Westamerica Bank

September 14, 2005

For Immediate Release


San Rafael, CA: Westamerica Bancorporation (NASDAQ: WABC), is scheduled to participate in the RBC Capital Markets 2005 Financial Institutions Conference.

David Payne, Chairman, President and CEO, will make a presentation beginning at 9:30 a.m. ET on Tuesday, September 20. Investors and the public can access the presentation via a webcast at:

http://www.wsw.com /webcast/rbc33/wabc and follow the links to the webcast.

The following is the slide presentation as shown for the RBC Capital Markets Financial Institutions Conference:

01/30 

   

Westamerica Bancorporation through its wholly owned subsidiary, Westamerica Bank, operates 88 branches and two trust offices throughout 21 Northern and Central California counties.

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