JNL Series Trust

04/27/2026 | Press release | Distributed by Public on 04/27/2026 07:18

Summary Prospectus by Investment Company (Form 497K)

Summary Prospectus - April 27, 2026

JNL/MFS Equity Income Fund

(formerly, JNL/Invesco Diversified Dividend Fund)

Class A

Class I

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund, including the Statement of Additional Information ("SAI") and most recent reports to shareholders, online at https://www.jackson.com/fund-literature.html. You can also get this information at no cost by calling 1-800-644-4565 (Annuity and Life Service Center), 1-800-599-5651 (NY Annuity and Life Service Center), 1-800-777-7779 (for contracts purchased through a bank or financial institution) or 1-888-464-7779 (for NY contracts purchased through a bank or financial institution), or by sending an email request to [email protected]. The current Prospectus and SAI, both dated April 27, 2026, as amended, are incorporated by reference into (which means they legally are a part of) this Summary Prospectus.

Investment Objective. The investment objective of the Fund is to seek total return through a combination of current income and capital appreciation.

Expenses. This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund.

The expenses do not reflect the expenses of the variable insurance contracts or the separate account through which you indirectly invest in the Fund, whichever may be applicable, and the total expenses would be higher if they were included.

You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

Shareholder Fees
(fees paid directly from your investment)

Not Applicable

Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Class A
Management Fee 0.46%
Distribution and/or Service (12b-1) Fees 0.30%
Other Expenses1 0.15%
Acquired Fund Fees and Expenses2 0.01%
Total Annual Fund Operating Expenses3 0.92%
1 "Other Expenses" include an Administrative Fee of 0.15% which is payable to Jackson National Asset Management, LLC ("JNAM" or "Adviser").
2 Acquired Fund Fees and Expenses are the indirect expenses of investing in other investment companies. Accordingly, the expense ratio presented in the Financial Highlights section of the prospectus will not correlate to the Total Annual Fund Operating Expenses disclosed above.
3 Expense information has been restated to reflect current fees.
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Class I
Management Fee 0.46%
Distribution and/or Service (12b-1) Fees 0.00%
Other Expenses1 0.15%
Acquired Fund Fees and Expenses2 0.01%
Total Annual Fund Operating Expenses3 0.62%
1 "Other Expenses" include an Administrative Fee of 0.15% which is payable to Jackson National Asset Management, LLC ("JNAM" or "Adviser").
2 Acquired Fund Fees and Expenses are the indirect expenses of investing in other investment companies. Accordingly, the expense ratio presented in the Financial Highlights section of the prospectus will not correlate to the Total Annual Fund Operating Expenses disclosed above.
3 Expense information has been restated to reflect current fees.

Expense Example. This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. Also, this example does not reflect the expenses of the variable insurance contracts or the separate account through which you indirectly invest in the Fund, whichever may be applicable, and the total expenses would be higher if they were included. The table below shows the expenses you would pay on a $10,000 investment, assuming (1) 5% annual return; (2) redemption at the

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end of each time period; and (3) that the Fund operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

JNL/MFS Equity Income Fund Class A
1 year 3 years 5 years 10 years
$94 $293 $509 $1,131
JNL/MFS Equity Income Fund Class I
1 year 3 years 5 years 10 years
$63 $199 $346 $774

Portfolio Turnover (% of average value of portfolio). 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 Expense Example above, affect the Fund's performance.

Period
1/1/2025 - 12/31/2025 59 %

Portfolio turnover for the period of January 1, 2025 to December 31, 2025 is for the Fund when operating under its former investment strategy.

Principal Investment Strategies. Under normal circumstances, the Fund invests at least 80% of its assets (net assets plus the amount of any borrowings for investment purposes) in equity securities. Equity securities include common stocks, depositary receipts, equity interests in real estate investment trusts (REITs), and other securities that represent an ownership interest (or right to acquire an ownership interest) in a company or other issuer.

The Fund invests primarily in securities that Massachusetts Financial Services Company (d/b/a MFS Investment Management) ("MFS" or "Sub-Adviser") believes are income-producing equity securities. MFS invests the majority of the Fund's assets in dividend-paying common stocks, but may invest the Fund's assets in other types of income-producing securities, including convertible securities, preferred stocks, and equity interests in REITs, and may also invest the Fund's assets in non-income-producing equity securities.

