000000;font-family:arial;font-size:9.30pt">companies to adapt to changing market conditions and competitive challenges. Large-capitalization companies may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be more mature and subject to more limited growth potential compared with smaller-capitalization companies. The </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance of large-capitalization companies could trail the overall performance of the broader securities markets.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Passive Investment Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Because BlackRock does not select individual companies in the index that the Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tracks, the Fund may hold securities of companies that present risks that an investment adviser researching </span><span style="color:#000000;font-family:arial;font-size:9.30pt">individual securities might seek to avoid.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Small and Mid-Capitalization Company Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Companies with small or mid-size market capitalizations will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">normally have more limited product lines, markets and financial resources and will be dependent upon a more </span><span style="color:#000000;font-family:arial;font-size:9.30pt">limited management group than larger capitalized companies. In addition, it is more difficult to get information on </span><span style="color:#000000;font-family:arial;font-size:9.30pt">smaller companies, which tend to be less well known, have shorter operating histories, do not have significant </span><span style="color:#000000;font-family:arial;font-size:9.30pt">ownership by large investors and are followed by relatively few securities analysts.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Tracking Error Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is subject to the risk of “tracking error,” which is the divergence of the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance from that of the Underlying Index. Tracking error may occur due to a number of factors, including </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differences between the securities and other assets held in the Fund’s portfolio and those included in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index; differences in the timing and methodologies used to value securities and other assets; </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transaction costs and other expenses incurred by the Fund that the Underlying Index does not incur; the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">holding of uninvested cash; differences in the timing of the accrual or the valuation of dividends or interest received </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the Fund or distributions paid to Fund shareholders; tax gains or losses; differences between the amount and/or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">timing of withholding taxes on dividends reflected in the Underlying Index from the Fund’s obligation, if any, for </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes; the requirements for the Fund to maintain pass-through tax treatment; portfolio </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transactions carried out to minimize the distribution of capital gains to shareholders; changes to the Underlying </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index, such as during a rebalancing or reconstitution; and impacts to the Fund of complying with certain regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">requirements or limits. A fund that tracks an index composed of a large number of securities or other assets may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">experience greater tracking error than a fund that tracks a more narrow index. Tracking error risk may be heightened </span><span style="color:#000000;font-family:arial;font-size:9.30pt">during times of increased market volatility or other unusual market conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Market Risk and Selection Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Market risk is the risk that one or more markets in which the Fund invests will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">security or other asset may decline due to changes in general market conditions, economic trends or events that </span><span style="color:#000000;font-family:arial;font-size:9.30pt">are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investments. Selection risk is the risk that the securities selected by Fund management will underperform the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets, the relevant indices or the securities selected by other funds with similar investment objectives and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment strategies. This means you may lose money.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Operational and Technology Risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is directly and indirectly susceptible to operational and technology </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks, including those related to human errors, processing errors, communication errors, systems failures, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the Fund and its shareholders or may impair the Fund’s operations. While the Fund’s service providers are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">required to have appropriate operational, information security and cybersecurity risk management policies and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may cause the Fund’s investments in such issuers to lose value.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Representative Sampling Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Representative sampling is a method of indexing that involves investing in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sample of securities that collectively have a similar investment profile to the Underlying Index and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">resemble the Underlying Index in terms of risk factors and other key characteristics. The Fund may or may not hold </span><span style="color:#000000;font-family:arial;font-size:9.30pt">every security in the Underlying Index. When the Fund deviates from a full replication indexing strategy to utilize a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sampling strategy, the Fund is subject to an increased risk of tracking error, in that the securities </span><span style="color:#000000;font-family:arial;font-size:9.30pt">selected in the aggregate for the Fund may not have an investment profile similar to those of the Underlying Index.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> Performance Information <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The information shows you how the Fund’s performance has varied year by year and provides some indication of the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks of investing in the Fund. The table compares the Fund’s performance to that of the MSCI EAFE Index (Net). To the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance (before and after taxes) is not an indication of future results. The table includes all applicable fees. If the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these </span><span style="color:#000000;font-family:arial;font-size:9.30pt">periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance, including its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">current net asset value, can be obtained by visiting www.blackrock.com or can be obtained by phone at </span><span style="color:#000000;font-family:arial;font-size:9.30pt">(800) 882-0052</span><span style="color:#000000;font-family:arial;font-size:9.30pt">.</span></div> The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. As with all such investments, past performance (before and after taxes) is not an indication of future results. www.blackrock.com (800) 882-0052 Investor A Shares ANNUAL TOTAL RETURNS MSCI EAFE International Index Fund As of 12/31 <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">During the ten-year period shown in the bar chart, the highest return for a quarter was 18.07% (quarter ended </span><span style="color:#000000;font-family:arial;font-size:9.30pt">December 31, 2022) and the lowest return for a quarter was -23.37% (quarter ended March 31, 2020).</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> highest return 0.1807 2022-12-31 lowest return -0.2337 2020-03-31 For the periods ended 12/31/25Average Annual Total Returns 0.3139 0.0879 0.0805 0.3008 0.0810 0.0743 0.1909 0.0687 0.0648 0.3164 0.0905 0.0832 0.3122 0.0892 0.0818 <div style="margin-top:12pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not </span><span style="color:#000000;font-family:arial;font-size:9.30pt">reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Investor A Shares only, and the after-tax returns for Institutional Shares will vary.</span></div> After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Investor A Shares only, and the after-tax returns for Institutional Shares will vary. Fund Overview Key Facts About iShares Russell 2000 Small-Cap Index Fund Investment Objective <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The investment objective of iShares Russell 2000 Small-Cap Index Fund (“Russell 2000 Small-Cap Index Fund”or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“Fund”), a series of BlackRock Index Funds, Inc. (the “Corporation”), is to match the performance of the Russell </span><span style="color:#000000;font-family:arial;font-size:9.30pt">2000</span><span style="color:#000000;font-family:arial;font-size:5pt;position:relative;top:-3.25pt">®</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Index (the “Russell 2000” or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">) as closely as possible before the deduction of Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">expenses.</span></div> Fees and Expenses of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This table describes the fees and expenses that you may pay if you buy, hold and sell Class K Shares of Russell 2000 </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Small-Cap Index Fund. </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">You may pay other fees, such as brokerage commissions and other fees to your financial </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">professional or your selected securities dealer, broker, investment adviser, service provider or industry professional </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">(including BlackRock Advisors, LLC (</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">BlackRock</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">) and its affiliates) (each, a </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">Financial Intermediary</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">), which are </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">not reflected in the table and example below.</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0001 0 0.0006 0.0004 0.0002 0.0007 0.0007 June 30, 2027 Example: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other </span><span style="color:#000000;font-family:arial;font-size:9.30pt">mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then </span><span style="color:#000000;font-family:arial;font-size:9.30pt">redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or lower, based on these assumptions your costs would be:</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> 7 23 40 90 Portfolio Turnover: <div style="line-height:10.695pt;margin-top:0.0pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Series pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Example, affect the Fund’s performance. During the most recent fiscal year, the Series’ portfolio turnover rate was </span><span style="color:#000000;font-family:arial;font-size:9.30pt">21</span><span style="color:#000000;font-family:arial;font-size:9.30pt">% of the average value of its portfolio.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> 0.21 Principal Investment Strategies of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Russell 2000 Small-Cap Index Fund employs a “passive” management approach, attempting to invest in a portfolio of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">assets whose performance is expected to match approximately the performance of the Russell 2000. The Fund will be </span><span style="color:#000000;font-family:arial;font-size:9.30pt">substantially invested in securities in the Russell 2000, and will invest, under normal circumstances, at least 80% of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">its assets in securities or other financial instruments that are components of or have economic characteristics similar </span><span style="color:#000000;font-family:arial;font-size:9.30pt">to the securities included in the Russell 2000. The Fund may change its target index if Fund management believes a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">different index would better enable the Fund to match the performance of the market segment represented by the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">current index.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund may invest in a statistically selected sample of stocks included in the Russell 2000 and in derivative </span><span style="color:#000000;font-family:arial;font-size:9.30pt">instruments linked to the Russell 2000. The Fund may not invest in all of the common stocks in the Russell 2000, or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">in the same weightings as in the Russell 2000. The Fund chooses investments so that the market capitalizations, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">industry weightings and other fundamental characteristics of the stocks and derivative instruments chosen are similar </span><span style="color:#000000;font-family:arial;font-size:9.30pt">to the Russell 2000 as a whole. As of March 31, 2026, the companies in the Russell 2000 have a market </span><span style="color:#000000;font-family:arial;font-size:9.30pt">capitalization ranging from $3.29 million to $39.25 billion.