Preliminary Pricing Supplement No. 15,670

Registration Statement Nos. 333-293641; 333-293641-01

Dated April 27, 2026

Filed pursuant to Rule 424(b)(2)

Morgan Stanley Finance LLC

Structured Investments

Conditional Lookback Entry Buffered PLUS with Downside Factor due October 29, 2030

Based on the Performance of the S&P 500® Futures Excess Return Index

Buffered Performance Leveraged Upside SecuritiesSM

Fully and Unconditionally Guaranteed by Morgan Stanley

Principal at Risk Securities

￭The Conditional Lookback Entry Buffered PLUS with Downside Factor (the “securities”) are unsecured obligations of Morgan Stanley Finance LLC (“MSFL”) and are fully and unconditionally guaranteed by Morgan Stanley. The securities will pay no interest, do not guarantee any return of principal at maturity and have the terms described in the accompanying product supplement, index supplement, tax supplement and prospectus, as supplemented or modified by this document.

￭Payment at maturity. At maturity, if a knock-in event has not occurred and (i) the final level is greater than the upside threshold level, then investors will receive the stated principal amount plus the leveraged upside payment with respect to the initial level, or (ii) the final level is equal to or less than the upside threshold level but the final level is greater than or equal to the buffer level, then investors will receive the stated principal amount. If a knock-in event has occurred and (i) the final level is greater than or equal to 105% of the conditional lookback level, investors will receive the stated principal amount plus the leveraged upside payment with respect to the conditional lookback level, or (ii) the final level is less than 105% of the conditional lookback level but greater than or equal to the buffer level, then investors will receive the stated principal amount. However, if the final level is less than the buffer level, then investors will lose 1.3333% for every 1% decline in the level of the underlier beyond the specified buffer amount. Under these circumstances, the payment at maturity will be less, and may be significantly less, than the stated principal amount and could be zero.

￭The securities are for investors who seek a return based on the performance of the underlier and who are willing to risk their principal and forgo current income in exchange for the conditional lookback feature used in adjusting the initial level, the upside leverage feature and the buffer feature that applies to any negative performance of the underlier over the term of the securities. Investors in the securities must be willing to accept the risk of losing their entire initial investment. The securities are notes issued as part of MSFL’s Series A Global Medium-Term Notes program.

￭All payments are subject to our credit risk. If we default on our obligations, you could lose some or all of your investment. These securities are not secured obligations and you will not have any security interest in, or otherwise have any access to, any underlying reference asset or assets.

TERMS
Issuer:	Morgan Stanley Finance LLC
Guarantor:	Morgan Stanley
Stated principal amount:	$1,000 per security
Issue price:	$1,000 per security (see “Commissions and issue price” below)
Aggregate principal amount:	$
Underlier:	S&P 500® Futures Excess Return Index (the “underlying index”)
Strike date:	April 24, 2026
Pricing date:	May 1, 2026
Original issue date:	May 6, 2026
Observation date:	October 24, 2030, subject to postponement for non-trading days and certain market disruption events
Maturity date:	October 29, 2030
	Terms continued on the following page
Agent:	Morgan Stanley & Co. LLC (“MS & Co.”), an affiliate of MSFL and a wholly owned subsidiary of Morgan Stanley. See “Supplemental information regarding plan of distribution; conflicts of interest.”
Estimated value on the pricing date:	Approximately $964.00 per security, or within $40.00 of that estimate. See “Estimated Value of the Securities” on page 3.
Commissions and issue price:	Price to public	Agent’s commissions and fees(1)(2)	Proceeds to us(3)
Per security	$1,000	$	$
Total	$	$	$

(1)The securities will be sold only to investors purchasing the securities in fee-based advisory accounts.

(2)MS & Co. expects to sell all of the securities that it purchases from us to an unaffiliated dealer at a price of $ per security, for further sale to certain fee-based advisory accounts at the price to public of $1,000 per security. MS & Co. will not receive a sales commission with respect to the securities. See “Supplemental information regarding plan of distribution; conflicts of interest.” For additional information, see “Plan of Distribution (Conflicts of Interest)” in the accompanying product supplement.

