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) June 13, 2013

AMERICAN STATES WATER COMPANY

(Exact name of registrant as specified in its charter)

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))

Section 5 –Corporate Governance and Management

Item 5.03.                             Amendments to Articles of Incorporation or Bylaws; Fiscal Year.

American States Water Company filed a Certificate of Amendment to its Amended and Restated Articles of Incorporation on June 13, 2013 to increase the number of Common Shares which the Company is authorized to issue from 30,000,000 to 60,000,000 and to entitle each shareholder of record on August 15, 2013 to receive on September 3, 2013 one additional Common Share for each Common Share held on the record date.

Section 9 – Financial Statements and Exhibits

Item 9.01.                             Financial Statements and Exhibits.

The following exhibit is filed hereunder:

Exhibit 3.1                         Amended and Restated Articles of Incorporation of American States Water Company, as amended

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.