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund is a “feeder” fund that invests all of its assets in the Series, a series of the Master LLC, which has the same </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment objective and strategies as the Fund. All investments are made at the Series level. This structure is </span><span style="color:#000000;font-family:arial;font-size:9.30pt">sometimes called a “master/feeder” structure. The Fund’s investment results will correspond directly to the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment results of the Series. For simplicity, this prospectus uses the name of the Fund or the term “Fund” (as </span><span style="color:#000000;font-family:arial;font-size:9.30pt">applicable) to include the Series.</span></div> You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Small Cap Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Small cap companies may have limited product lines or markets. They may be less </span><span style="color:#000000;font-family:arial;font-size:9.30pt">financially secure than larger, more established companies. They may depend on a more limited management group </span><span style="color:#000000;font-family:arial;font-size:9.30pt">than larger capitalized companies.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Index-Related Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The index provider may rely on various sources of information to assess the criteria of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">components of the Underlying Index, including information that may be based on assumptions and estimates. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Neither the Fund nor BlackRock can offer assurances that the index provider’s methodology or sources of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">information will provide an accurate assessment of included components. Errors in index data, index computations </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or the construction of the Underlying Index in accordance with its methodology may occur, and the index provider </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may not identify or correct them promptly or at all, which may have an adverse impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political </span><span style="color:#000000;font-family:arial;font-size:9.30pt">unrest or war) may impact the index provider or a third-party data provider and could cause the index provider to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">postpone a scheduled rebalance. This could cause the Underlying Index to vary from its normal or expected </span><span style="color:#000000;font-family:arial;font-size:9.30pt">composition.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Passive Investment Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Because BlackRock does not select individual companies in the index that the Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tracks, the Fund may hold securities of companies that present risks that an investment adviser researching </span><span style="color:#000000;font-family:arial;font-size:9.30pt">individual securities might seek to avoid.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Tracking Error Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is subject to the risk of “tracking error,” which is the divergence of the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance from that of the Underlying Index. Tracking error may occur due to a number of factors, including </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differences between the securities and other assets held in the Fund’s portfolio and those included in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index; differences in the timing and methodologies used to value securities and other assets; </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transaction costs and other expenses incurred by the Fund that the Underlying Index does not incur; the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">holding of uninvested cash; differences in the timing of the accrual or the valuation of dividends or interest received </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the Fund or distributions paid to Fund shareholders; tax gains or losses; differences between the amount and/or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">timing of withholding taxes on dividends reflected in the Underlying Index from the Fund’s obligation, if any, for </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes; the requirements for the Fund to maintain pass-through tax treatment; portfolio </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transactions carried out to minimize the distribution of capital gains to shareholders; changes to the Underlying </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index, such as during a rebalancing or reconstitution; and impacts to the Fund of complying with certain regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">requirements or limits. A fund that tracks an index composed of a large number of securities or other assets may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">experience greater tracking error than a fund that tracks a more narrow index. Tracking error risk may be heightened </span><span style="color:#000000;font-family:arial;font-size:9.30pt">during times of increased market volatility or other unusual market conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Equity Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Stock markets are volatile. The price of equity securities fluctuates based on changes in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">company’s financial condition and overall market and economic conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Market Risk and Selection Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Market risk is the risk that one or more markets in which the Fund invests will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">security or other asset may decline due to changes in general market conditions, economic trends or events that </span><span style="color:#000000;font-family:arial;font-size:9.30pt">are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investments. Selection risk is the risk that the securities selected by Fund management will underperform the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets, the relevant indices or the securities selected by other funds with similar investment objectives and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment strategies. This means you may lose money.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Operational and Technology Risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is directly and indirectly susceptible to operational and technology </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks, including those related to human errors, processing errors, communication errors, systems failures, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the Fund and its shareholders or may impair the Fund’s operations. While the Fund’s service providers are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">required to have appropriate operational, information security and cybersecurity risk management policies and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may cause the Fund’s investments in such issuers to lose value.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Representative Sampling Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Representative sampling is a method of indexing that involves investing in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sample of securities that collectively have a similar investment profile to the Underlying Index and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">resemble the Underlying Index in terms of risk factors and other key characteristics. The Fund may or may not hold </span><span style="color:#000000;font-family:arial;font-size:9.30pt">every security in the Underlying Index. When the Fund deviates from a full replication indexing strategy to utilize a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sampling strategy, the Fund is subject to an increased risk of tracking error, in that the securities </span><span style="color:#000000;font-family:arial;font-size:9.30pt">selected in the aggregate for the Fund may not have an investment profile similar to those of the Underlying Index.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Risk of Investing in the United States </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Certain changes in the U.S. economy, such as when the U.S. economy </span><span style="color:#000000;font-family:arial;font-size:9.30pt">weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has </span><span style="color:#000000;font-family:arial;font-size:9.30pt">exposure.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> Performance Information <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The information shows you how the Fund’s performance has varied year by year and provides some indication of the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks of investing in the Fund. The table compares the Fund’s performance to that of the Russell 3000</span><span style="color:#000000;font-family:arial;font-size:5pt;position:relative;top:-3.25pt">®</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Index and the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Russell 2000. The Russell 2000 is relevant to the Fund because it has characteristics similar to the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment strategy. To the extent that dividends and distributions have been paid by the Fund, the performance </span><span style="color:#000000;font-family:arial;font-size:9.30pt">information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all </span><span style="color:#000000;font-family:arial;font-size:9.30pt">such investments, past performance (before and after taxes) is not an indication of future results. The table includes </span><span style="color:#000000;font-family:arial;font-size:9.30pt">all applicable fees. If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance, including its current net asset value, can be obtained by visiting www.blackrock.com or can be obtained </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by phone at </span><span style="color:#000000;font-family:arial;font-size:9.30pt">(800) 882-0052</span><span style="color:#000000;font-family:arial;font-size:9.30pt">.</span></div> The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. As with all such investments, past performance (before and after taxes) is not an indication of future results. www.blackrock.com (800) 882-0052 Class K Shares ANNUAL TOTAL RETURNS Russell 2000 Small-Cap Index Fund As of 12/31 <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">During the ten-year period shown in the bar chart, the highest return for a quarter was 31.35% (quarter ended </span><span style="color:#000000;font-family:arial;font-size:9.30pt">December 31, 2020) and the lowest return for a quarter was -30.51% (quarter ended March 31, 2020).</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> highest return 0.3135 2020-12-31 lowest return -0.3051 2020-03-31 For the periods ended 12/31/25Average Annual Total Returns 0.1283 0.0611 0.0966 0.1180 0.0495 0.0855 0.0798 0.0450 0.0757 0.1715 0.1315 0.1429 0.1281 0.0609 0.0962 <div style="margin-top:12pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not </span><span style="color:#000000;font-family:arial;font-size:9.30pt">reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. Fund OverviewKey Facts About iShares MSCI EAFE International Index Fund Investment Objective <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The investment objective of iShares MSCI EAFE International Index Fund (“MSCI EAFE International Index Fund”or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“Fund”), a series of BlackRock Index Funds, Inc. (the “Corporation”), is to match the performance of the MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index (Europe, Australasia, Far East) (the “MSCI EAFE Index” or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">) in U.S. dollars with net </span><span style="color:#000000;font-family:arial;font-size:9.30pt">dividends as closely as possible before the deduction of Fund expenses.</span></div> Fees and Expenses of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This table describes the fees and expenses that you may pay if you buy, hold and sell Class K Shares of MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">International Index Fund. </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">You may pay other fees, such as brokerage commissions and other fees to your financial </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">professional or your selected securities dealer, broker, investment adviser, service provider or industry professional </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">(including BlackRock Advisors, LLC (</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">BlackRock</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">) and its affiliates) (each, a </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">Financial Intermediary</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">), which are </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">not reflected in the table and example below.</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0001 0 0.0003 0.0003 0.0004 0.0004 June 30, 2027 Example: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other </span><span style="color:#000000;font-family:arial;font-size:9.30pt">mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then </span><span style="color:#000000;font-family:arial;font-size:9.30pt">redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or lower, based on these assumptions your costs would be:</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> 4 13 23 51 Portfolio Turnover: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="color:#000000;font-family:arial;font-size:9.30pt">8</span><span style="color:#000000;font-family:arial;font-size:9.30pt">% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">of the average value of its portfolio.