497K - NVIT Fidelity Institutional AM?Worldwide Fund

NVIT Fidelity Institutional AM® Worldwide Fund

Summary Prospectus April 30, 2026

Class I / Class II

Before you invest, you may want to review the Fund’s Prospectus, which contains information about the Fund and its risks. This Summary Prospectus is intended for use in connection with variable insurance contracts, and is not intended for use by other investors. The Fund’s Prospectus and Statement of Additional Information, each dated April 30, 2026 (as may be supplemented or revised), are incorporated by reference into this Summary Prospectus. For free paper or electronic copies of the Fund’s Prospectus and other information about the Fund, go to nationwide.com/mutualfundsnvit, email a request to web_help@nationwide.com or call 800-848-0920, or ask any variable insurance contract provider who offers shares of the Fund as an underlying investment option in its products.

Objective

The NVIT Fidelity Institutional AM® Worldwide Fund (the “Fund”) seeks capital growth.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. Sales charges and other expenses that may be imposed by variable insurance contracts are not included. If these charges were reflected, the expenses listed below would be higher. See the variable insurance contract prospectus, which may impose sales charges and other additional contract-level expenses.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class I Shares	Class II Shares
Management Fees	0.46%	0.46%
Distribution and/or Service (12b-1) Fees	None	0.25%
Other Expenses	0.58%	0.58%
Total Annual Fund Operating Expenses	1.04%	1.29%
Fee Waiver/Expense Reimbursement(1)	(0.24)%	(0.24)%
Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement	0.80%	1.05%

(1) Nationwide Variable Insurance Trust (the “Trust”) and Nationwide Fund Advisors (the “Adviser”) have entered into a written contract limiting annual fund operating expenses to 0.55% until at

least April 30, 2027. Under the expense limitation agreement, the level to which operating expenses are limited applies to all share classes, excluding any taxes, interest, compensation payable

to parties not affiliated with the Adviser for the recovery of tax reclaims, brokerage commissions, Rule 12b-1 fees, acquired fund fees and expenses, short-sale dividend expenses, administrative services fees, other expenses which are capitalized in accordance with generally accepted accounting principles and expenses incurred by the Fund in connection with any merger or reorganization, and may exclude other nonroutine expenses not incurred in the ordinary course of the Fund’s business. The expense limitation agreement may be changed or eliminated only with the consent of the Board of Trustees of the Trust. The Adviser may request and receive reimbursement from the Fund for advisory fees waived or other expenses reimbursed by the Adviser pursuant to the expense limitation agreement at a date not to exceed three years from the date on which the corresponding waiver or reimbursement to the Fund was made. However, no reimbursement may be made unless: (i) the Fund’s assets exceed $100 million and (ii) the total annual expense ratio is no higher than the amount of the expense limitation that was in place at the time the Adviser waived the fees or reimbursed the expenses and does not cause the expense ratio to exceed the current expense limitation. Reimbursement by the Fund of amounts previously waived or reimbursed by the Adviser is not permitted except as provided for in the expense limitation agreement.

Example

This Example is intended to help you to compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example, however, does not include charges that are imposed by variable insurance contracts. If these charges were reflected, the expenses listed below would be higher.

This Example assumes that you invest $10,000 in the Fund for the time periods indicated and then sell all of your shares at the end of those time periods. It assumes a 5% return each year and no change in expenses, and any expense limitation or fee waivers

NSP-AMWW (4/26)

Summary Prospectus April 30, 2026

NVIT Fidelity Institutional AM® Worldwide Fund

that may apply for the periods indicated above under “Fees and Expenses.” Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 Year	3 Years	5 Years	10 Years
Class I Shares	$82	$307	$551	$1,249
Class II Shares	107	385	685	1,535

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. During the period April 15, 2025 (commencement of operations) through December 31, 2025, the Fund’s portfolio turnover rate was 90.45% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests in equity securities of companies located throughout the world, including the United States. Under normal market conditions, the Fund’s subadviser invests the Fund’s assets primarily in common stocks. The Fund may invest in issuers of any market capitalization, including smaller companies. The Fund typically invests in at least five countries including the United States. The Fund also may invest in emerging market countries. Emerging market countries typically are developing and low- or middle-income countries, and may be found in regions such as Asia, Latin America, Eastern Europe, the Middle East and Africa. Many of the securities in which the Fund invests are denominated in currencies other than the U.S. dollar. The Fund’s subadviser normally allocates the Fund’s investments across different countries and regions. The Fund may have significant investments in one or more countries or in particular sectors.

In buying and selling securities for the Fund, the subadviser relies on fundamental analysis, which involves a bottom-up assessment of a company’s potential for success in light of factors including its financial condition, earnings outlook, strategy, management, industry position, and economic and market conditions. The Fund may engage in frequent and active trading of portfolio securities.

Principal Risks

The Fund cannot guarantee that it will achieve its investment objective.

