Westamerica to Participate in Keefe, Bruyette & Woods 2013 Boston Bank Conference

Westamerica to Participate in Keefe, Bruyette & Woods 2013 Boston Bank
Conference

SAN RAFAEL, Calif., Feb. 21, 2013 (GLOBE NEWSWIRE) -- Westamerica
Bancorporation (Nasdaq:WABC) is scheduled to participate in the Keefe,
Bruyette & Woods 2013 Boston Bank Conference.

David Payne, President, Chairman, and CEO, will make a presentation beginning
at 8:45 a.m. ET on Wednesday, February 27, 2013. Investors and the public can
access the presentation via a webcast at http://www.wsw.com/webcast/kbw9.

Westamerica Bancorporation, through its wholly owned subsidiary, Westamerica
Bank, operates banking and trust offices throughout Northern and Central
California.

The Westamerica Bancorporation logo is available at
http://www.globenewswire.com/newsroom/prs/?pkgid=3638

        Westamerica Bancorporation Web Address: www.westamerica.com

FORWARD-LOOKING INFORMATION:

The following appears in accordance with the Private Securities Litigation
Reform Act of 1995:

This press release may contain forward-looking statements about the Company,
including descriptions of plans or objectives of its management for future
operations, products or services, and forecasts of its revenues, earnings or
other measures of economic performance. Forward-looking statements can be
identified by the fact that they do not relate strictly to historical or
current facts. They often include the words "believe," "expect," "anticipate,"
"intend," "plan," "estimate," or words of similar meaning, or future or
conditional verbs such as "will," "would," "should," "could," or "may."

Forward-looking statements, by their nature, are subject to risks and
uncertainties. A number of factors — many of which are beyond the Company's
control — could cause actual conditions, events or results to differ
significantly from those described in the forward-looking statements. The
Company's most recent reports filed with the Securities and Exchange
Commission, including the annual report for the year ended December 31, 2011
filed on Form 10-K and quarterly report for the quarter ended September 30,
2012 filed on Form 10-Q, describe some of these factors, including certain
credit, interest rate, operational, liquidity and market risks associated with
the Company's business and operations. Other factors described in these
reports include changes in business and economic conditions, competition,
fiscal and monetary policies, disintermediation, legislation including the
Dodd-Frank Wall Street Reform and Consumer Protection Act of 2011, the
Sarbanes-Oxley Act of 2002 and the Gramm-Leach-Bliley Act of 1999, and mergers
and acquisitions.

Forward-looking statements speak only as of the date they are made. The
Company does not undertake to update forward-looking statements to reflect
circumstances or events that occur after the date forward looking statements
are made.

CONTACT: Westamerica Bancorporation
         Robert A. Thorson - SVP & Chief Financial Officer
         707-863-6840

Westamerica Bancorporation Logo