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> 0.08 Principal Investment Strategies of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund employs a “passive” management approach, attempting to invest in a portfolio of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">assets whose performance is expected to match approximately the performance of the MSCI EAFE Index. The Fund will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be substantially invested in securities in the MSCI EAFE Index, and will invest, under normal circumstances, at least </span><span style="color:#000000;font-family:arial;font-size:9.30pt">80% of its assets in securities or other financial instruments that are components of or have economic characteristics </span><span style="color:#000000;font-family:arial;font-size:9.30pt">similar to the securities included in the MSCI EAFE Index. The Fund may change its target index if Fund management </span><span style="color:#000000;font-family:arial;font-size:9.30pt">believes a different index would better enable the Fund to match the performance of the market segment represented </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the current index.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund invests in a statistically selected sample of equity securities included in the MSCI </span><span style="color:#000000;font-family:arial;font-size:9.30pt">EAFE Index and in derivative instruments linked to the MSCI EAFE Index. Equity securities include common stock, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">preferred stock and securities or other instruments whose price is linked to the value of common stock. The Fund will, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">under normal circumstances, invest in all of the countries represented in the MSCI EAFE Index. The Fund may not, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">however, invest in all of the companies within a country represented in the MSCI EAFE Index, or in the same weightings </span><span style="color:#000000;font-family:arial;font-size:9.30pt">as in the MSCI EAFE Index.</span></div> You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Equity Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Stock markets are volatile. The price of equity securities fluctuates based on changes in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">company’s financial condition and overall market and economic conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Foreign Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Foreign investments often involve special risks not present in U.S. investments that can </span><span style="color:#000000;font-family:arial;font-size:9.30pt">increase the chances that the Fund will lose money. These risks include:</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">oversight.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Changes in foreign currency exchange rates can affect the value of the Fund’s portfolio.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The economies of certain foreign markets may not compare favorably with the economy of the United States with </span><span style="color:#000000;font-family:arial;font-size:9.30pt">respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">payments position.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The governments of certain countries, or the U.S. Government with respect to certain countries, may prohibit or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer </span><span style="color:#000000;font-family:arial;font-size:9.30pt">currency, securities, derivatives or other assets.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the same extent as does the United States and may not have laws to protect investors that are comparable to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">U.S. securities laws.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">securities not typically associated with settlement and clearance of U.S. investments.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund’s claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div style="line-height:10.695pt;margin-left:24pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign country, accruals in the Fund’s net asset value for such refunds may be written down partially or in full, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">which will adversely affect the Fund’s net asset value.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Index-Related Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The index provider may rely on various sources of information to assess the criteria of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">components of the Underlying Index, including information that may be based on assumptions and estimates. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Neither the Fund nor BlackRock can offer assurances that the index provider’s methodology or sources of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">information will provide an accurate assessment of included components. Errors in index data, index computations </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or the construction of the Underlying Index in accordance with its methodology may occur, and the index provider </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may not identify or correct them promptly or at all, which may have an adverse impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political </span><span style="color:#000000;font-family:arial;font-size:9.30pt">unrest or war) may impact the index provider or a third-party data provider and could cause the index provider to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">postpone a scheduled rebalance. This could cause the Underlying Index to vary from its normal or expected </span><span style="color:#000000;font-family:arial;font-size:9.30pt">composition.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Large-Capitalization Companies Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> — Large-capitalization companies may be less able than smaller-capitalization </span><span style="color:#000000;font-family:arial;font-size:9.30pt">companies to adapt to changing market conditions and competitive challenges. Large-capitalization companies may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be more mature and subject to more limited growth potential compared with smaller-capitalization companies. The </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance of large-capitalization companies could trail the overall performance of the broader securities markets.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Passive Investment Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Because BlackRock does not select individual companies in the index that the Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tracks, the Fund may hold securities of companies that present risks that an investment adviser researching </span><span style="color:#000000;font-family:arial;font-size:9.30pt">individual securities might seek to avoid.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Small and Mid-Capitalization Company Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Companies with small or mid-size market capitalizations will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">normally have more limited product lines, markets and financial resources and will be dependent upon a more </span><span style="color:#000000;font-family:arial;font-size:9.30pt">limited management group than larger capitalized companies. In addition, it is more difficult to get information on </span><span style="color:#000000;font-family:arial;font-size:9.30pt">smaller companies, which tend to be less well known, have shorter operating histories, do not have significant </span><span style="color:#000000;font-family:arial;font-size:9.30pt">ownership by large investors and are followed by relatively few securities analysts.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Tracking Error Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is subject to the risk of “tracking error,” which is the divergence of the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance from that of the Underlying Index. Tracking error may occur due to a number of factors, including </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differences between the securities and other assets held in the Fund’s portfolio and those included in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index; differences in the timing and methodologies used to value securities and other assets; </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transaction costs and other expenses incurred by the Fund that the Underlying Index does not incur; the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">holding of uninvested cash; differences in the timing of the accrual or the valuation of dividends or interest received </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the Fund or distributions paid to Fund shareholders; tax gains or losses; differences between the amount and/or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">timing of withholding taxes on dividends reflected in the Underlying Index from the Fund’s obligation, if any, for </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes; the requirements for the Fund to maintain pass-through tax treatment; portfolio </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transactions carried out to minimize the distribution of capital gains to shareholders; changes to the Underlying </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index, such as during a rebalancing or reconstitution; and impacts to the Fund of complying with certain regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">requirements or limits. A fund that tracks an index composed of a large number of securities or other assets may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">experience greater tracking error than a fund that tracks a more narrow index. Tracking error risk may be heightened </span><span style="color:#000000;font-family:arial;font-size:9.30pt">during times of increased market volatility or other unusual market conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Market Risk and Selection Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Market risk is the risk that one or more markets in which the Fund invests will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">security or other asset may decline due to changes in general market conditions, economic trends or events that </span><span style="color:#000000;font-family:arial;font-size:9.30pt">are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investments. Selection risk is the risk that the securities selected by Fund management will underperform the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets, the relevant indices or the securities selected by other funds with similar investment objectives and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment strategies. This means you may lose money.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Operational and Technology Risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is directly and indirectly susceptible to operational and technology </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks, including those related to human errors, processing errors, communication errors, systems failures, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the Fund and its shareholders or may impair the Fund’s operations. While the Fund’s service providers are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">required to have appropriate operational, information security and cybersecurity risk management policies and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may cause the Fund’s investments in such issuers to lose value.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Representative Sampling Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Representative sampling is a method of indexing that involves investing in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sample of securities that collectively have a similar investment profile to the Underlying Index and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">resemble the Underlying Index in terms of risk factors and other key characteristics. The Fund may or may not hold </span><span style="color:#000000;font-family:arial;font-size:9.30pt">every security in the Underlying Index. When the Fund deviates from a full replication indexing strategy to utilize a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sampling strategy, the Fund is subject to an increased risk of tracking error, in that the securities </span><span style="color:#000000;font-family:arial;font-size:9.30pt">selected in the aggregate for the Fund may not have an investment profile similar to those of the Underlying Index.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> Performance Information <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The information shows you how the Fund’s performance has varied year by year and provides some indication of the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks of investing in the Fund. The table compares the Fund’s performance to that of the MSCI EAFE Index (Net). To the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance (before and after taxes) is not an indication of future results. The table includes all applicable fees. If the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these </span><span style="color:#000000;font-family:arial;font-size:9.30pt">periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance, including its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">current net asset value, can be obtained by visiting www.blackrock.com or can be obtained by phone at </span><span style="color:#000000;font-family:arial;font-size:9.30pt">(800) 882-0052</span><span style="color:#000000;font-family:arial;font-size:9.30pt">.</span></div> The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. As with all such investments, past performance (before and after taxes) is not an indication of future results. www.blackrock.com (800) 882-0052 Class K Shares ANNUAL TOTAL RETURNS MSCI EAFE International Index Fund As of 12/31 <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">During the ten-year period shown in the bar chart, the highest return for a quarter was 18.23% (quarter ended </span><span style="color:#000000;font-family:arial;font-size:9.30pt">December 31, 2022) and the lowest return for a quarter was -23.29% (quarter ended March 31, 2020).