The Sub-Adviser may invest the Fund's assets in foreign securities.

In selecting investments, MFS is not constrained by any particular investment style. MFS may invest the Fund's assets in the stocks of companies it believes to have above average earnings growth potential compared to other companies (growth companies), in the stocks of companies it believes are undervalued compared to their perceived worth (value companies), or in a combination of growth and value companies.

While MFS may invest the Fund's assets in securities of companies of any size, MFS primarily invests in securities of companies with large capitalizations.

MFS normally invests the Fund's assets across different industries and sectors, but MFS may invest a significant percentage of the Fund's assets in issuers in a single industry or sector.

MFS uses an active bottom-up approach to buying and selling investments for the Fund. Investments are selected primarily based on blending fundamental and quantitative research. MFS uses fundamental analysis of individual issuers to determine a fundamental rating for an issuer. MFS uses quantitative analysis to determine a quantitative rating for an issuer. MFS combines the fundamental rating with the quantitative rating to create a blended rating for an issuer. When the fundamental rating is not available, MFS treats the issuer as having a neutral fundamental rating. MFS then constructs the portfolio using a portfolio optimization process that considers the blended rating, as well as issuer, industry, and sector weightings, market capitalization, measures of expected volatility of the Fund's return (e.g., predicted beta and predicted tracking error), and other factors. MFS has the discretion to adjust the inputs and parameters used in the optimization process and the Fund's portfolio holdings based on factors such as the desired portfolio characteristics and MFS' qualitative assessment of the optimization results.

Principal Risks of Investing in the Fund. An investment in the Fund is not guaranteed. As with any mutual fund, the value of the Fund's shares will change, and you could lose money by investing in the Fund. The principal risks associated with investing in the Fund include:

· Market risk - Portfolio securities may decline in value due to factors affecting securities markets generally, such as real or perceived adverse economic, political, or regulatory conditions, inflation, changes in interest or currency rates or adverse investor sentiment, public health issues, including widespread disease and virus epidemics or pandemics, war, terrorism or natural disasters, among others. Adverse market conditions may be prolonged and may not have the same impact on all types of
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securities. The values of securities may fall due to factors affecting a particular issuer, industry or the securities market as a whole.

