THE CORPORATE LIBRARY

Related Party Transactions and Outside Related Director Information

Westamerica Bancorporation (WABC)

3/20/2006 Proxy Information

Mr. Bowler retired in 2002 as Senior Vice President and Treasurer of Westamerica Bancorporation.

Certain of the directors, executive officers and their associates have had banking transactions with subsidiaries of the Corporation in the ordinary course of business. With the exception of the CorporationÕs Employee Loan Program, all outstanding loans and commitments included in such transactions were made on substantially the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with other persons, did not involve more than a normal risk of collectibility, and did not present other favorable features. As part of the Employee Loan Program, all employees, including corporate officers, are eligible to receive mortgage loans at one percent (1%) below Westamerica BankÕs prevailing interest rate at the time of loan origination. All loans to corporate officers under the Employee Loan Program are made by Westamerica Bank in compliance with the applicable restrictions of section 22(h) of the Federal Reserve Act.

3/23/2005 Proxy Information

Certain of the directors, executive officers and their associates have had banking transactions with subsidiaries of the Corporation in the ordinary course of business. With the exception of the CorporationÕs Employee Loan Program, all outstanding loans and commitments included in such 3/23/2005transactions were made on substantially the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with other persons, did not involve more than a normal risk of collectibility and did not present other favorable features. As part of the Employee Loan Program, all employees, including corporate officers, are eligible to receive mortgage loans at one percent (1%) below Westamerica BankÕs prevailing interest rate at the time of loan origination. All loans to corporate officers under the Employee Loan Program are made by Westamerica Bank in compliance with the applicable restrictions of section 22(h) of the Federal Reserve Act.

3/17/2004 Proxy Information

E. Joseph Bowler retired in 2002 as Senior Vice President and Treasurer of Westamerica Bancorporation.

Certain of the directors, executive officers and their associates have had banking transactions with subsidiaries of the Corporation in the ordinary course of business. With the exception of the CorporationÕs Employee Loan Program, all outstanding loans and commitments included in such transactions were made on substantially the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with other persons, did not involve more than a normal risk of collectibility and did not present other favorable features. As part of the Employee Loan Program, all employees, including corporate officers, are eligible to receive mortgage loans at one percent (1%) below the BankÕs prevailing interest rate at the time of loan origination.

3/17/2003 Proxy Information

Certain of the directors, executive officers and their associates have had banking transactions with subsidiaries of the Corporation in the ordinary course of business. With the exception of the CorporationÕs Employee Loan Program, all outstanding loans and commitments included in such transactions were made on substantially the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with other persons, did not involve more than a normal risk of collectibility and did not present other unfavorable features. As part of the Employee Loan Program, all employees, corporate officers and directors are eligible to receive mortgage loans at one percent (1%) below the bankÕs prevailing interest rate.