</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> highest return 0.1823 2022-12-31 lowest return -0.2329 2020-03-31 For the periods ended 12/31/25Average Annual Total Returns 0.3173 0.0912 0.0837 0.3033 0.0834 0.0768 0.1933 0.0711 0.0672 0.3122 0.0892 0.0818 <div style="margin-top:12pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not </span><span style="color:#000000;font-family:arial;font-size:9.30pt">reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. Fund OverviewKey Facts About iShares Russell 2000 Small-Cap Index Fund Investment Objective <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The investment objective of iShares Russell 2000 Small-Cap Index Fund (</span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Russell 2000 Small-Cap Index Fund</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Fund</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">), a series of BlackRock Index Funds, Inc. (the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Corporation</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">), is to match the performance of the Russell </span><span style="color:#000000;font-family:arial;font-size:9.30pt">2000</span><span style="color:#000000;font-family:arial;font-size:5pt;position:relative;top:-3.25pt">®</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Index (the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Russell 2000</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">) as closely as possible before the deduction of Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">expenses.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> Fees and Expenses of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This table describes the fees and expenses that you may pay if you buy, hold and sell Investor P Shares of the Fund. </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">You may pay other fees, such as brokerage commissions and other fees to your Financial Intermediary (as defined </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">below), which are not reflected in the table and example below. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">You may qualify for sales charge discounts if you and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">your family invest, or agree to invest in the future, at least $25,000 in the fund complex advised by BlackRock </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Advisors, LLC (“BlackRock”) or its affiliates. More information about these and other discounts is available from your </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Financial Intermediary and in the “Details About the Share Class” section on page 26 of the Fund’s prospectus and in </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the “Purchase of Shares” section on page II-90 of Part II of the Fund’s Statement of Additional Information (the “SAI”).</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the fund complex advised by BlackRock Advisors, LLC (“BlackRock”) or its affiliates. 25000 Shareholder Fees (fees paid directly from your investment) 0.0525 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0001 0.0025 0.0013 0.0004 0.0009 0.0039 -0.0002 0.0037 June 30, 2027 Example: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other </span><span style="color:#000000;font-family:arial;font-size:9.30pt">mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then </span><span style="color:#000000;font-family:arial;font-size:9.30pt">redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or lower, based on these assumptions your costs would be:</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> 561 642 730 990 Portfolio Turnover: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Series pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Example, affect the Fund’s performance. During the most recent fiscal year, the Series’ portfolio turnover rate was </span><span style="color:#000000;font-family:arial;font-size:9.30pt">21</span><span style="color:#000000;font-family:arial;font-size:9.30pt">% of the average value of its portfolio.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> 0.21 Principal Investment Strategies of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Russell 2000 Small-Cap Index Fund employs a “passive” management approach, attempting to invest in a portfolio of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">assets whose performance is expected to match approximately the performance of the Russell 2000. The Fund will be </span><span style="color:#000000;font-family:arial;font-size:9.30pt">substantially invested in securities in the Russell 2000, and will invest, under normal circumstances, at least 80% of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">its assets in securities or other financial instruments that are components of or have economic characteristics similar </span><span style="color:#000000;font-family:arial;font-size:9.30pt">to the securities included in the Russell 2000. The Fund may change its target index if Fund management believes a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">different index would better enable the Fund to match the performance of the market segment represented by the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">current index.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund may invest in a statistically selected sample of stocks included in the Russell 2000 and in derivative </span><span style="color:#000000;font-family:arial;font-size:9.30pt">instruments linked to the Russell 2000. The Fund may not invest in all of the common stocks in the Russell 2000, or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">in the same weightings as in the Russell 2000. The Fund chooses investments so that the market capitalizations, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">industry weightings and other fundamental characteristics of the stocks and derivative instruments chosen are similar </span><span style="color:#000000;font-family:arial;font-size:9.30pt">to the Russell 2000 as a whole. As of March 31, 2026, the companies in the Russell 2000 have a market </span><span style="color:#000000;font-family:arial;font-size:9.30pt">capitalization ranging from $3.29 million to $39.25 billion.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund is a “feeder” fund that invests all of its assets in the Series, a series of the Master LLC, which has the same </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment objective and strategies as the Fund. All investments are made at the Series level. This structure is </span><span style="color:#000000;font-family:arial;font-size:9.30pt">sometimes called a “master/feeder” structure. The Fund’s investment results will correspond directly to the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment results of the Series. For simplicity, this prospectus uses the name of the Fund or the term “Fund” (as </span><span style="color:#000000;font-family:arial;font-size:9.30pt">applicable) to include the Series.</span></div> You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Small Cap Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Small cap companies may have limited product lines or markets. They may be less </span><span style="color:#000000;font-family:arial;font-size:9.30pt">financially secure than larger, more established companies. They may depend on a more limited management group </span><span style="color:#000000;font-family:arial;font-size:9.30pt">than larger capitalized companies.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Index-Related Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The index provider may rely on various sources of information to assess the criteria of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">components of the Underlying Index, including information that may be based on assumptions and estimates. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Neither the Fund nor BlackRock can offer assurances that the index provider’s methodology or sources of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">information will provide an accurate assessment of included components. Errors in index data, index computations </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or the construction of the Underlying Index in accordance with its methodology may occur, and the index provider </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may not identify or correct them promptly or at all, which may have an adverse impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div style="line-height:10.695pt;margin-left:12pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">unrest or war) may impact the index provider or a third-party data provider and could cause the index provider to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">postpone a scheduled rebalance. This could cause the Underlying Index to vary from its normal or expected </span><span style="color:#000000;font-family:arial;font-size:9.30pt">composition.</span></div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Passive Investment Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Because BlackRock does not select individual companies in the index that the Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tracks, the Fund may hold securities of companies that present risks that an investment adviser researching </span><span style="color:#000000;font-family:arial;font-size:9.30pt">individual securities might seek to avoid.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Tracking Error Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is subject to the risk of “tracking error,” which is the divergence of the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance from that of the Underlying Index. Tracking error may occur due to a number of factors, including </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differences between the securities and other assets held in the Fund’s portfolio and those included in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index; differences in the timing and methodologies used to value securities and other assets; </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transaction costs and other expenses incurred by the Fund that the Underlying Index does not incur; the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">holding of uninvested cash; differences in the timing of the accrual or the valuation of dividends or interest received </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the Fund or distributions paid to Fund shareholders; tax gains or losses; differences between the amount and/or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">timing of withholding taxes on dividends reflected in the Underlying Index from the Fund’s obligation, if any, for </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes; the requirements for the Fund to maintain pass-through tax treatment; portfolio </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transactions carried out to minimize the distribution of capital gains to shareholders; changes to the Underlying </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index, such as during a rebalancing or reconstitution; and impacts to the Fund of complying with certain regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">requirements or limits. A fund that tracks an index composed of a large number of securities or other assets may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">experience greater tracking error than a fund that tracks a more narrow index. Tracking error risk may be heightened </span><span style="color:#000000;font-family:arial;font-size:9.30pt">during times of increased market volatility or other unusual market conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Equity Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Stock markets are volatile. The price of equity securities fluctuates based on changes in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">company’s financial condition and overall market and economic conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Market Risk and Selection Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Market risk is the risk that one or more markets in which the Fund invests will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">security or other asset may decline due to changes in general market conditions, economic trends or events that </span><span style="color:#000000;font-family:arial;font-size:9.30pt">are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investments. Selection risk is the risk that the securities selected by Fund management will underperform the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets, the relevant indices or the securities selected by other funds with similar investment objectives and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment strategies. This means you may lose money.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Operational and Technology Risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is directly and indirectly susceptible to operational and technology </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks, including those related to human errors, processing errors, communication errors, systems failures, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the Fund and its shareholders or may impair the Fund’s operations. While the Fund’s service providers are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">required to have appropriate operational, information security and cybersecurity risk management policies and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may cause the Fund’s investments in such issuers to lose value.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Representative Sampling Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Representative sampling is a method of indexing that involves investing in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sample of securities that collectively have a similar investment profile to the Underlying Index and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">resemble the Underlying Index in terms of risk factors and other key characteristics. The Fund may or may not hold </span><span style="color:#000000;font-family:arial;font-size:9.30pt">every security in the Underlying Index. When the Fund deviates from a full replication indexing strategy to utilize a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sampling strategy, the Fund is subject to an increased risk of tracking error, in that the securities </span><span style="color:#000000;font-family:arial;font-size:9.30pt">selected in the aggregate for the Fund may not have an investment profile similar to those of the Underlying Index.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Risk of Investing in the United States </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Certain changes in the U.S. economy, such as when the U.S. economy </span><span style="color:#000000;font-family:arial;font-size:9.30pt">weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has </span><span style="color:#000000;font-family:arial;font-size:9.30pt">exposure.