(3)See “Use of Proceeds and Hedging” in the accompanying product supplement.

The securities involve risks not associated with an investment in ordinary debt securities. See “Risk Factors” beginning on page 7.

The Securities and Exchange Commission and state securities regulators have not approved or disapproved these securities, or determined if this document or the accompanying product supplement, index supplement, tax supplement and prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The securities are not deposits or savings accounts and are not insured by the Federal Deposit Insurance Corporation or any other governmental agency or instrumentality, nor are they obligations of, or guaranteed by, a bank.

You should read this document together with the related product supplement, index supplement, tax supplement and prospectus, each of which can be accessed via the hyperlinks below. When you read the accompanying index supplement, please note that all references in such supplement to the prospectus dated November 16, 2023, or to any sections therein, should refer instead to the accompanying prospectus dated April 12, 2024 or to the corresponding sections of such prospectus, as applicable. Please also see “Additional Terms of the Securities” and “Additional Information About the Securities” at the end of this document.

References to “we,” “us” and “our” refer to Morgan Stanley or MSFL, or Morgan Stanley and MSFL collectively, as the context requires.

Product Supplement for Principal at Risk Securities dated April 8, 2026 Index Supplement dated April 8, 2026

Tax Supplement dated April 8, 2026 Prospectus dated April 8, 2026

 

Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

Terms continued from the previous page
Payment at maturity per security:	•If a knock-in event has not occurred, •If the final level is greater than or equal to the upside threshold level: stated principal amount + leveraged upside payment •If the final level is less than the upside threshold level but the final level is greater than or equal to the buffer level: stated principal amount •If a knock-in event has occurred, •If the final level is greater than or equal to 105% of the conditional lookback level: stated principal amount + leveraged upside payment •If the final level is less than 105% of the conditional lookback level but greater than or equal to the buffer level: stated principal amount •If the final level is less than the buffer level: stated principal amount × performance factor × downside factor Under these circumstances, the payment at maturity will be less, and may be significantly less, than the stated principal amount and could be zero.
Final level:	The closing level of the underlier on the observation date
Initial level:	577.43, which is the closing level on April 24, 2026
Knock-in level:	519.687, which is 90% of the initial level
Knock-in event:	A knock-in event has occurred if on any day during the initial observation period, the closing level of the underlier closes below the knock-in level.
Initial observation period:	Each business day on which there is no market disruption event from and including April 24, 2026 to and including October 26, 2026
Conditional lookback level:	If a knock-in event has occurred, the conditional lookback level will equal the product of (x) the initial level and (y) a fraction (expressed as a percentage), the numerator of which is the lowest closing level observed during the initial observation period and the denominator of which is the initial level, subject to a floor of 75%
Leveraged upside payment:	stated principal amount × leverage factor × underlier percent change
Leverage factor:	152%
Upside threshold level:	606.302, which is approximately 105% of the initial level
Underlier percent change:	If a knock-in event has not occurred, ●(final level – upside threshold level) / initial level If a knock-in event has occurred, ●[(final level – conditional lookback level) / conditional lookback level] - 5%
Buffer level:	433.073, which is approximately 75% of the initial level
Buffer amount:	25%
Downside factor:	1.3333
Performance factor:	final level / initial level
Minimum payment at maturity:	None
CUSIP:	61781FLF8
ISIN:	US61781FLF89
Listing:	The securities will not be listed on any securities exchange.

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

Estimated Value of the Securities

The original issue price of each security is $1,000. This price includes costs associated with issuing, selling, structuring and hedging the securities, which are borne by you, and, consequently, the estimated value of the securities on the pricing date will be less than $1,000. Our estimate of the value of the securities as determined on the pricing date will be within the range specified on the cover hereof and will be set forth on the cover of the final pricing supplement.

What goes into the estimated value on the pricing date?

In valuing the securities on the pricing date, we take into account that the securities comprise both a debt component and a performance-based component linked to the underlier. The estimated value of the securities is determined using our own pricing and valuation models, market inputs and assumptions relating to the underlier, instruments based on the underlier, volatility and other factors including current and expected interest rates, as well as an interest rate related to our secondary market credit spread, which is the implied interest rate at which our conventional fixed rate debt trades in the secondary market.

