X0508 4 2024-01-25 0000311094 WESTAMERICA BANCORPORATION WABC 0001201513 PAYNE DAVID L WESTAMERICA BANCORPORATION 4550 MANGELS BLVD. FAIRFIELD CA 94534 1 1 Chairman, President & CEO 0 Common Stock 2024-01-25 4 S 0 15000 49.7527 D 288689 I By Trust Common Stock 991 D Common Stock 528837 I By Gibson Radio & Publishing Company Common Stock 462 I By Son Common Stock 345808 I By Trust Common Stock 10924.913 I Esop The reporting person and members of his immediate family are among the beneficiaries of the trust. The reporting person disclaims beneficial ownership of the shares held by the trust except to the extent of his pecuniary interest therein. The reporting person is President and CEO of Gibson Radio and Publishing Company and disclaims beneficial ownership of 528,837 shares. /s/ David L. Payne 2024-01-26