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> Performance Information <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The information shows you how the Fund’s performance has varied year by year and provides some indication of the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks of investing in the Fund. Investor P Shares commenced operations on August 6, 2018. As a result, the returns </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shown below for Investor P Shares prior to August 6, 2018 are based on the Fund’s Institutional Shares, which are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">offered in a separate prospectus, adjusted to reflect the fees and expenses applicable to Investor P Shares and, in </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the case of the table, the front-end sales charge applicable to Investor P Shares.</span></div><div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The table compares the Fund’s performance to that of the Russell 3000</span><span style="color:#000000;font-family:arial;font-size:5pt;position:relative;top:-3.25pt">®</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Index and the Russell 2000. The Russell </span><span style="color:#000000;font-family:arial;font-size:9.30pt">2000 is relevant to the Fund because it has characteristics similar to the Fund’s investment strategy. To the extent </span><span style="color:#000000;font-family:arial;font-size:9.30pt">that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">table assumes reinvestment of the dividends and distributions. As with all such investments, past performance </span><span style="color:#000000;font-family:arial;font-size:9.30pt">(before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they </span><span style="color:#000000;font-family:arial;font-size:9.30pt">were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. If </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these </span><span style="color:#000000;font-family:arial;font-size:9.30pt">periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance, including its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">current net asset value, can be obtained by visiting www.blackrock.com or can be obtained by phone at </span><span style="color:#000000;font-family:arial;font-size:9.30pt">(800) 882-0052</span><span style="color:#000000;font-family:arial;font-size:9.30pt">.</span></div> The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. As with all such investments, past performance (before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. www.blackrock.com (800) 882-0052 Investor P Shares ANNUAL TOTAL RETURNS Russell 2000 Small-Cap Index Fund As of 12/31 <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">During the ten-year period shown in the bar chart, the highest return for a quarter was 31.23% (quarter ended </span><span style="color:#000000;font-family:arial;font-size:9.30pt">December 31, 2020) and the lowest return for a quarter was -30.59% (quarter ended March 31, 2020).</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> highest return 0.3123 2020-12-31 lowest return -0.3059 2020-03-31 For the periods ended 12/31/25Average Annual Total Returns 0.0656 0.0465 0.0873 0.0569 0.0360 0.0770 0.0423 0.0337 0.0680 0.1715 0.1315 0.1429 0.1281 0.0609 0.0962 <div style="margin-top:12pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not </span><span style="color:#000000;font-family:arial;font-size:9.30pt">reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. Fund Overview Key Facts About iShares MSCI EAFE International Index Fund Investment Objective <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The investment objective of iShares MSCI EAFE International Index Fund (</span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Fund</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">), a series of BlackRock Index Funds, Inc. (the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Corporation</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">), is to match the performance of the MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index (Europe, Australasia, Far East) (the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE Index</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">) in U.S. dollars with net </span><span style="color:#000000;font-family:arial;font-size:9.30pt">dividends as closely as possible before the deduction of Fund expenses.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> Fees and Expenses of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This table describes the fees and expenses that you may pay if you buy, hold and sell Investor P Shares of MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">International Index Fund. </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">You may pay other fees, such as brokerage commissions and other fees to your Financial </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">Intermediary (as defined below), which are not reflected in the table and example below. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">You may qualify for sales </span><span style="color:#000000;font-family:arial;font-size:9.30pt">charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the fund complex </span><span style="color:#000000;font-family:arial;font-size:9.30pt">advised by BlackRock Advisors, LLC (“BlackRock”) or its affiliates. More information about these and other discounts </span><span style="color:#000000;font-family:arial;font-size:9.30pt">is available from your Financial Intermediary and in the “Details About the Share Class” section on page 27 of the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Fund’s prospectus and in the “Purchase of Shares” section on page II-98 of Part II of the Fund’s Statement of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Additional Information (the “SAI”).</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the fund complex advised by BlackRock Advisors, LLC (“BlackRock”) or its affiliates. 25000 Shareholder Fees (fees paid directly from your investment) 0.0525 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0001 0.0025 0.0008 0.0008 0.0034 0.0034 June 30, 2027 Example: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other </span><span style="color:#000000;font-family:arial;font-size:9.30pt">mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then </span><span style="color:#000000;font-family:arial;font-size:9.30pt">redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% </span></div><div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or lower, based on these assumptions your costs would be:</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> 558 629 706 933 Portfolio Turnover: <div style="line-height:10.695pt;margin-top:0.0pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="color:#000000;font-family:arial;font-size:9.30pt">8</span><span style="color:#000000;font-family:arial;font-size:9.30pt">% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">of the average value of its portfolio.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> 0.08 Principal Investment Strategies of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund employs a “passive” management approach, attempting to invest in a portfolio of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">assets whose performance is expected to match approximately the performance of the MSCI EAFE Index. The Fund will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be substantially invested in securities in the MSCI EAFE Index, and will invest, under normal circumstances, at least </span><span style="color:#000000;font-family:arial;font-size:9.30pt">80% of its assets in securities or other financial instruments that are components of or have economic characteristics </span><span style="color:#000000;font-family:arial;font-size:9.30pt">similar to the securities included in the MSCI EAFE Index. The Fund may change its target index if Fund management </span><span style="color:#000000;font-family:arial;font-size:9.30pt">believes a different index would better enable the Fund to match the performance of the market segment represented </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the current index.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund invests in a statistically selected sample of equity securities included in the MSCI </span><span style="color:#000000;font-family:arial;font-size:9.30pt">EAFE Index and in derivative instruments linked to the MSCI EAFE Index. Equity securities include common stock, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">preferred stock and securities or other instruments whose price is linked to the value of common stock. The Fund will, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">under normal circumstances, invest in all of the countries represented in the MSCI EAFE Index. The Fund may not, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">however, invest in all of the companies within a country represented in the MSCI EAFE Index, or in the same weightings </span><span style="color:#000000;font-family:arial;font-size:9.30pt">as in the MSCI EAFE Index.</span></div> You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Equity Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Stock markets are volatile. The price of equity securities fluctuates based on changes in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">company’s financial condition and overall market and economic conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Foreign Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Foreign investments often involve special risks not present in U.S. investments that can </span><span style="color:#000000;font-family:arial;font-size:9.30pt">increase the chances that the Fund will lose money. These risks include:</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">oversight.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Changes in foreign currency exchange rates can affect the value of the Fund’s portfolio.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The economies of certain foreign markets may not compare favorably with the economy of the United States with </span><span style="color:#000000;font-family:arial;font-size:9.30pt">respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">payments position.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The governments of certain countries, or the U.S. Government with respect to certain countries, may prohibit or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer </span><span style="color:#000000;font-family:arial;font-size:9.30pt">currency, securities, derivatives or other assets.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the same extent as does the United States and may not have laws to protect investors that are comparable to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">U.S. securities laws.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">securities not typically associated with settlement and clearance of U.S. investments.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund’s claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign country, accruals in the Fund’s net asset value for such refunds may be written down partially or in full, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">which will adversely affect the Fund’s net asset value.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Index-Related Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The index provider may rely on various sources of information to assess the criteria of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">components of the Underlying Index, including information that may be based on assumptions and estimates. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Neither the Fund nor BlackRock can offer assurances that the index provider’s methodology or sources of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">information will provide an accurate assessment of included components. Errors in index data, index computations </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or the construction of the Underlying Index in accordance with its methodology may occur, and the index provider </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may not identify or correct them promptly or at all, which may have an adverse impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political </span><span style="color:#000000;font-family:arial;font-size:9.30pt">unrest or war) may impact the index provider or a third-party data provider and could cause the index provider to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">postpone a scheduled rebalance. This could cause the Underlying Index to vary from its normal or expected </span><span style="color:#000000;font-family:arial;font-size:9.30pt">composition.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Large-Capitalization Companies Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> — Large-capitalization companies may be less able than smaller-capitalization </span><span style="color:#000000;font-family:arial;font-size:9.30pt">companies to adapt to changing market conditions and competitive challenges. Large-capitalization companies may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be more mature and subject to more limited growth potential compared with smaller-capitalization companies. The </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance of large-capitalization companies could trail the overall performance of the broader securities markets.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Passive Investment Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Because BlackRock does not select individual companies in the index that the Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tracks, the Fund may hold securities of companies that present risks that an investment adviser researching </span><span style="color:#000000;font-family:arial;font-size:9.30pt">individual securities might seek to avoid.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Small and Mid-Capitalization Company Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Companies with small or mid-size market capitalizations will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">normally have more limited product lines, markets and financial resources and will be dependent upon a more </span><span style="color:#000000;font-family:arial;font-size:9.30pt">limited management group than larger capitalized companies. In addition, it is more difficult to get information on </span><span style="color:#000000;font-family:arial;font-size:9.30pt">smaller companies, which tend to be less well known, have shorter operating histories, do not have significant </span><span style="color:#000000;font-family:arial;font-size:9.30pt">ownership by large investors and are followed by relatively few securities analysts.