Westamerica Bank

April 13, 2004

For Immediate Release


San Rafael, CA: Westamerica Bancorporation (NASDAQ: WABC), parent company of Westamerica Bank, today reported record quarterly net income for the first quarter of 2004 of $24.3 million or $.74 diluted earnings per share, up from $23.0 million or $.69 diluted earnings per share for the first quarter of 2003. The return on equity (ROE) for the first quarter of 2004 was 30.5 percent, and the return on assets (ROA) was 2.20 percent, compared to 29.6 percent and 2.22 percent, respectively, in the first quarter of 2003.

"We are pleased with first quarter results, especially the stabilization of our net interest margin compared to the fourth quarter of 2003, stable loan volume and controlled expenses. Our 5.27 percent margin and 38.2 percent efficiency ratio helped deliver our record earnings level. Annualized net loan losses to average loans were 0.15 percent, unchanged from full-year 2003 levels," said Chairman, President and CEO David Payne. "Westamerica's return on equity and return on assets remain at high levels relative to the banking industry," added Payne.

Net interest income on a fully taxable equivalent basis was $54.6 million in the first quarter of 2004, compared to $54.8 million in the prior quarter and to $54.1 million in the first quarter of 2003. The first quarter 2004 net interest margin on a fully taxable equivalent basis was 5.27 percent, up one basis point from 5.26 percent in the prior quarter and compared to 5.58 percent for the first quarter of 2003.

The provision for loan losses was $750 thousand for the first quarter of 2004 unchanged from the previous quarter and down from $900 thousand for the first quarter of 2003. Net loan losses totaled $825 thousand or 0.15 percent of average loans (annualized) in the first quarter of 2004.

Noninterest income in the first quarter of 2004 totaled $10.9 million, up $374 thousand from the previous quarter, and up $491 thousand from the first quarter of 2003. The increase in the first quarter of 2004 from the previous quarter included higher gains on sale of OREO and service charges on deposit accounts, offset in part by lower financial services commissions and merchant credit card income. The increase in the first quarter 2004 from the first quarter 2003 included higher gains on sale of OREO, service charges on deposit accounts and debit card fees, offset in part by lower mortgage banking income. First quarter 2004 noninterest income includes securities gains totaling $1.8 million and losses on extinguishment of FHLB advances totaling $1.8 million.

Noninterest expense for the first quarter of 2004 totaled $25.0 million, down $166 thousand from the previous quarter, and down $543 thousand from the first quarter of 2003. The reduction in the first quarter of 2004 from the previous quarter included lower occupancy and equipment, professional fees, and loan related expenses, offset in part by higher employee benefits and merchant card expense. The reduction in the first quarter of 2004 from the first quarter of 2003 included lower salaries, occupancy and equipment, amortization of core deposit intangibles, and merchant card expense, offset in part by higher telephone expenses and operational losses. The efficiency ratio for first quarter 2004 was 38.2 percent compared with 38.6 percent in the prior quarter and 39.6 percent in the first quarter of 2003.

Shareholders' equity was $339 million at March 31, 2004, essentially unchanged from $337 million at March 31, 2003. The Company's equity-to-asset ratio was 7.7 percent at March 31, 2004, compared to 7.7 percent at March 31, 2003. Net repurchases of the Company's common stock in the first quarter 2004 totaled approximately 500 thousand shares.

At March 31, 2004, the Company had total assets of $4.4 billion, up one percent from March 31, 2003. At March 31, 2004, total loans outstanding were $2.3 billion, essentially unchanged from December 31, 2003.

Westamerica Bancorporation, through its wholly owned subsidiary Westamerica Bank, operates 87 branches and two trust offices throughout 22 Northern and Central California counties.

Quarterly Financial Highlights

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 annual and quarterly reports filed with the Securities and Exchange Commission, including the Company’s Form 10-K for the year ended December 31, 2003, describe some of these factors, including certain credit, market, operational, liquidity and interest rate 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 Sarbanes-Oxley Act of 2002 and the Gramm-Leach-Bliley Act of 1999, the combination of the former Kerman State Bank, and other 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.

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