0000933691 2026-09-30 2026-09-30 0000933691 jnlst:S000048717Member 2026-09-30 2026-09-30 0000933691 jnlst:S000048717Member jnlst:ManagedPortfolioRiskMember 2026-09-30 2026-09-30 0000933691 jnlst:S000048717Member jnlst:REITInvestmentRiskMember 2026-09-30 2026-09-30 0000933691 jnlst:S000052995Member 2026-09-30 2026-09-30 false JNL SERIES TRUST 497 N-1A 0000933691 2026-09-30 2026-04-27 In the section, “Summary Overview of Each Fund,” under “Principal Investment Strategies,” for the JNL Multi-Manager Alternative Fund, after the sixth paragraph, please add the following: The Fund may invest in a variety of equity securities, including common stock, preferred stock, rights and warrants to purchase common stock, depositary receipts, securities convertible into common and preferred stock and non-convertible preferred stock. Additionally, from time to time, the Fund may invest in shares of companies through initial public offerings (“IPOs”). In the section, “Summary Overview of Each Fund,” under “Principal Investment Strategies,” subsection “Equity Long/Short Strategies” for the JNL Multi-Manager Alternative Fund, please delete the second paragraph in the entirety and replace with the following: Boston Partners Global Investors, Inc. (“Boston Partners”) invests in long positions in stocks it identifies as being undervalued and takes short positions in stocks that it has identified as overvalued. The cash proceeds from short sales will be invested in short-term cash instruments to produce a return on such proceeds just below the federal funds rate. Boston Partners invests, both long and short, in securities principally traded in the United States markets. The strategy’s long and short positions may involve (without limit) equity securities of foreign issuers that are traded in the United States markets. The strategy may also invest a portion of its assets directly in equity securities of foreign issuers. Boston Partners may invest in securities of companies operating for three years or less (“unseasoned issuers”). Boston Partners will determine the size of each long or short position by analyzing the tradeoff between the attractiveness of each position and its impact on the risk of the overall portfolio. Boston Partners seeks to construct a portfolio that has less volatility than the United States equity market generally. Boston Partners examines various factors in determining the value characteristics of such issuers including price-to-book value ratios and price-to-earnings ratios. These value characteristics are examined in the context of the issuer’s operating and financial fundamentals such as return on equity, earnings growth and cash flow. Boston Partners selects securities based on a continuous study of trends in industries and companies, earnings power and growth and other investment criteria. <table cellpadding="0" cellspacing="0" style="font: 10pt Courier New, Courier, Monospace; width: 100%; margin-top: 12pt; margin-bottom: 0pt"><tr style="vertical-align: top"> <td style="width: 5%">·</td><td style="width: 95%">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.</td></tr></table> <table cellpadding="0" cellspacing="0" style="font: 10pt Courier New, Courier, Monospace; width: 100%; margin-top: 12pt; margin-bottom: 0pt"><tr style="vertical-align: top"> <td style="width: 5%">·</td><td style="width: 95%">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.</td></tr></table> In the section, “Summary Overview of Each Fund,” under “Principal Investment Strategies,” for the JNL/DoubleLine® Emerging Market Fixed Income Fund, please delete the seventh paragraph in the entirety and replace with the following: The Fund may invest in investments denominated in any currency, but expects to invest approximately 50% of its assets in investments denominated in the U.S. dollar and approximately 50% of its assets in investments denominated in local currencies.