· Stock risk - Stock markets may experience significant short-term volatility and may fall sharply at times. Different stock markets may behave differently from each other and U.S. stock markets may move in the opposite direction from one or more foreign stock markets. The prices of individual stocks generally do not all move in the same direction at the same time and a variety of factors can affect the price of a particular company's stock.
· Equity securities risk - Common and preferred stocks represent equity ownership in a company. Stock markets are volatile, and equity securities generally have greater price volatility than fixed-income securities. The price of equity or equity-related securities will fluctuate and can decline and reduce the value of a portfolio investing in equity or equity-related securities. The value of equity or equity-related securities purchased or held by the Fund could decline if the financial condition of the companies the Fund invests in decline or if overall market and economic conditions deteriorate. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or an increase in production costs and competitive conditions within an industry. In addition, they may decline due to general market conditions that are not specifically related to a company or industry, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or generally adverse investor sentiment.
· Investment style risk - The returns from a certain investment style may be lower than the returns from the overall stock market. Growth stock prices frequently reflect projections of future earnings or revenues, and if earnings growth expectations are not met, their stock prices will likely fall, which may reduce the value of a Fund's investment in those stocks. Value stocks may not increase in price if other investors fail to recognize the company's value or the factors that are expected to increase the price of the security do not occur. Over market cycles, different investment styles may sometimes outperform other investment styles (for example, growth investing may outperform value investing).
· Dividend-paying stock risk - Dividend-paying stocks may underperform non-dividend paying stocks (and the stock market as a whole) over any period of time. The prices of dividend-paying stocks may decline as interest rates increase. In addition, issuers of dividend-paying stocks typically have discretion to defer or stop paying dividends. If the dividend-paying stocks held by an account reduce or stop paying dividends, the account's ability to generate income may be adversely affected.
· Large-capitalization investing risk - Large-capitalization stocks as a group could fall out of favor with the market, which may cause the Fund to underperform funds that focus on other types of stocks.
· Foreign securities risk - Investments in, or exposure to, foreign securities involve risks not typically associated with U.S. investments. These risks include, among others, adverse fluctuations in foreign currency values, possible imposition of foreign withholding or other taxes on income payable on the securities, as well as adverse political, social and economic developments, such as political upheaval, acts of terrorism, financial troubles, sanctions or the threat of new or modified sanctions, or natural disasters. Many foreign securities markets, especially those in emerging market countries, are less stable, smaller, less liquid, and less regulated than U.S. securities markets, and the costs of trading in those markets is often higher than in U.S. securities markets. There may also be less publicly available information about issuers of foreign securities compared to issuers of U.S. securities. In addition, the economies of certain foreign markets may not compare favorably with the economy of the United States with respect to issues such as growth of gross national product, reinvestment of capital, resources and balance of payments position.
· Managed portfolio risk - As an actively managed portfolio, the Fund's portfolio manager(s) make decisions to buy and sell holdings in the Fund's portfolio. Because of this, the value of the Fund's investments could decline because the financial condition of an issuer may change (due to such factors as management performance, reduced demand or overall market changes), financial markets may fluctuate or overall prices may decline, the Sub-Adviser's investment techniques could fail to achieve the Fund's investment objective or negatively affect the Fund's investment performance, or legislative, regulatory, or tax developments may affect the investment techniques available to the Sub-Adviser of the Fund. There is no guarantee that the investment objective of the Fund will be achieved.
· Investment strategy risk - The Sub-Adviser uses the principal investment strategies and other investment strategies to seek to achieve the Fund's investment objective. Investment decisions made by the Sub-Adviser in accordance with these investment strategies may not produce the returns the Sub-Adviser expected, and may cause the Fund's shares to decline in value or may cause the Fund to underperform other funds with similar investment objectives.
· REIT investment risk - The risks of investing in REITs include certain risks associated with the direct ownership of real estate and the real estate industry in general. These include risks related to general, regional and local economic conditions; difficulties in valuing and disposing of real estate; fluctuations in interest rates and property tax rates; shifts in zoning laws; environmental regulations and other governmental action; cash flow dependency; increased operating expenses; lack of availability of mortgage funds; losses due to natural disasters; overbuilding; losses due to casualty or condemnation; changes in property values and rental rates; the management skill and creditworthiness of the REIT manager; and other factors. REITs may have limited financial resources, may trade less frequently and in limited volume, may engage in dilutive offerings of securities and may be more volatile than other securities. REITs could be adversely affected by failure to maintain their exemptions from registration under the Investment Company Act of 1940, as amended, or failure to qualify for the "dividends paid deduction" under the Internal Revenue Code of 1986, as amended, which allows REITs to reduce their corporate taxable income for dividends paid to their shareholders.
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· Company risk - Investments in U.S. and/or foreign-traded equity securities may fluctuate more than the values of other types of securities in response to changes in a particular company's financial condition.
· Liquidity risk - Investments in securities that are difficult to purchase or sell (illiquid or thinly-traded securities) may reduce returns if the Fund is unable to sell the securities at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk arises, for example, from small average trading volumes, trading restrictions, or temporary suspensions of trading. To meet redemption requests, the Fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions.
· Redemption risk - Large redemption activity could result in the Fund being forced to sell portfolio securities at a loss or before the Adviser or Sub-Adviser would otherwise decide to do so. Large redemption activity in the Fund may also result in increased expense ratios, higher levels of realized capital gains or losses with respect to the Fund's portfolio securities, higher brokerage commissions, and other transaction costs.
· Quantitative strategy risk - Securities identified using quantitative analysis can perform differently from the market as a whole as a result of the factors used in the analysis, the weight placed on those factors, changes in a factor's historical trends, or for reasons included in the analysis. The factors used in quantitative analysis and the weights placed on those factors may not predict a security's value, and the effectiveness of the factors can change over time. These changes may not be reflected in the current quantitative model.
· Sector risk - Companies with similar characteristics may be grouped together in broad categories called sectors. Sector risk is the risk that securities of companies within specific sectors of the economy can perform differently than the overall market. For example, this may be due to changes in the regulatory or competitive environment or changes in investor perceptions regarding a sector. Because the Fund may allocate relatively more assets to certain sectors than others, the Fund's performance may be more susceptible to any developments which affect those sectors emphasized by the Fund. In addition, the Fund could underperform other funds investing in similar sectors or comparable benchmarks because of the investment manager's choice of securities within such sector.


