Putnam Mortgage Securities Fund

10/31/2025 | Press release | Distributed by Public on 10/31/2025 07:37

Summary Prospectus by Investment Company (Form 497K)

PGOF-P41

SUPPLEMENT DATED OCTOBER 31, 2025

TO THE SUMMARY PROSPECTUS, PROSPECTUS

AND STATEMENT OF ADDITIONAL INFORMATION ("SAI")

OF EACH FUND LISTED IN SCHEDULE A

Effective October 31, 2025, the following changes are made to each fund's Summary Prospectus, Prospectus and SAI:

a)

The following footnote is added to all references to Paul Varunok in each fund's Summary Prospectus, Prospectus and SAI:

* Mr. Varunok is anticipated to step down as a member of the fund's portfolio management team on or about December 31, 2025. Thereafter, he will transition to an advisory role with Franklin Templeton.

Schedule A

Putnam Mortgage Securities Fund

Putnam Mortgage Opportunities Fund

Putnam VT Mortgage Securities Fund

Shareholders should retain this Supplement for future reference.

Putnam Mortgage Securities Fund published this content on October 31, 2025, and is solely responsible for the information contained herein. Distributed via Edgar on October 31, 2025 at 13:37 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 If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]