Exhibit 99.1

1234567 123,456,789,012.12345 TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: KEEP THIS PORTION FOR YOUR RECORDS DETACH AND RETURN THIS PORTION ONLY THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. The Board of Directors recommends you vote FOR proposals 1 and 2. 1Approval of the Agreement and Plan of Merger, dated as of July 25, 2018, as it may be amended from time to time, by and between Banner Corporation, a Washington corporation, and Skagit Bancorp, Inc., a Washington corporation. For 0 Against 0 Abstain 0 0 0 0 2. Approval of an adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to approve the merger agreement. John Sample attorney, executor, administrator, or other fiduciary, please give full ANY CITY, ON A1A 1A1 partnership name, by authorized officer. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date 02 0000000000 1 OF 1 1 2 0000388019_1 R1.0.1.17 Please sign exactly as your name(s) appear(s) hereon. When signing as title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or Investor Address Line 1 Investor Address Line 2 Investor Address Line 3 Investor Address Line 4 Investor Address Line 5 1234 ANYWHERE STREET SHARES CUSIP # JOB #SEQUENCE # John Sample 234567 234567 1234567 NAME THE COMPANY NAME INC. - COMMON THE COMPANY NAME INC. - CLASS A THE COMPANY NAME INC. - CLASS B THE COMPANY NAME INC. - CLASS C THE COMPANY NAME INC. - CLASS D THE COMPANY NAME INC. - CLASS E THE COMPANY NAME INC. - CLASS F THE COMPA N Y NAME INC. - 401 K CONTROL #  SHARES123,456,789,012.12345 123,456,789,012.12345 123,456,789,012.12345 123,456,789,012.12345 123,456,789,012.12345 123,456,789,012.12345 123,456,789,012.12345 x PAGE1 OF 2 SKAGIT BANCORP, INC. 301 EAST FAIRHAVEN AVENUE BURLINGTON WA 98233 ATTN: Carla Tucker Investor Address Line 1 Investor Address Line 2 Investor Address Line 3 Investor Address Line 4 Investor Address Line 5 8 8 8 1 1234 ANYWHERE STREET ANY CITY, ON A1A 1A1 234567 234567 234567

Important Notice Regarding the Availability of Proxy Materials for the Special Meeting: The Proxy Statement is available at www.proxyvote.com SKAGIT BANCORP, INC. Special Meeting of Shareholders October 15, 2018 6:00 PM This proxy is solicited by the Board of Directors The shareholder(s) hereby appoint(s) Daniel R. Peth and Chad B. Fisher, or either of them, as proxies, each with the power to appoint his substitute, and hereby authorizes them to represent and to vote, as designated on the reverse side of this proxy, all of the shares of common stock of SKAGIT BANCORP, INC. that the shareholder(s) is/are entitled to vote at the Special Meeting of shareholder(s) to be held at 6:00 PM Pacific Time on October 15, 2018 at McIntyre Hall, located at 2501 E. College Way, Mount Vernon, WA 98273, and any adjournment or postponement thereof. This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is made, this proxy will be voted in accordance with the Board of Directors' recommendations. Continued and to be signed on reverse side 0000388019_2 R1.0.1.17