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Tracking Error Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is subject to the risk of “tracking error,” which is the divergence of the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance from that of the Underlying Index. Tracking error may occur due to a number of factors, including </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differences between the securities and other assets held in the Fund’s portfolio and those included in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index; differences in the timing and methodologies used to value securities and other assets; </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transaction costs and other expenses incurred by the Fund that the Underlying Index does not incur; the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">holding of uninvested cash; differences in the timing of the accrual or the valuation of dividends or interest received </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the Fund or distributions paid to Fund shareholders; tax gains or losses; differences between the amount and/or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">timing of withholding taxes on dividends reflected in the Underlying Index from the Fund’s obligation, if any, for </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes; the requirements for the Fund to maintain pass-through tax treatment; portfolio </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transactions carried out to minimize the distribution of capital gains to shareholders; changes to the Underlying </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index, such as during a rebalancing or reconstitution; and impacts to the Fund of complying with certain regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">requirements or limits. A fund that tracks an index composed of a large number of securities or other assets may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">experience greater tracking error than a fund that tracks a more narrow index. Tracking error risk may be heightened </span><span style="color:#000000;font-family:arial;font-size:9.30pt">during times of increased market volatility or other unusual market conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Market Risk and Selection Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Market risk is the risk that one or more markets in which the Fund invests will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">security or other asset may decline due to changes in general market conditions, economic trends or events that </span><span style="color:#000000;font-family:arial;font-size:9.30pt">are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investments. Selection risk is the risk that the securities selected by Fund management will underperform the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets, the relevant indices or the securities selected by other funds with similar investment objectives and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment strategies. This means you may lose money.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Operational and Technology Risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is directly and indirectly susceptible to operational and technology </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks, including those related to human errors, processing errors, communication errors, systems failures, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the Fund and its shareholders or may impair the Fund’s operations. While the Fund’s service providers are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">required to have appropriate operational, information security and cybersecurity risk management policies and </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div style="line-height:10.695pt;margin-left:12pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may cause the Fund’s investments in such issuers to lose value.</span></div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Representative Sampling Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Representative sampling is a method of indexing that involves investing in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sample of securities that collectively have a similar investment profile to the Underlying Index and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">resemble the Underlying Index in terms of risk factors and other key characteristics. The Fund may or may not hold </span><span style="color:#000000;font-family:arial;font-size:9.30pt">every security in the Underlying Index. When the Fund deviates from a full replication indexing strategy to utilize a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sampling strategy, the Fund is subject to an increased risk of tracking error, in that the securities </span><span style="color:#000000;font-family:arial;font-size:9.30pt">selected in the aggregate for the Fund may not have an investment profile similar to those of the Underlying Index.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> Performance Information <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The information shows you how the Fund’s performance has varied year by year and provides some indication of the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks of investing in the Fund. Investor P Shares commenced operations on August 6, 2018. As a result, the returns </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shown below for Investor P Shares prior to August 6, 2018 are based on the Fund’s Institutional Shares, which are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">offered in a separate prospectus, adjusted to reflect the fees and expenses applicable to Investor P Shares and, in </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the case of the table, the front-end sales charge applicable to Investor P Shares.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The table compares the Fund’s performance to that of the MSCI EAFE Index (Net). To the extent that dividends and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes </span><span style="color:#000000;font-family:arial;font-size:9.30pt">reinvestment of the dividends and distributions. As with all such investments, past performance (before and after </span><span style="color:#000000;font-family:arial;font-size:9.30pt">taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns </span><span style="color:#000000;font-family:arial;font-size:9.30pt">would be less than those shown. However, the table includes all applicable fees and sales charge. If the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Fund’s returns would have been lower. Updated information on the Fund’s performance, including its current net asset </span><span style="color:#000000;font-family:arial;font-size:9.30pt">value, can be obtained by visiting www.blackrock.com or can be obtained by phone at </span><span style="color:#000000;font-family:arial;font-size:9.30pt">(800) 882-0052</span><span style="color:#000000;font-family:arial;font-size:9.30pt">.</span></div> The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. As with all such investments, past performance (before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charge. www.blackrock.com (800) 882-0052 Investor P Shares ANNUAL TOTAL RETURNS MSCI EAFE International Index Fund As of 12/31 <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">During the ten-year period shown in the bar chart, the highest return for a quarter was 18.11% (quarter ended </span><span style="color:#000000;font-family:arial;font-size:9.30pt">December 31, 2022) and the lowest return for a quarter was -23.38% (quarter ended March 31, 2020).</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> highest return 0.1811 2022-12-31 lowest return -0.2338 2020-03-31 For the periods ended 12/31/25Average Annual Total Returns 0.2441 0.0762 0.0746 0.2316 0.0692 0.0683 0.1493 0.0591 0.0597 0.3122 0.0892 0.0818 <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not </span><span style="color:#000000;font-family:arial;font-size:9.30pt">reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. Fund Overview Key Facts About iShares MSCI EAFE International Index Fund Investment Objective <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The investment objective of iShares MSCI EAFE International Index Fund (</span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Fund</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">), a series of BlackRock Index Funds, Inc. (the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Corporation</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">), is to match the performance of the MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index (Europe, Australasia, Far East) (the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE Index</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> or the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">“</span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index</span><span style="color:#000000;font-family:arial;font-size:9.30pt">”</span><span style="color:#000000;font-family:arial;font-size:9.30pt">) in U.S. dollars with net </span><span style="color:#000000;font-family:arial;font-size:9.30pt">dividends as closely as possible before the deduction of Fund expenses.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> Fees and Expenses of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This table describes the fees and expenses that you may pay if you buy, hold and sell Class G Shares of MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">International Index Fund. </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">You may pay other fees, such as brokerage commissions and other fees to your financial </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">professional or your selected securities dealer, broker, investment adviser, service provider or industry professional </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">(including BlackRock Advisors, LLC (“BlackRock”) and its affiliates) (each, a “Financial Intermediary”), which are </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-weight:bold">not reflected in the table and example below</span><span style="color:#000000;font-family:arial;font-size:9.30pt">.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0001 0 0.0002 0.0002 0.0003 0.0003 June 30, 2027 Example: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other </span><span style="color:#000000;font-family:arial;font-size:9.30pt">mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then </span><span style="color:#000000;font-family:arial;font-size:9.30pt">redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or lower, based on these assumptions your costs would be:</span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> 3 10 17 39 Portfolio Turnover: <div style="line-height:10.695pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="color:#000000;font-family:arial;font-size:9.30pt">8</span><span style="color:#000000;font-family:arial;font-size:9.30pt">% </span><span style="color:#000000;font-family:arial;font-size:9.30pt">of the average value of its portfolio.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> 0.08 Principal Investment Strategies of the Fund <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund employs a “passive” management approach, attempting to invest in a portfolio of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">assets whose performance is expected to match approximately the performance of the MSCI EAFE Index. The Fund will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be substantially invested in securities in the MSCI EAFE Index, and will invest, under normal circumstances, at least </span><span style="color:#000000;font-family:arial;font-size:9.30pt">80% of its assets in securities or other financial instruments that are components of or have economic characteristics </span><span style="color:#000000;font-family:arial;font-size:9.30pt">similar to the securities included in the MSCI EAFE Index. The Fund may change its target index if Fund management </span><span style="color:#000000;font-family:arial;font-size:9.30pt">believes a different index would better enable the Fund to match the performance of the market segment represented </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the current index.</span></div><div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">MSCI EAFE International Index Fund invests in a statistically selected sample of equity securities included in the MSCI </span><span style="color:#000000;font-family:arial;font-size:9.30pt">EAFE Index and in derivative instruments linked to the MSCI EAFE Index. Equity securities include common stock, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">preferred stock and securities or other instruments whose price is linked to the value of common stock. The Fund will, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">under normal circumstances, invest in all of the countries represented in the MSCI EAFE Index. The Fund may not, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">however, invest in all of the companies within a country represented in the MSCI EAFE Index, or in the same weightings </span><span style="color:#000000;font-family:arial;font-size:9.30pt">as in the MSCI EAFE Index.</span></div> You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Equity Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Stock markets are volatile. The price of equity securities fluctuates based on changes in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">company’s financial condition and overall market and economic conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Foreign Securities Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Foreign investments often involve special risks not present in U.S. investments that can </span><span style="color:#000000;font-family:arial;font-size:9.30pt">increase the chances that the Fund will lose money. These risks include:</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">oversight.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Changes in foreign currency exchange rates can affect the value of the Fund’s portfolio.