Westamerica Bank

June 13, 2005

For Immediate Release


San Rafael, CA: On June 10, 2005, Westamerica Bancorporation (NASDAQ: WABC) completed the sale of one of its two branch offices located in Lakeport, California. The branch sale was required by the Board of Governors of the Federal Reserve System as a condition to approving Westamerica's acquisition of Redwood Empire Bancorp, which was completed March 1, 2005. The deposits sold in the branch transaction represented approximately one percent of Westamerica's total deposits of $3.9 billion at March 31, 2005.

Following completion of this transaction, Westamerica Bancorporation, through its wholly owned subsidiary Westamerica Bank, operates 89 branches and two trust offices throughout 22 Northern and Central California counties. At March 31, 2005, Westamerica's assets totaled approximately $5.2 billion.