SCHEDULE 13D/A 0001015402-04-001741 0001241883 XXXXXXXX LIVE 10 Common Stock, no par value 12/02/2025 false 0000036146 898402102 TRUSTMARK CORP

248 East Capitol Street P.O. Box 291 Jackson MS 39201

Matthew L. Holleman, III, (601) 366-8363 Trustee Robert M. Hearin Support Foundation P. O. Box 16505 Jackson MS 39236-6505 0001241883 ROBERT M HEARIN SUPPORT FOUNDATION a OO MS 2735000 0 2735000 0 2735000 N 4.57 OO Y The Robert M Hearin Foundation a OO MS 240000 0 240000 0 240000 N 0.4 OO Common Stock, no par value TRUSTMARK CORP 248 East Capitol Street P.O. Box 291 Jackson MS 39201 This Amendment No. 10 (this "Amendment") amends and supplements the Statement on Schedule 13D, as heretofore amended (the "Schedule 13D"), relating to the shares of common stock, no par value (the "Shares"), of Trustmark Corporation, a Mississippi corporation (the "Issuer"), previously filed by Robert M. Hearin Support Foundation, The Robert M. Hearin Foundation, Capitol Street Corporation (currently, Capitol Street LLC, pursuant to a merger) and Galaxie Corporation (each a "Reporting Person" and, collectively, the "Reporting Persons"). This Amendment is being filed to update the Schedule 13D in light of the change in the Reporting Persons' ownership percentage of the Shares caused (i) by the sale of an aggregate of 615,000 Shares by Robert M. Hearin Support Foundation on December 2, 2025, (ii) and by other sales of Shares beneficially owned by Reporting Persons, since the previous amendment, which such other sales did not collectively result in a disposition of 1% of the outstanding shares of the Issuer. This Amendment is also being filed to update Item 5. Since the previous amendment, Capitol Street has sold all of its Trustmark Shares, and Galaxie's ownership interest was limited to shared voting and disposition authority over Capitol Street's shares. As a result of those sales, both entities have been removed from this Amendment. Based on the sale of 615,000 shares by the Robert M. Hearin Support Foundation on December 2, 2025, the Robert M. Hearin Support Foundation and The Robert M. Hearin Foundation cease to hold more than 5% of the outstanding stock of the Issuer. Therefore, this Amendment is the final amendment to the Schedule 13D and constitutes an exit filing for Robert M. Hearin Support Foundation and The Robert M. Hearin Foundation. No change. No change. No change. Item 5 is hereby amended and supplemented to add the information incorporated by reference in Exhibit 99.1 of this Amendment The beneficial ownership information of the Reporting Persons is hereby incorporated by reference in Exhibit 99.1 of this Amendment. Except as disclosed herein, there have been no transactions by persons listed in Item 2 in the class of securities reported on that were effected during the past sixty days. No other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities. The Reporting Persons have ceased to be the beneficial owner of more than 5% of the outstanding stock of the Issuer. No change. Exhibit 99.1 - Changes to Item 5 Exhibit 99.2 - Schedule I ROBERT M HEARIN SUPPORT FOUNDATION /s/ Robert M. Hearin, Jr. 12/03/2025 /s/ Matthew L. Holleman, III 12/03/2025 /s/ Steve M. Hendrix 12/03/2025 /s/ Laurie Hearin McRee 12/03/2025 /s/ Alan W. Perry 12/03/2025 /s/ Jackie Blackwell 12/03/2025 /s/ Phillip Sykes 12/03/2025 The Robert M Hearin Foundation /s/ Robert M. Hearin, Jr. 12/03/2025 /s/ Matthew L. Holleman, III 12/03/2025 /s/ Steve M. Hendrix 12/03/2025 /s/ Laurie Hearin McRee 12/03/2025 /s/ Alan W. Perry 12/03/2025 /s/ Jackie Blackwell 12/03/2025 /s/ Phillip Sykes 12/03/2025