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The economies of certain foreign markets may not compare favorably with the economy of the United States with </span><span style="color:#000000;font-family:arial;font-size:9.30pt">respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">payments position.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The governments of certain countries, or the U.S. Government with respect to certain countries, may prohibit or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer </span><span style="color:#000000;font-family:arial;font-size:9.30pt">currency, securities, derivatives or other assets.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the same extent as does the United States and may not have laws to protect investors that are comparable to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">U.S. securities laws.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">securities not typically associated with settlement and clearance of U.S. investments.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;margin-left:12pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:493.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The Fund’s claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the </span></div> </div> <div style="clear:both;position:relative;"> </div> </div><div style="line-height:10.695pt;margin-left:24pt;text-align:left;"><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign country, accruals in the Fund’s net asset value for such refunds may be written down partially or in full, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">which will adversely affect the Fund’s net asset value.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Index-Related Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The index provider may rely on various sources of information to assess the criteria of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">components of the Underlying Index, including information that may be based on assumptions and estimates. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Neither the Fund nor BlackRock can offer assurances that the index provider’s methodology or sources of </span><span style="color:#000000;font-family:arial;font-size:9.30pt">information will provide an accurate assessment of included components. Errors in index data, index computations </span><span style="color:#000000;font-family:arial;font-size:9.30pt">or the construction of the Underlying Index in accordance with its methodology may occur, and the index provider </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may not identify or correct them promptly or at all, which may have an adverse impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political </span><span style="color:#000000;font-family:arial;font-size:9.30pt">unrest or war) may impact the index provider or a third-party data provider and could cause the index provider to </span><span style="color:#000000;font-family:arial;font-size:9.30pt">postpone a scheduled rebalance. This could cause the Underlying Index to vary from its normal or expected </span><span style="color:#000000;font-family:arial;font-size:9.30pt">composition.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Large-Capitalization Companies Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> — Large-capitalization companies may be less able than smaller-capitalization </span><span style="color:#000000;font-family:arial;font-size:9.30pt">companies to adapt to changing market conditions and competitive challenges. Large-capitalization companies may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">be more mature and subject to more limited growth potential compared with smaller-capitalization companies. The </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance of large-capitalization companies could trail the overall performance of the broader securities markets.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Passive Investment Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Because BlackRock does not select individual companies in the index that the Fund </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tracks, the Fund may hold securities of companies that present risks that an investment adviser researching </span><span style="color:#000000;font-family:arial;font-size:9.30pt">individual securities might seek to avoid.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Small and Mid-Capitalization Company Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Companies with small or mid-size market capitalizations will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">normally have more limited product lines, markets and financial resources and will be dependent upon a more </span><span style="color:#000000;font-family:arial;font-size:9.30pt">limited management group than larger capitalized companies. In addition, it is more difficult to get information on </span><span style="color:#000000;font-family:arial;font-size:9.30pt">smaller companies, which tend to be less well known, have shorter operating histories, do not have significant </span><span style="color:#000000;font-family:arial;font-size:9.30pt">ownership by large investors and are followed by relatively few securities analysts.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Tracking Error Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is subject to the risk of “tracking error,” which is the divergence of the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">performance from that of the Underlying Index. Tracking error may occur due to a number of factors, including </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differences between the securities and other assets held in the Fund’s portfolio and those included in the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Underlying Index; differences in the timing and methodologies used to value securities and other assets; </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transaction costs and other expenses incurred by the Fund that the Underlying Index does not incur; the Fund’s </span><span style="color:#000000;font-family:arial;font-size:9.30pt">holding of uninvested cash; differences in the timing of the accrual or the valuation of dividends or interest received </span><span style="color:#000000;font-family:arial;font-size:9.30pt">by the Fund or distributions paid to Fund shareholders; tax gains or losses; differences between the amount and/or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">timing of withholding taxes on dividends reflected in the Underlying Index from the Fund’s obligation, if any, for </span><span style="color:#000000;font-family:arial;font-size:9.30pt">foreign withholding taxes; the requirements for the Fund to maintain pass-through tax treatment; portfolio </span><span style="color:#000000;font-family:arial;font-size:9.30pt">transactions carried out to minimize the distribution of capital gains to shareholders; changes to the Underlying </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index, such as during a rebalancing or reconstitution; and impacts to the Fund of complying with certain regulatory </span><span style="color:#000000;font-family:arial;font-size:9.30pt">requirements or limits. A fund that tracks an index composed of a large number of securities or other assets may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">experience greater tracking error than a fund that tracks a more narrow index. Tracking error risk may be heightened </span><span style="color:#000000;font-family:arial;font-size:9.30pt">during times of increased market volatility or other unusual market conditions.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Market Risk and Selection Risk </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— Market risk is the risk that one or more markets in which the Fund invests will </span><span style="color:#000000;font-family:arial;font-size:9.30pt">go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">security or other asset may decline due to changes in general market conditions, economic trends or events that </span><span style="color:#000000;font-family:arial;font-size:9.30pt">are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health </span><span style="color:#000000;font-family:arial;font-size:9.30pt">issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investments. Selection risk is the risk that the securities selected by Fund management will underperform the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">markets, the relevant indices or the securities selected by other funds with similar investment objectives and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">investment strategies. This means you may lose money.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;margin-top:4.805pt;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.00pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Operational and Technology Risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">— The Fund is directly and indirectly susceptible to operational and technology </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks, including those related to human errors, processing errors, communication errors, systems failures, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the Fund and its shareholders or may impair the Fund’s operations. While the Fund’s service providers are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">required to have appropriate operational, information security and cybersecurity risk management policies and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">procedures, their methods of risk management may differ from those of the Fund. Operational and technology risks </span><span style="color:#000000;font-family:arial;font-size:9.30pt">for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">may cause the Fund’s investments in such issuers to lose value.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> <div> <div style="clear:both;position:relative;width:100%;"> <div style="float:left;line-height:9.87pt;text-align:left;width:8pt;"><span style="color:#000000;font-family:arial;font-size:8.37pt;position:relative;top:-0.5pt">◼</span></div> <div style="float:left;line-height:10.80pt;margin-left:4pt;text-align:left;width:505.0pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic;font-weight:bold">Representative Sampling Risk</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:9.30pt;font-style:italic">—</span><span style="color:#000000;font-family:arial;font-size:9.30pt"> Representative sampling is a method of indexing that involves investing in a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sample of securities that collectively have a similar investment profile to the Underlying Index and </span><span style="color:#000000;font-family:arial;font-size:9.30pt">resemble the Underlying Index in terms of risk factors and other key characteristics. The Fund may or may not hold </span><span style="color:#000000;font-family:arial;font-size:9.30pt">every security in the Underlying Index. When the Fund deviates from a full replication indexing strategy to utilize a </span><span style="color:#000000;font-family:arial;font-size:9.30pt">representative sampling strategy, the Fund is subject to an increased risk of tracking error, in that the securities </span><span style="color:#000000;font-family:arial;font-size:9.30pt">selected in the aggregate for the Fund may not have an investment profile similar to those of the Underlying Index.</span></div> </div> <div style="clear:both;position:relative;"> </div> </div> Performance Information <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">The information shows you how the Fund’s performance has varied year by year and provides some indication of the </span><span style="color:#000000;font-family:arial;font-size:9.30pt">risks of investing in the Fund. Class G Shares commenced operations on October 16, 2023. As a result, the returns </span><span style="color:#000000;font-family:arial;font-size:9.30pt">shown below for Class G Shares prior to October 16, 2023 are based on the Fund’s Institutional Shares, which are </span><span style="color:#000000;font-family:arial;font-size:9.30pt">offered in a separate prospectus. The performance of Class G Shares would be substantially similar to Institutional </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Shares because Class G Shares and Institutional Shares invest in the same portfolio of securities and performance </span><span style="color:#000000;font-family:arial;font-size:9.30pt">would only differ to the extent that Class G Shares and Institutional Shares have different expenses. The actual </span><span style="color:#000000;font-family:arial;font-size:9.30pt">returns of Class G Shares would have been higher than those of the Institutional Shares because Class G Shares have </span><span style="color:#000000;font-family:arial;font-size:9.30pt">lower expenses than the Institutional Shares. The table compares the Fund’s performance to that of the MSCI EAFE </span><span style="color:#000000;font-family:arial;font-size:9.30pt">Index (Net). To the extent that dividends and distributions have been paid by the Fund, the performance information for </span><span style="color:#000000;font-family:arial;font-size:9.30pt">the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, </span><span style="color:#000000;font-family:arial;font-size:9.30pt">past performance (before and after taxes) is not an indication of future results. The table includes all applicable fees. </span><span style="color:#000000;font-family:arial;font-size:9.30pt">If the Fund’s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these </span><span style="color:#000000;font-family:arial;font-size:9.30pt">periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance, including its </span><span style="color:#000000;font-family:arial;font-size:9.30pt">current net asset value, can be obtained by visiting www.blackrock.com or can be obtained by phone at </span><span style="color:#000000;font-family:arial;font-size:9.30pt">(800) 882-0052</span><span style="color:#000000;font-family:arial;font-size:9.30pt">.</span></div> The information shows you how the Fund’s performance has varied year by year and provides some indication of the risks of investing in the Fund. As with all such investments, past performance (before and after taxes) is not an indication of future results. www.blackrock.com (800) 882-0052 Class G Shares ANNUAL TOTAL RETURNS MSCI EAFE International Index Fund As of 12/31 <div style="margin-top:6pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">During the ten-year period shown in the bar chart, the highest return for a quarter was 18.11% (quarter ended </span><span style="color:#000000;font-family:arial;font-size:9.30pt">December 31, 2022) and the lowest return for a quarter was -23.31% (quarter ended March 31, 2020).