MML SERIES INVESTMENT FUND
MML VIP Invesco Main Street Equity Fund
Supplement dated October 6, 2026 to the
Prospectus dated April 24, 2026 and the
Summary Prospectus dated April 24, 2026
This supplement provides new and additional information beyond that contained in the Prospectus and Summary Prospectus, and any previous supplements. It should be retained and read in conjunction with the Prospectus and Summary Prospectus, and any previous supplements.
Effective immediately, the information for Benjamin Ram found (on page 59 of the Prospectus) under the heading Portfolio Manager(s) in the section titled Management and on page 121 of the Prospectus under the heading Subadvisers and Portfolio Managers in the section titled Management of the Funds, is hereby removed.
Effective immediately, the following information supplements the information found (on page 59 of the Prospectus) under the heading Portfolio Manager(s) in the section titled Management:
Magnus Krantz is a Portfolio Manager at Invesco Advisers. He has managed the Fund since September 2026.
Effective immediately, the following information supplements the information for Invesco Advisers, Inc. beginning on page 120 of the Prospectus under the heading Subadvisers and Portfolio Managers in the section titled Management of the Funds:
Magnus Krantz 

is a portfolio manager of the MML VIP Invesco Main Street Equity Fund. Mr. Krantz is a Portfolio Manager at Invesco Advisers. He has been associated with Invesco Advisers and/or its affiliates since 2019. Prior to 2019, he was a Vice President of OppenheimerFunds, Inc. (“OFI”) since May 2009 and a portfolio manager of OFI since November 2012. He has served as sector manager for technology for OFI’s Main Street Investment Team since May 2009. Prior to joining OFI, Mr. Krantz was a sector manager at RS Investments and Guardian Life Insurance Company. Mr. Krantz joined Guardian Life Insurance Company in December 2005 and transitioned to RS Investments in October 2006 in connection with Guardian Life Insurance Company’s acquisition of an interest in RS Investments.
PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE
MMLPRO-26-06
VIPMSE-26-01
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
MML SERIES INVESTMENT FUND
MML VIP Invesco Main Street Equity Fund
Supplement dated October 6, 2026 to the
Statement of Additional Information dated April 24, 2026
This supplement provides new and additional information beyond that contained in the Statement of Additional Information (“SAI”) and any previous supplements. It should be retained and read in conjunction with the SAI and any previous supplements.
Effective immediately, the following information replaces similar information for the MML VIP Invesco Main Street Equity Fund (the “Fund”) found under Invesco Advisers, Inc. on page B-236 in the section titled Appendix C — Additional Portfolio Manager Information: 
The portfolio managers of the Main Street Equity Fund are Manind Govil and Magnus Krantz.
Effective immediately, the following information supplements the information for the Fund found on page B-236 under the headings Other Accounts Managed and Ownership of Securities in the section titled Appendix C — Additional Portfolio Manager Information:
Other Accounts Managed:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Number of
Accounts
Managed*
 
 
Total
Assets*
 
 
Number of Accounts
Managed for
which Advisory Fee is
Performance-Based*
 
 
Total
Assets*
Magnus Krantz
 
 
 
 
 
 
 
 
 
 
 
 
Registered investment companies  **
 
 
10
 
 
$13,970.7 million
 
 
0
 
 
$0
Other pooled investment vehicles
 
 
1
 
 
$55.9 million
 
 
0
 
 
$0
Other accounts
 
 
300 * * *
 
 
$122.0 million
 
 
0
 
 
$0
 
 
 
 
 
 
 
 
 
 
 
 
 
*
The information provided is as of June 30, 2026.
**
Does not include the Main Street Equity Fund.
***
These are accounts of individual investors for which Invesco Advisers provides investment advice. Invesco Advisers offers separately managed accounts that are managed according to the investment models developed by its portfolio managers and used in connection with the management of certain Invesco Funds. These accounts may be invested in accordance with one or more of those investment models and investments held in those accounts are traded in accordance with the applicable models.
Ownership of Securities:
As of June 30, 2026, Mr. Krantz did not own any shares of the Main Street Equity Fund.
Effective immediately, the information for Benjamin Ram found on page B-236 relating to the Fund in the section titled Appendix C — Additional Portfolio Manager Information is hereby removed.
PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE
MMLSAI-26-04