Prospectus by Investment Company (Form 497)

Supplement Dated July 23, 2025

To The Prospectus Dated April 28, 2025

JNL^® Series Trust

Please note that the changes below may impact your variable annuity and/or variable life product(s).

All changes are effective July 21, 2025.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/American Funds Bond Fund of America Fund, JNL/American Funds Capital Income Builder Fund, JNL/American Funds Capital World Bond Fund, JNL/American Funds Global Growth Fund, JNL/American Funds Global Small Capitalization Fund, JNL/American Funds Growth Fund, JNL/American Funds Growth-Income Fund, JNL/American Funds International Fund, JNL/American Funds New World Fund, JNL/American Funds^® Washington Mutual Investors Fund, JNL/American Funds Moderate Allocation Fund, JNL/American Funds Growth Allocation Fund, JNL/American Funds Moderate Growth Allocation Fund, JNL Multi-Manager Emerging Markets Equity Fund, JNL Multi-Manager International Small Cap Fund, JNL Multi-Manager Mid Cap Fund, JNL Multi-Manager Small Cap Growth Fund, JNL Multi-Manager Small Cap Value Fund, JNL Multi-Manager U.S. Select Equity Fund, JNL Moderate ETF Allocation Fund, JNL Moderate Growth ETF Allocation Fund, JNL Growth ETF Allocation Fund, JNL/AB Sustainable Global Thematic Fund, JNL/AQR Large Cap Defensive Style Fund, JNL/BlackRock Global Allocation Fund, JNL/BlackRock Global Natural Resources Fund, JNL/BlackRock Large Cap Select Growth Fund, JNL/Causeway International Value Select Fund, JNL/ClearBridge Large Cap Growth Fund, JNL/Cohen & Steers U.S. Realty Fund, JNL/DoubleLine^® Emerging Markets Fixed Income Fund, JNL/DoubleLine^® Shiller Enhanced CAPE Fund, JNL/DoubleLine^® Total Return Fund, JNL/Dreyfus Government Money Market Fund, JNL/Fidelity Institutional Asset Management^® Total Bond Fund, JNL/First Sentier Global Infrastructure Fund, JNL/Franklin Templeton Income Fund, JNL/GQG Emerging Markets Equity Fund, JNL/Goldman Sachs 4 Fund, JNL/Invesco Diversified Dividend Fund, JNL/Invesco Global Growth Fund, JNL/Invesco Small Cap Growth Fund, JNL/JPMorgan Global Allocation Fund, JNL/JPMorgan Hedged Equity Fund, JNL/JPMorgan MidCap Growth Fund, JNL/JPMorgan Nasdaq^® Hedged Equity Fund, JNL/JPMorgan U.S. Government & Quality Bond Fund, JNL/Loomis Sayles Global Growth Fund, JNL/Lord Abbett Short Duration Income Fund, JNL/MFS Mid Cap Value Fund, JNL/Mellon Bond Index Fund, JNL/Mellon U.S. Stock Market Index Fund, JNL/Mellon Dow^SM Index Fund, JNL/Mellon Emerging Markets Index Fund, JNL/Mellon International Index Fund, JNL/Mellon Nasdaq^® 100 Index Fund, JNL/Mellon World Index Fund, JNL/Mellon Real Estate Sector Fund, JNL/Morningstar SMID Moat Focused Index Fund, JNL/Morningstar U.S. Sustainability Index Fund, JNL/Morningstar Wide Moat Index Fund, JNL/Neuberger Berman Commodity Strategy Fund, JNL/Neuberger Berman Gold Plus Strategy Fund, JNL/Neuberger Berman Strategic Income Fund, JNL/Newton Equity Income Fund, JNL/PIMCO Income Fund, JNL/PIMCO Investment Grade Credit Bond Fund, JNL/PIMCO Real Return Fund, JNL/PPM America Investment Grade Credit Fund, JNL/PPM America Total Return Fund, JNL/RAFI^® Multi-Factor U.S. Equity Fund, JNL/RAFI^® Fundamental U.S. Small Cap Fund, JNL/T. Rowe Price Balanced Fund, JNL/T. Rowe Price Capital Appreciation Fund, JNL/T. Rowe Price Capital Appreciation Equity Fund, JNL/T. Rowe Price U.S. High Yield Fund, JNL/Vanguard Moderate ETF Allocation Fund, JNL/Vanguard Moderate Growth ETF Allocation Fund, JNL/Vanguard Growth ETF Allocation Fund, JNL/WMC Equity Income Fund, JNL/WMC Global Real Estate Fund, JNL/JPMorgan Managed Aggressive Growth Fund, JNL/JPMorgan Managed Conservative Fund, JNL/JPMorgan Managed Growth Fund, JNL/JPMorgan Managed Moderate Fund, JNL/JPMorgan Managed Moderate Growth Fund, JNL Conservative Allocation Fund, JNL Moderate Allocation Fund, JNL Moderate Growth Allocation Fund, JNL Growth Allocation Fund, JNL Aggressive Growth Allocation Fund, JNL Bond Index Fund, and JNL Emerging Markets Index Fund, please delete the first paragraph in the entirety and replace with the following:

Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks). To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments. There may be additional risks that may affect the Fund's ability to achieve its stated investment objective. These additional risks are:

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/American Funds Balanced Fund, JNL/DoubleLine^® Core Fixed Income Fund, JNL/JPMorgan U.S. Value Fund, JNL/Lazard International Quality Growth Fund, JNL/Mellon S&P 500 Index Fund, JNL/Mellon S&P 400 MidCap Index Fund, JNL/Mellon Small Cap Index Fund, JNL/Mellon Dow^SM Index Fund, JNL S&P 500 Index Fund, JNL/Morningstar PitchBook Listed Private Equity Index Fund, JNL/T. Rowe Price Short-Term Bond Fund, JNL/Westchester Capital Event Driven Fund, JNL/WMC Balanced Fund, JNL/WMC Value Fund, JNL International Index Fund, JNL Mid Cap Index Fund, and JNL Small Cap Index Fund, after the first paragraph, please add the following:

To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/Mellon Communication Services Sector Fund, JNL/Mellon Consumer Discretionary Sector Fund, JNL/Mellon Energy Sector Fund, JNL/Mellon Healthcare Sector Fund, JNL/Mellon Information Technology Sector Fund and JNL/Mellon Utilities Sector Fund, please delete the second paragraph in the entirety and replace with the following:

To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/Mellon Consumer Staples Sector Fund, please delete the first paragraph in the entirety and replace with the following:

Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks). General risks of consumer staples companies include currency fluctuations, increased competition, increased governmental regulation, accommodative monetary policy and stimulative fiscal policy. Generally, spending on consumer staples is affected by the economic health of consumers. Improving global economic growth may adversely affect consumer staples companies. To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest to some degree in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/Mellon Financial Services Sector Fund, please delete the fifth paragraph in the entirety and replace with the following:

To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/Mellon Industrials Sector Fund, please delete the first paragraph in the entirety and replace with the following:

Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks). The industrial sector is characterized by a variety of markets, with companies spanning the quality spectrum in terms of competitive advantage, growth prospects, and exposure to economic cycles. General risks of industrial companies include high cyclicality, fiscal austerity measures, and a stronger U.S. dollar, which may adversely affect exports and U.S. industrial company profitability. To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest to some degree in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/Mellon Materials Sector Fund, please delete the first paragraph in the entirety and replace with the following:

Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks). Commodity prices are a key determinant of materials companies' earnings. General risks of materials companies include high cyclicality, reduction in demand for processes commodities, increased labor costs, and a stronger U.S. dollar, which may adversely affect exports and U.S. materials company profitability. To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest to some degree in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL Multi-Manager Alternative Fund, JNL Multi-Manager Floating Rate Income Fund, JNL/DFA International Core Equity Fund, JNL/DFA U.S. Core Equity Fund, JNL/T. Rowe Price Growth Stock Fund, JNL/T. Rowe Price Mid-Cap Growth Fund, and JNL/T. Rowe Price Value Fund, after the second paragraph, please add the following:

To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," JNL/PPM America High Yield Bond Fund, after the third paragraph, please add the following:

To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/WCM China Quality Growth Fund and JNL/WCM Focused International Equity Fund, after the fifth paragraph, please add the following:

To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/William Blair International Leaders Fund, after the sixth paragraph please add the following:

To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments.

In the section "Additional Information About Each Fund," under "Additional Information About the Other Investment Strategies, Other Investments and Risks of the Fund (Other than Principal Strategies/Risks)," for the JNL/DFA U.S. Small Cap Fund, after the nineth paragraph, please add the following:

To effectively manage cash inflows and outflows, the Fund may maintain a cash position primarily consisting of shares of money market mutual funds including the affiliated JNL Government Money Market Fund and investments in other investment companies (such as exchange traded funds) to the extent permitted under the 1940 Act. The Fund may also invest in money market instruments.

This Supplement is dated July 23, 2025.