X0508 4/A 2025-05-20 2025-11-04 0 0001516912 Origin Bancorp, Inc. OBK 0002040255 Jones Cecil W. 500 SOUTH SERVICE ROAD EAST RUSTON LA 71270 1 0 0 0 0 Common Stock 2025-05-20 4 L 0 16 36.46 A 12725 D Common Stock 2025-11-04 4 L 0 17 36.39 A 12742 D Common Stock 2026-02-24 4 L 0 43 36.52 A 12785 D Represents shares that were purchased as part of a dividend reinvestment program. This transaction was executed in multiple trades at prices ranging from $34.59 to $38.53. The price reported above reflects the weighted average daily purchase price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. This transaction was executed in multiple trades at prices ranging from $34.12 to $38.98. The price reported above reflects the weighted average daily purchase price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. /s/ Drake Mills, as Attorney-in-Fact 2026-02-24