What determines the economic terms of the securities?

In determining the economic terms of the securities, we use an internal funding rate, which is likely to be lower than our secondary market credit spreads and therefore advantageous to us. If the issuing, selling, structuring and hedging costs borne by you were lower or if the internal funding rate were higher, one or more of the economic terms of the securities would be more favorable to you.

What is the relationship between the estimated value on the pricing date and the secondary market price of the securities?

The price at which MS & Co. purchases the securities in the secondary market, absent changes in market conditions, including those related to the underlier, may vary from, and be lower than, the estimated value on the pricing date, because the secondary market price takes into account our secondary market credit spread as well as the bid-offer spread that MS & Co. would charge in a secondary market transaction of this type and other factors. However, because the costs associated with issuing, selling, structuring and hedging the securities are not fully deducted upon issuance, to the extent that MS & Co. may buy or sell the securities in the secondary market during the amortization period specified herein, absent changes in market conditions, including those related to the underlier, and to our secondary market credit spreads, it would do so based on values higher than the estimated value. We expect that those higher values will also be reflected in your brokerage account statements.

MS & Co. may, but is not obligated to, make a market in the securities, and, if it once chooses to make a market, may cease doing so at any time.

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

Hypothetical Examples

The following hypothetical examples illustrate how to calculate the hypothetical payment at maturity, if any, with respect to the securities. The following examples are for illustrative purposes only. The payment at maturity will be determined by reference to several factors, including the conditional lookback level and the final level. The actual initial level, call threshold level, coupon barrier level and buffer level will be determined at the end of the initial observation period. All payments on the securities are subject to our credit risk. The numbers in the hypothetical examples below may have been rounded for ease of analysis. The below examples are based on the following terms.

Stated principal amount:	$1,000 per security
Leverage factor:	152%
Hypothetical initial level:	100.00*
Hypothetical conditional lookback level:	75.00**, which is 75% of the hypothetical initial level
Hypothetical upside threshold level:	105.00, which is 105% of the hypothetical initial level
Hypothetical buffer level:	75.00, which is 75% of the hypothetical initial level
Buffer amount:	25%
Downside factor:	1.3333%

*The hypothetical initial level of 100.00 has been chosen for illustrative purposes only and does not represent the actual initial level. Please see “Historical Information” below for historical data regarding the actual closing levels.

**The hypothetical conditional lookback level of 75.00 has been chosen for all of the below examples.

	Hypothetical closing level	A Knock-In Event has not occurred		A Knock-In Event has occurred
		Payment at Maturity per Security	Return on the Securities	Payment at Maturity per Security	Return on the Securities
Example #1	$150.00	$1,684.00	68.40%	$2,444.00	144.40%
Example #2	$100.00	$1,000	0%	$1,430.67	43.067%
Example #3	$80.00	$1,000	0%	$1,025.33	2.533%
Example #4	$75.00	$1,000	0%	$1,000	0%
Example #5	$74.00	$986.67	-1.33%	$986.67	-1.33%
Example #6	$50.00	$666.68	-33.333%	$666.68	-33.333%

In example #1, the final level is 150.00.

If a knock-in event has not occurred, the final level is greater than or equal to the buffer level and greater than or equal to the upside threshold level. As a result, investors will receive at maturity the stated principal amount plus the leveraged upside payment.

If a knock-in event has occurred, the final level is greater than or equal to the buffer level and greater than or equal to 105% of the conditional lookback level. As a result, investors will receive at maturity the stated principal amount plus the leveraged upside payment.

In example #2, the final level is 100.00.

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

If a knock-in event has not occurred, the final level is greater than or equal to the buffer level but less than the upside threshold level. As a result, investors will receive at maturity only the stated principal amount.

If a knock-in event has occurred, the final level is greater than or equal to the buffer level and greater than or equal to 105% of the conditional lookback level. As a result, investors will receive at maturity the stated principal amount plus the leveraged upside payment.

In example #3, the final level is 80.00.