</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span><span style="color:#000000;font-family:arial;font-size:1pt;line-height:0.93pt"> </span></div> highest return 0.1811 2022-12-31 lowest return -0.2331 2020-03-31 For the periods ended 12/31/25Average Annual Total Returns 0.3176 0.0909 0.0834 0.3036 0.0831 0.0765 0.1935 0.0708 0.0669 0.3122 0.0892 0.0818 <div style="margin-top:12pt;"><span style="color:#000000;font-family:arial;font-size:9.30pt">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not </span><span style="color:#000000;font-family:arial;font-size:9.30pt">reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may </span><span style="color:#000000;font-family:arial;font-size:9.30pt">differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through </span><span style="color:#000000;font-family:arial;font-size:9.30pt">tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.</span><span style="color:#000000;font-family:arial;font-size:9.30pt;line-height:10.695pt"> </span></div> After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. The fees and expenses shown in the table and the example that follows include both the expenses of Russell 2000 Small-Cap Index Fund and Russell 2000 Small-Cap Index Fund’s share of the allocated expenses of Master Small Cap Index Series (the “Series”), a series of Quantitative Master Series LLC (the “Master LLC”). The management fees are paid by the Series. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 42, BlackRock has contractually agreed to waive the management fee with respect to any portion of the Series’ assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through June 30, 2027. In addition, BlackRock has contractually agreed to waive its management fees by the amount of investment advisory fees the Series pays to BlackRock indirectly through its investment in money market funds managed by BlackRock or its affiliates, through June 30, 2027. The contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Master LLC or by a vote of a majority of the outstanding voting securities of the Series. The Total Annual Fund Operating Expenses and Miscellaneous Other Expenses do not correlate to the ratios of expenses to average net assets given in the Fund’s most recent Annual Financial Statements and Additional Information report, which do not include Acquired Fund Fees and Expenses. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 36, BlackRock has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through June 30, 2027. In addition, BlackRock has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to BlackRock indirectly through its investment in money market funds managed by BlackRock or its affiliates, through June 30, 2027. The contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or by a vote of a majority of the outstanding voting securities of the Fund. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 36, BlackRock has contractually agreed to waive the management fee with respect to any portion of the Series’ assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through June 30, 2027. In addition, BlackRock has contractually agreed to waive its management fees by the amount of investment advisory fees the Series pays to BlackRock indirectly through its investment in money market funds managed by BlackRock or its affiliates, through June 30, 2027. The contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Master LLC or by a vote of a majority of the outstanding voting securities of the Series. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 36, BlackRock has contractually agreed to waive and/or reimburse fees and/or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements of Russell 2000 Small-Cap Index Fund (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) to 0.07% (for Class K Shares) of average daily net assets through June 30, 2027. In addition to the contractual waiver with respect to the Fund, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements of the Series (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Series expenses) to 0.07% of average daily net assets through June 30, 2027. These contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or of the Master LLC, as applicable, or by a vote of a majority of the outstanding voting securities of the Fund or the Series, as applicable. Independent Expenses consist of the Fund’s allocable portion of the fees and expenses of the independent directors of the Corporation, counsel to such independent directors and the independent registered public accounting firm that provides audit services to the Fund. BlackRock has contractually agreed to reimburse, or provide offsetting credits to, the Fund for Independent Expenses through June 30, 2036. After giving effect to such contractual arrangements, Independent Expenses will be 0.00%. Such contractual arrangements may not be terminated prior to July 1, 2036 without the consent a majority of the non-interested directors of the Corporation (with 90 days’ notice) or by a vote of the majority of outstanding voting securities of the Fund. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 42, BlackRock has contractually agreed to waive and/or reimburse fees and/or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements of Russell 2000 Small-Cap Index Fund (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) to 0.37% (for Investor A Shares) and 0.12% (for Institutional Shares) of average daily net assets through June 30, 2027. In addition to the contractual waiver with respect to the Fund, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements of the Series (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Series expenses) to 0.07% of average daily net assets through June 30, 2027. These contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or of the Master LLC, as applicable, or by a vote of a majority of the outstanding voting securities of the Fund or the Series, as applicable. Returns for net indices generally assume the reinvestment of dividends after the deduction of the maximum withholding tax in each country applicable to non-residents of the country as determined by the index provider. Such indices use withholding tax rates that are often at a higher rate than the rates to which the Fund is subject in each country, including for countries where the Fund is not subject to withholding taxes. When this is the case, index performance will be lower than if the index used the Fund’s applicable withholding tax rates, if any. The fees and expenses shown in the table and the example that follows include both the expenses of Russell 2000 Small-Cap Index Fund and Russell 2000 Small-Cap Index Fund’s share of the allocated expenses of Master Small Cap Index Series (the “Series”), a series of Quantitative Master Series LLC (the “Master LLC”). The management fees are paid by the Series. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 38, BlackRock has contractually agreed to waive the management fee with respect to any portion of the Series’ assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through June 30, 2027. In addition, BlackRock has contractually agreed to waive its management fees by the amount of investment advisory fees the Series pays to BlackRock indirectly through its investment in money market funds managed by BlackRock or its affiliates, through June 30, 2027. The contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Master LLC or by a vote of a majority of the outstanding voting securities of the Series. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 38, BlackRock has contractually agreed to waive and/or reimburse fees and/or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements of Russell 2000 Small-Cap Index Fund (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) to 0.37% for Investor P Shares of average daily net assets through June 30, 2027. In addition to the contractual waiver with respect to the Fund, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements of the Series (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Series expenses) to 0.07% of average daily net assets through June 30, 2027. These contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or of the Master LLC, as applicable, or by a vote of a majority of the outstanding voting securities of the Fund or the Series, as applicable. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 38, BlackRock has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through June 30, 2027. In addition, BlackRock has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to BlackRock indirectly through its investment in money market funds managed by BlackRock or its affiliates, through June 30, 2027. The contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or by a vote of a majority of the outstanding voting securities of the Fund. Independent Expenses consist of the Fund’s allocable portion of the fees and expenses of the independent directors of the Corporation, counsel to such independent directors and the independent registered public accounting firm that provides audit services to the Fund. BlackRock has contractually agreed to reimburse, or provide offsetting credits to, the Fund for Independent Expenses through June 30, 2036. After giving effect to such contractual arrangements, Independent Expenses will be 0.00%. Such contractual arrangements may not be terminated prior to July 1, 2036 without the consent a majority of the non-interested directors of the Corporation (with 90 days’ notice) or by a vote of the majority of outstanding voting securities of the Fund. Returns for net indices generally assume the reinvestment of dividends after the deduction of the maximum withholding tax in each country applicable to non-residents of the country as determined by the index provider. Such indices use withholding tax rates that are often at a higher rate than the rates to which the Fund is subject in each country, including for countries where the Fund is not subject to withholding taxes. When this is the case, index performance will be lower than if the index used the Fund’s applicable withholding tax rates, if any. As described in the “Management of the Fund” section of the Fund’s prospectus beginning on page 26, BlackRock has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through June 30, 2027. In addition, BlackRock has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to BlackRock indirectly through its investment in money market funds managed by BlackRock or its affiliates, through June 30, 2027. The contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or by a vote of a majority of the outstanding voting securities of the Fund. Independent Expenses consist of the Fund’s allocable portion of the fees and expenses of the independent directors of the Corporation, counsel to such independent directors and the independent registered public accounting firm that provides audit services to the Fund. BlackRock has contractually agreed to reimburse, or provide offsetting credits to, the Fund for Independent Expenses through June 30, 2036. After giving effect to such contractual arrangements, Independent Expenses will be 0.00%. Such contractual arrangements may not be terminated prior to July 1, 2036 without the consent a majority of the non-interested directors of the Corporation (with 90 days’ notice) or by a vote of the majority of outstanding voting securities of the Fund. The Administration Fee for Class G Shares of the Fund is 0.015%. The Total Annual Fund Operating Expenses and the Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements is 0.025%. Returns for net indices generally assume the reinvestment of dividends after the deduction of the maximum withholding tax in each country applicable to non-residents of the country as determined by the index provider. Such indices use withholding tax rates that are often at a higher rate than the rates to which the Fund is subject in each country, including for countries where the Fund is not subject to withholding taxes. When this is the case, index performance will be lower than if the index used the Fund’s applicable withholding tax rates, if any. As described in the “Management of the Funds” section of the Fund’s prospectus beginning on page 42, BlackRock has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through June 30, 2027. In addition, BlackRock has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to BlackRock indirectly through its investment in money market funds managed by BlackRock or its affiliates, through June 30, 2027. The contractual agreements may be terminated upon 90 days’ notice by a majority of the non-interested directors of the Corporation or by a vote of a majority of the outstanding voting securities of the Fund. Independent Expenses consist of the Fund’s allocable portion of the fees and expenses of the independent directors of the Corporation, counsel to such independent directors and the independent registered public accounting firm that provides audit services to the Fund. BlackRock has contractually agreed to reimburse, or provide offsetting credits to, the Fund for Independent Expenses through June 30, 2036. After giving effect to such contractual arrangements, Independent Expenses will be 0.00%. Such contractual arrangements may not be terminated prior to July 1, 2036 without the consent a majority of the non-interested directors of the Corporation (with 90 days’ notice) or by a vote of the majority of outstanding voting securities of the Fund. Returns for net indices generally assume the reinvestment of dividends after the deduction of the maximum withholding tax in each country applicable to non-residents of the country as determined by the index provider. Such indices use withholding tax rates that are often at a higher rate than the rates to which the Fund is subject in each country, including for countries where the Fund is not subject to withholding taxes. When this is the case, index performance will be lower than if the index used the Fund’s applicable withholding tax rates, if any. The fees and expenses shown in the table and the example that follows include both the expenses of Russell 2000 Small-Cap Index Fund and Russell 2000 Small-Cap Index Fund’s share of the allocated expenses of Master Small Cap Index Series (the “Series”), a series of Quantitative Master Series LLC (the “Master LLC”). The management fees are paid by the Series.