144 0001136856 XXXXXXXX LIVE 0001068851 PROSPERITY BANCSHARES INC 001-35388 4295 SAN FELIPE N/A HOUSTON TX 77027 7136939300 HOLMES NED S Director Common UBS Financial Services, Inc.

11 Madison Avenue 4th Floor New York NY 10010

15400 1089088.00 100854689 06/10/2026 NYSE Common 05/31/2002 Restricted Stock Issuer N 7000 05/31/2002 N/A Common 05/22/2001 Restricted Stock Issuer N 7000 05/22/2001 N/A Common 12/17/2002 Restricted Stock Issuer N 1400 12/17/2002 N/A N Ned S Holmes

4295 SAN FELIPE HOUSTON TX 77027

Common 03/11/2026 6500 442042.70 Ned S Holmes Profit Sharing Plan

4295 SAN FELIPE HOUSTON TX 77027

Common 03/11/2026 6500 442036.70 The Sherrill S Holmes Child's Trust FBO Allison Holmes

4295 SAN FELIPE HOUSTON TX 77027

Common 03/11/2026 1300 88383.22 7,000 shares represented in this filing are being sold under Ned S Holmes. 7,000 shares represented in this filing are being sold under Ned S Holmes Profit Sharing Plan. 1,400 shares represented in this filing are being sold under The Sherrill S Holmes Child's Trust FBO Allison Holmes. Between 3/11/2026 and 6/9/2026 6,500 shares were sold by Ned S. Holmes resulting gross proceeds of $442,042.70; 6,500 shares were sold by Ned S. Holmes Profit Sharing Plan resulting in gross proceeds of $442,036.70 and 1,300 shares were sold by The Sherrill S Holmes Child's Trust FBO Allison Holmes resulting in gross proceeds of $88,383.22. Itemized details are provided in the attached Exhibit. 06/10/2026 07/30/2024 /s/ UBS Financial Services Inc, as attorney-in-fact for Ned S Holmes