If a knock-in event has not occurred, the final level is greater than or equal to the buffer level but less than the upside threshold level. As a result, investors will receive at maturity only the stated principal amount.

If a knock-in event has occurred, the final level is greater than or equal to the buffer level and greater than or equal to 105% of the conditional lookback level. As a result, investors will receive at maturity the stated principal amount plus the leveraged upside payment.

In example #4, the final level is 75.00.

If a knock-in event has not occurred, the final level is greater than or equal to the buffer level but less than the upside threshold level. As a result, investors will receive at maturity only the stated principal amount.

If a knock-in event has occurred, the final level is greater than or equal to the buffer level but less than 105% of the conditional lookback level. As a result, investors will receive at maturity only the stated principal amount.

In example #5, the final level is 74.00.

The final level is less than the buffer level. As a result, investors will receive at maturity a payment that reflects a loss of 1.3333% of principal for each 1% decline in the level beyond the buffer amount.

In example #6, the final level is 50.00.

The final level is less than the buffer level. As a result, investors will receive at maturity a payment that reflects a loss of 1.3333% of principal for each 1% decline in the level beyond the buffer amount.

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

Risk Factors

This section describes the material risks relating to the securities. For further discussion of these and other risks, you should read the section entitled “Risk Factors” in the accompanying product supplement, tax supplement and prospectus. We also urge you to consult with your investment, legal, tax, accounting and other advisers in connection with your investment in the securities.

Risks Relating to an Investment in the Securities

￭The securities do not guarantee the return of any principal and do not pay interest. The terms of the securities differ from those of ordinary debt securities in that they do not guarantee the repayment of any principal and do not pay interest. If the final level is less than the buffer level, the payout at maturity will be an amount in cash that is less, and may be significantly less, than the stated principal amount of each security, and you will lose an amount proportionate to the decline in the level of the underlier over the term of the securities beyond the buffer amount multiplied by the downside factor. There is no minimum payment at maturity on the securities, and, accordingly, you could lose your entire initial investment in the securities.

￭The conditional lookback level will not be determined until the end of the initial observation period. Because the conditional lookback level will be the lowest closing level during the initial observation period, the conditional lookback level will not be determined until the end of the initial observation period. Accordingly, you will not know the conditional lookback level for a significant period of time after the strike date. In no event, however, will the conditional lookback level be greater than the closing level of the underlier on the strike date.

￭The amount payable on the securities is not linked to the value of the underlier at any time other than the observation date. The final level will be based on the closing level of the underlier on the observation date, subject to postponement for non-trading days and certain market disruption events. Even if the value of the underlier appreciates prior to the observation date but then drops by the observation date, the payment at maturity may be less, and may be significantly less, than it would have been had the payment at maturity been linked to the value of the underlier prior to such drop. Although the actual value of the underlier on the stated maturity date or at other times during the term of the securities may be higher than the closing level of the underlier on the observation date, the payment at maturity will be based solely on the closing level of the underlier on the observation date.

￭The market price of the securities may be influenced by many unpredictable factors. Several factors, many of which are beyond our control, will influence the value of the securities in the secondary market and the price at which MS & Co. may be willing to purchase or sell the securities in the secondary market. We expect that generally the value of the underlier at any time will affect the value of the securities more than any other single factor. Other factors that may influence the value of the securities include:

othe volatility (frequency and magnitude of changes in value) of the underlier;

ointerest and yield rates in the market;

ogeopolitical conditions and economic, financial, political, regulatory or judicial events that affect the underlier or markets generally;

othe availability of comparable instruments;

othe composition of the underlier and changes in such composition;

othe time remaining until the securities mature; and

oany actual or anticipated changes in our credit ratings or credit spreads.

Some or all of these factors will influence the price that you will receive if you sell your securities prior to maturity. Generally, the longer the time remaining to maturity, the more the market price of the securities will be affected by the other factors described above. For example, you may have to sell your securities at a substantial discount from the stated principal amount if, at the time of sale, the closing level of the underlier is at, below or not sufficiently above the buffer level, or if market interest rates rise.