Performance. The performance information shown provides some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns compared with those of a broad-based securities market index and an additional index that the Adviser believes more closely reflects the market segments in which the Fund invests. Performance prior to April 27, 2026 reflects the Fund's results when managed by the former Sub-Adviser, Invesco Advisers, Inc. The Fund's past performance is not necessarily an indication of how the Fund will perform in the future.

The returns shown in the bar chart and table do not include charges that will be imposed by variable insurance products. If these amounts were reflected, returns would be less than those shown.

Annual Total Returns as of December 31

Class A

Best Quarter (ended 12/31/2020): 13.86%; Worst Quarter (ended 3/31/2020): -23.81%

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Annual Total Returns as of December 31

Class I

Best Quarter (ended 12/31/2020): 13.94%; Worst Quarter (ended 3/31/2020): -23.81%

Average Annual Total Returns as of 12/31/2025
1 year 5 year Life of Fund (September 25, 2017)
JNL/MFS Equity Income Fund (Class A) 15.31 % 10.39 % 8.46 %
S&P 500 Index (reflects no deduction for fees, expenses, or taxes) 17.88 % 14.42 % 14.82 %
Morningstar US Large-Mid Cap Broad Value Index (reflects no deduction for fees, expenses, or taxes) 18.83 % 13.38 % 11.80 %
Average Annual Total Returns as of 12/31/2025
1 year 5 year Life of Class (September 25, 2017)
JNL/MFS Equity Income Fund (Class I) 15.64 % 10.72 % 8.79 %
S&P 500 Index (reflects no deduction for fees, expenses, or taxes) 17.88 % 14.42 % 14.82 %
Morningstar US Large-Mid Cap Broad Value Index (reflects no deduction for fees, expenses, or taxes) 18.83 % 13.38 % 11.80 %

Portfolio Management.

Investment Adviser to the Fund:
Jackson National Asset Management, LLC ("JNAM")

Sub-Adviser:
Massachusetts Financial Services Company (d/b/a MFS Investment Management) ("MFS")

Portfolio Managers:

Name: Joined Fund Management Team In: Title:
Jonathan Sage April 2026 Investment Officer, MFS
Nathan Bryant April 2026 Investment Officer, MFS
Jim Fallon April 2026 Investment Officer, MFS
Matt Krummell* April 2026 Investment Officer, MFS
Jed Stocks April 2026 Investment Officer, MFS
Jenney Zhang April 2026 Investment Officer, MFS

*Matt Krummell has announced his intention to retire effective April 7, 2027, and he will no longer be a portfolio manager of the Fund as of that date.

Purchase and Redemption of Fund Shares

Only separate accounts of Jackson National Life Insurance Company ("Jackson National") or Jackson National Life Insurance Company of New York ("Jackson National NY") and series, including fund of funds, of registered investment companies in which

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either or both of those insurance companies invest may purchase shares of the Fund. You may invest indirectly in the Fund through your purchase of a variable annuity or life insurance contract issued by a separate account of Jackson National or Jackson National NY that invests directly, or through a fund of funds, in this Fund. Any minimum initial or subsequent investment requirements and redemption procedures are governed by the applicable separate account through which you invest indirectly.

This Fund serves as an underlying investment by insurance companies, affiliated investment companies, and retirement plans for funding variable annuity and life insurance contracts and retirement plans.

Tax Information

The Fund expects to be treated as a partnership for U.S. federal income tax purposes, and does not expect to make regular distributions (other than in redemption of Fund shares) to shareholders, which generally are the participating insurance companies investing in the Fund through separate accounts of Jackson National or Jackson National NY and mutual funds owned directly or indirectly by such separate accounts. You should consult the prospectus of the appropriate separate account or description of the plan for a discussion of the U.S. federal income tax consequences to you of your contract, policy, or plan.

Payments to Broker-Dealers and Financial Intermediaries

If you invest in the Fund under a variable insurance contract or a plan that offers a variable insurance contract as a plan option through a broker-dealer or other financial intermediary (such as a financial institution), the Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's Website for more information.

JNL Series Trust published this content on April 27, 2026, and is solely responsible for the information contained herein. Distributed via EDGAR on April 27, 2026 at 13:21 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]