UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): March 13, 2018

Westamerica Bancorporation

(Exact name of registrant as specified in its charter)

California	001-09383	94-2156203
(State or other jurisdiction of incorporation)	(Commission File No.)	(IRS Employer Identification Number)
1108 Fifth Avenue San Rafael, California		94901
(Address of principal executive offices)		(Zip Code)

Registrant’s telephone number, including area code: (707) 863-6000

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

 Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). Emerging growth company ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the exchange Act. ¨

Section 5 – Corporate Governance and Management

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

(b) Departure of Member of Board of Directors

Effective March 8, 2018, Arthur C. Latno, Jr., retired from Westamerica Bancorporation’s (the Company) Board of Directors. Mr. Latno served as a member of the Executive Committee, the Employee Benefits and Compensation Committee, the Loan and Investment Committee, as Chairman of the Nominating Committee, and as a member of Westamerica Bank Board of Directors. He served on the Company’s Board since 1985. Mr. Latno did not advise the Company of any disagreement with the Company on any matter relating to its operations, policies or practices.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	WESTAMERICA BANCORPORATION
	(Registrant)
Date: March 13, 2018	By:	/s/ John “Robert” Thorson
		John “Robert” Thorson
		Senior Vice President and Chief Financial Officer

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