You can review the historical closing levels of the underlier in the section of this document called “Historical Information.” You cannot predict the future performance of the underlier based on its historical performance. The value of the underlier may be, and has recently been, volatile, and we can give you no assurance that the volatility will lessen. There can be no assurance that the final level will be greater than or equal to the buffer level so that you do not suffer a loss of some or all of your initial investment in the securities.

￭The securities are subject to our credit risk, and any actual or anticipated changes to our credit ratings or credit spreads may adversely affect the market value of the securities. You are dependent on our ability to pay all amounts due on the securities, and, therefore, you are subject to our credit risk. The securities are not guaranteed by any other entity. If we default on our obligations under the securities, your investment would be at risk and you could lose some or all of your investment. As a result, the market value of the securities prior to maturity will be affected by changes in the market’s view of our creditworthiness. Any actual or anticipated decline in our credit ratings or increase in the credit spreads charged by the market for taking our credit risk is likely to adversely affect the market value of the securities.

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

￭As a finance subsidiary, MSFL has no independent operations and will have no independent assets. As a finance subsidiary, MSFL has no independent operations beyond the issuance and administration of its securities and will have no independent assets available for distributions to holders of MSFL securities if they make claims in respect of such securities in a bankruptcy, resolution or similar proceeding. Accordingly, any recoveries by such holders will be limited to those available under the related guarantee by Morgan Stanley and that guarantee will rank pari passu with all other unsecured, unsubordinated obligations of Morgan Stanley. Holders will have recourse only to a single claim against Morgan Stanley and its assets under the guarantee. Holders of securities issued by MSFL should accordingly assume that in any such proceedings they would not have any priority over and should be treated pari passu with the claims of other unsecured, unsubordinated creditors of Morgan Stanley, including holders of Morgan Stanley-issued securities.

￭The rate we are willing to pay for securities of this type, maturity and issuance size is likely to be lower than the rate implied by our secondary market credit spreads and advantageous to us. Both the lower rate and the inclusion of costs associated with issuing, selling, structuring and hedging the securities in the original issue price reduce the economic terms of the securities, cause the estimated value of the securities to be less than the original issue price and will adversely affect secondary market prices. Assuming no change in market conditions or any other relevant factors, the prices, if any, at which dealers, including MS & Co., may be willing to purchase the securities in secondary market transactions will likely be significantly lower than the original issue price, because secondary market prices will exclude the issuing, selling, structuring and hedging-related costs that are included in the original issue price and borne by you and because the secondary market prices will reflect our secondary market credit spreads and the bid-offer spread that any dealer would charge in a secondary market transaction of this type as well as other factors.

The inclusion of the costs of issuing, selling, structuring and hedging the securities in the original issue price and the lower rate we are willing to pay as issuer make the economic terms of the securities less favorable to you than they otherwise would be.

However, because the costs associated with issuing, selling, structuring and hedging the securities are not fully deducted upon issuance, to the extent that MS & Co. may buy or sell the securities in the secondary market during the amortization period specified herein, absent changes in market conditions, including those related to the underlier, and to our secondary market credit spreads, it would do so based on values higher than the estimated value, and we expect that those higher values will also be reflected in your brokerage account statements.

￭The estimated value of the securities is determined by reference to our pricing and valuation models, which may differ from those of other dealers and is not a maximum or minimum secondary market price. These pricing and valuation models are proprietary and rely in part on subjective views of certain market inputs and certain assumptions about future events, which may prove to be incorrect. As a result, because there is no market-standard way to value these types of securities, our models may yield a higher estimated value of the securities than those generated by others, including other dealers in the market, if they attempted to value the securities. In addition, the estimated value on the pricing date does not represent a minimum or maximum price at which dealers, including MS & Co., would be willing to purchase your securities in the secondary market (if any exists) at any time. The value of your securities at any time after the date of this document will vary based on many factors that cannot be predicted with accuracy, including our creditworthiness and changes in market conditions. See also “The market price of the securities may be influenced by many unpredictable factors” above.