As with any fund, the value of the Fund’s investments—and therefore, the value of Fund shares—may fluctuate. These changes may occur because of:

Equity securities risk – stock markets are volatile. The price of an equity security fluctuates based on changes in a company’s financial condition and overall market and economic conditions.

Foreign securities risk – foreign securities often are more volatile, harder to price and less liquid than U.S. securities.

Foreign currencies – foreign securities may be denominated or quoted in currencies other than the U.S. dollar. Changes in foreign currency exchange rates affect the value of the Fund’s portfolio. Generally, when the U.S. dollar rises in value against a foreign currency, a security denominated in that currency loses value because the currency is worth fewer U.S. dollars. Conversely, when the U.S. dollar decreases in value against a foreign currency, a security denominated in that currency gains value because the currency is worth more U.S. dollars.

Market risk – the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. This occurs due to numerous factors, including interest rates, the outlook for corporate profits, the health of the national and world economies, and the fluctuation of other securities markets around the world. These risks may be magnified if certain social, political, economic and other conditions and events (such as natural disasters, epidemics and pandemics, terrorism, conflicts, trade disputes and social unrest or rapid technological developments such as artificial intelligence) adversely interrupt the global economy.

Smaller company risk – smaller companies are usually less stable in price and less liquid than larger, more established companies. Smaller companies are more vulnerable than larger companies to adverse business and economic developments and may have more limited resources. Therefore, they generally involve greater risk.

Selection risk – the risk that the securities selected by the Fund’s subadviser will underperform the markets, the relevant indexes or the securities selected by other funds with similar investment objectives and investment strategies.

Summary Prospectus April 30, 2026

NVIT Fidelity Institutional AM® Worldwide Fund

Emerging markets risk – emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. Investments in emerging markets are considered speculative. Emerging markets are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging securities markets have far lower trading volumes and less liquidity than developed markets. Since these markets are smaller than developed markets, they may be more likely to suffer sharp and frequent price changes or long-term price depression because of adverse publicity, investor perceptions or the actions of a few large investors. Practices in relation to settlement of securities transactions in emerging markets involve higher risks than those in developed markets, in part because the Fund will need to use brokers and counterparties that are less well capitalized, and custody and registration of assets in some countries are unreliable compared to developed markets. Companies in emerging market countries generally are subject to less stringent financial reporting, accounting and auditing standards than companies in more developed countries. In addition, information about such companies may be less available and reliable. Many emerging markets also have histories of political instability and abrupt changes in policies, and the ability to bring and enforce actions may be limited. Certain emerging markets also face other significant internal or external risks, including the risk of war, nationalization of assets, unexpected market closures and ethnic, religious and racial conflicts.

Country or sector risk– if the Fund emphasizes one or more countries or economic sectors, it will be more susceptible to the financial, market or economic events affecting the particular issuers in which it invests than funds that do not emphasize particular countries or sectors.

Portfolio turnover risk – a higher portfolio turnover rate increases transaction costs and may adversely impact the Fund’s performance.

Loss of money is a risk of investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Performance

Performance information gives some indication of the risks of an investment in the Fund by comparing the Fund’s performance with a broad measure of market performance. Performance information is not provided because the Fund is new and did not complete one full calendar year of operations.

The Fund’s broad-based securities market index is the MSCI All Country World Index in order to meet a Securities and Exchange Commission requirement. The Fund also compares its performance to the MSCI World Index - Net Return, which has characteristics relevant to the Fund’s investment strategy.

Portfolio Management

Investment Adviser

Nationwide Fund Advisors

Subadviser

FIAM LLC

Portfolio Managers

Portfolio Manager	Title	Length of Service
Stephen A. DuFour	Co-Portfolio Manager	Since 2025
Andrew A. Sergeant	Co-Portfolio Manager	Since 2025

Tax Information

The dividends and distributions paid by the Fund to the insurance company separate accounts will consist of ordinary income, capital gains, or some combination of both. Because shares of the Fund must be purchased through separate accounts used to fund variable insurance contracts, such dividends and distributions will be exempt from current taxation by contract holders if left to accumulate within a separate account. Consult the variable insurance contract prospectus for additional tax information.

Payments to Broker-Dealers and Other Financial Intermediaries

This Fund is only offered as an underlying investment option for variable insurance contracts. The Fund and its related companies may make payments to the sponsoring insurance companies (or their affiliates) for distribution and/or other services, and to broker-dealers and other financial intermediaries that distribute the variable insurance contracts. These payments may create a conflict of interest by influencing the insurance companies to include the Fund as an underlying investment option in the variable insurance contracts, and by influencing the broker-dealers and other financial intermediaries to distribute variable insurance contracts that include the Fund as an underlying investment option over other variable insurance contracts or to otherwise recommend the selection of the Fund as an underlying investment option by contract owners instead of other funds that also may be available investment options. The prospectus (or other offering document) for your variable insurance contract may contain additional information about these payments.

Summary Prospectus April 30, 2026

NVIT Fidelity Institutional AM® Worldwide Fund