￭The securities will not be listed on any securities exchange and secondary trading may be limited. The securities will not be listed on any securities exchange. Therefore, there may be little or no secondary market for the securities. MS & Co. may, but is not obligated to, make a market in the securities and, if it once chooses to make a market, may cease doing so at any time. When it does make a market, it will generally do so for transactions of routine secondary market size at prices based on its estimate of the current value of the securities, taking into account its bid/offer spread, our credit spreads, market volatility, the notional size of the proposed sale, the cost of unwinding any related hedging positions, the time remaining to maturity and the likelihood that it will be able to resell the securities. Even if there is a secondary market, it may not provide enough liquidity to allow you to trade or sell the securities easily. Since other broker-dealers may not participate significantly in the secondary market for the securities, the price at which you may be able to trade your securities is likely to depend on the price, if any, at which MS & Co. is willing to transact. If, at any time, MS & Co. were to cease making a market in the securities, it is likely that there would be no secondary market for the securities. Accordingly, you should be willing to hold your securities to maturity.

￭As discussed in more detail in the accompanying product supplement, investing in the securities is not equivalent to investing in the underlier(s).

￭The U.S. federal income tax consequences of an investment in the securities offered by this pricing supplement are uncertain. There is no direct legal authority regarding the proper U.S. federal income tax treatment of the securities, and significant aspects of the tax treatment of the securities are uncertain. In particular, due to the terms of the securities and current market conditions, there is a substantial risk that the securities could be characterized as debt instruments for U.S. federal income tax purposes, in which case the timing and character of income recognized in respect of the securities could be different from those described herein and possibly adverse to certain investors. You should review carefully the section entitled “United States Federal Income Tax Considerations” herein, in combination with the section entitled “United States Federal Taxation” in the accompanying

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

tax supplement, and consult your tax adviser regarding the U.S. federal income tax consequences of an investment in the securities.

Risks Relating to the Underlier(s)

￭Because your return on the securities will depend upon the performance of the underlier(s), the securities are subject to the following risk(s), as discussed in more detail in the accompanying product supplement.

oHigher future prices of a futures contract to which the underlier is linked relative to its current prices may adversely affect the value of the underlier and the value of the securities.

oSuspensions or disruptions of market trading in futures markets could adversely affect the value of the securities.

oLegal and regulatory changes could adversely affect the return on and value of the securities.

￭Adjustments to the S&P 500® Futures Excess Return Index could adversely affect the value of the securities. As the underlying index publisher for the S&P 500® Futures Excess Return Index, S&P® Dow Jones Indices LLC can make methodological changes that could change the value of such underlying index. Any of these actions could adversely affect the value of the securities. An underlying index publisher has no obligation to consider your interests in calculating or revising an underlying index. An underlying index publisher may discontinue or suspend calculation or publication of an underlying index at any time. In these circumstances, MS & Co., as the calculation agent, will have the sole discretion to substitute a successor index that is comparable to the discontinued underlying index. MS & Co. could have an economic interest that is different than that of investors in the securities insofar as, for example, MS & Co. is permitted to consider indices that are calculated and published by MS & Co. or any of its affiliates.

Risks Relating to Conflicts of Interest

In engaging in certain activities described below and as discussed in more detail in the accompanying product supplement, our affiliates may take actions that may adversely affect the value of and your return on the securities, and in so doing they will have no obligation to consider your interests as an investor in the securities.

￭The calculation agent, which is a subsidiary of Morgan Stanley and an affiliate of MSFL, will make determinations with respect to the securities. As calculation agent, MS & Co. will make any determinations necessary to calculate any payment(s) on the securities. Moreover, certain determinations made by MS & Co., in its capacity as calculation agent, may require it to exercise discretion and make subjective judgments, which may adversely affect your return on the securities. In addition, MS & Co. has determined the estimated value of the securities on the pricing date.

￭Hedging and trading activity by our affiliates could potentially adversely affect the value of the securities.

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

Historical Information

S&P 500® Futures Excess Return Index Overview

Bloomberg Ticker Symbol: SPXFP

The S&P 500® Futures Excess Return Index is an equity futures index that measures the performance of the nearest maturing quarterly E-mini S&P 500 futures contract (its “futures contract”) trading on the Chicago Mercantile Exchange. The underlying index publisher with respect to the S&P 500® Futures Excess Return Index is S&P® Dow Jones Indices LLC, or any successor thereof. E-mini S&P 500 futures contracts are U.S. dollar-denominated futures contracts based on the performance of the S&P 500® Index (its “reference index”). For additional information about the S&P 500® Index and how it is calculated and maintained, see “S&P® U.S. Indices—S&P 500® Index” in the accompanying index supplement. For additional information about the S&P 500® Futures Excess Return Index, see the information set forth under “S&P 500® Futures Excess Return Index” in the accompanying index supplement.

The closing level of the underlier on April 24, 2026 was 577.43. The following graph sets forth the daily closing levels of the underlier for the period noted below. We obtained the historical information presented in this document from Bloomberg Financial Markets, without independent verification. The underlier has at times experienced periods of high volatility. You should not take the historical closing levels of the underlier as an indication of its future performance, and no assurance can be given as to the closing level of the underlier at any time.

Underlier Daily Closing Levels January 1, 2021 to April 24, 2026

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

Additional Terms of the Securities

Please read this information in conjunction with the terms on the cover of this document.

Additional Terms:
If the terms described herein are inconsistent with those described in the accompanying product supplement, index supplement, tax supplement or prospectus, the terms described herein shall control.
Denominations:	$1,000 per security and integral multiples thereof
Conditional Lookback Entry Buffered PLUS with Downside Factor:	The accompanying product supplement refers to these Conditional Lookback Entry Buffered PLUS with Downside Factor as the “securities.”
Amortization period:	The 6-month period following the issue date
Trustee:	The Bank of New York Mellon
Calculation agent:	Morgan Stanley & Co. LLC (“MS & Co.”)

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

Additional Information About the Securities

Additional Information:
Minimum ticketing size:	$1,000 / 1 security
United States federal income tax considerations:	You should review carefully the section in the accompanying tax supplement entitled “United States Federal Taxation.” The following discussion, when read in combination with that section, constitutes the full opinion of our counsel, Davis Polk & Wardwell LLP, regarding the material U.S. federal income tax consequences of owning and disposing of the securities offered by this pricing supplement. Generally, this discussion assumes that you purchased a security for cash in the original issuance at the stated issue price and does not address other circumstances specific to you, including consequences that may arise due to any other investments relating to an underlier. Moreover, as discussed in the section entitled “United States Federal Taxation” in the accompanying tax supplement, we have not attempted to ascertain whether any issuer of any underlier to which the securities relate is a U.S. real property holding corporation or a passive foreign investment company. You should consult your tax adviser regarding these issues, including the effect any circumstances specific to you may have on the U.S. federal income tax consequences of your ownership of a security. In the opinion of our counsel, which is based on current market conditions, it is reasonable to treat the securities for U.S. federal income tax purposes as prepaid financial contracts that are “open transactions,” as described in the section entitled “United States Federal Taxation—Tax Consequences to U.S. Holders—Program Securities Treated as Prepaid Financial Contracts that are Open Transactions” in the accompanying tax supplement. There is uncertainty regarding this treatment, and the Internal Revenue Service (the “IRS”) or a court might not agree with it. Moreover, because this treatment of the securities and our counsel’s opinion are based on market conditions as of the date of this preliminary pricing supplement, each is subject to confirmation on the pricing date. A different tax treatment could be adverse to you. Generally, if this treatment is respected, (i) you should not recognize taxable income or loss prior to the taxable disposition of your securities (including upon maturity or an earlier redemption, if applicable) and (ii) the gain or loss on your securities generally should be treated as capital gain or loss. We do not plan to request a ruling from the IRS regarding the treatment of the securities. An alternative characterization of the securities could materially and adversely affect the tax consequences of ownership and disposition of the securities, including the timing and character of income recognized. In particular, due to the terms of the securities and current market conditions, there is a substantial risk that the securities could be characterized as debt instruments for U.S. federal income tax purposes, in which case the timing and character of income recognized in respect of the securities could be different from those described herein and possibly adverse to certain investors. In addition, the U.S. Treasury Department and the IRS have requested comments on various issues regarding the U.S. federal income tax treatment of “prepaid forward contracts” and similar financial instruments and have indicated that such transactions may be the subject of future regulations or other guidance. Furthermore, members of Congress have proposed legislative changes to the tax treatment of derivative contracts. Any legislation, Treasury regulations or other guidance promulgated after consideration of these issues could materially and adversely affect the tax consequences of an investment in the securities, possibly with retroactive effect. Non-U.S. Holders. If you are a Non-U.S. Holder (as defined in the accompanying tax supplement), please also read the section entitled “United States Federal Taxation—Tax Consequences to Non-U.S. Holders—Program Securities Not Treated as Debt Instruments” in the accompanying tax supplement. As discussed under “United States Federal Taxation—Tax Consequences to Non-U.S. Holders—Dividend Equivalents under Section 871(m) of the Code” in the accompanying tax supplement, Section 871(m) of the Internal Revenue Code and Treasury regulations promulgated thereunder (“Section 871(m)”) generally impose a 30% withholding tax on dividend equivalents paid or deemed paid to Non-U.S. Holders with respect to certain financial instruments linked to U.S. equities or indices that include U.S. equities. The Treasury regulations, as modified by an IRS notice, exempt financial instruments issued prior to January 1, 2027 that do not have a “delta” of one. Based on certain determinations made by us, we expect that Section 871(m) will not apply to the securities with regard to Non-U.S. Holders. Our determination is not binding on the IRS, and the IRS may disagree with this determination. If necessary, further information regarding the potential application of Section 871(m) will be provided in the final pricing supplement for the securities. We will not be required to pay any additional amounts with respect to U.S. federal withholding taxes.

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Morgan Stanley Finance LLC

Conditional Lookback Entry Buffered PLUS with Downside Factor Principal at Risk Securities

 

	You should consult your tax adviser regarding the U.S. federal income tax consequences of an investment in the securities, including possible alternative treatments, as well as tax consequences arising under the laws of any state, local or non-U.S. taxing jurisdiction.
Additional considerations:	Client accounts over which Morgan Stanley, Morgan Stanley Wealth Management or any of their respective subsidiaries have investment discretion are not permitted to purchase the securities, either directly or indirectly.
Supplemental information regarding plan of distribution; conflicts of interest:	MS & Co. expects to sell all of the securities that it purchases from us to an unaffiliated dealer at a price of $ per security, for further sale to certain fee-based advisory accounts at the price to public of $1,000 per security. MS & Co. will not receive a sales commission with respect to the securities. MS & Co. is an affiliate of MSFL and a wholly owned subsidiary of Morgan Stanley, and it and other affiliates of ours expect to make a profit by selling, structuring and, when applicable, hedging the securities. MS & Co. will conduct this offering in compliance with the requirements of FINRA Rule 5121 of the Financial Industry Regulatory Authority, Inc., which is commonly referred to as FINRA, regarding a FINRA member firm’s distribution of the securities of an affiliate and related conflicts of interest. MS & Co. or any of our other affiliates may not make sales in this offering to any discretionary account. See “Plan of Distribution (Conflicts of Interest)” and “Use of Proceeds and Hedging” in the accompanying product supplement.
Where you can find more information:	Morgan Stanley and MSFL have filed a registration statement (including a prospectus, as supplemented by the product supplement, the index supplement and the tax supplement) with the Securities and Exchange Commission (the “SEC”) for the offering to which this communication relates. You should read the prospectus in that registration statement, the product supplement, the index supplement, the tax supplement and any other documents relating to this offering that MSFL and Morgan Stanley have filed with the SEC for more complete information about Morgan Stanley and this offering. You may get these documents without cost by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, MSFL, Morgan Stanley, any underwriter or any dealer participating in the offering will arrange to send you the prospectus, the index supplement, the product supplement and the tax supplement if you so request by calling toll-free 1-(800)-584-6837. Terms used but not defined in this document are defined in the product supplement, in the index supplement, in the tax supplement or in the prospectus. Each of the product supplement, the index supplement, the tax supplement and the prospectus can be accessed via the hyperlinks set forth on the cover of this document. “Performance Leveraged Upside Securities℠” and “PLUS℠” are our service marks.

 

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