Columbia Banking System (COLB) investor relations material

Opening remarks and agenda

• Meeting held online to maximize shareholder participation and facilitate voting and questions.

• Retiring directors Maria Pope and Mae Numata were recognized for their years of service.

• Introduction of board members and executive management team, including new members from the Pac Premier acquisition.

• Meeting agenda included business proceedings, a presentation, and a Q&A session.

Board and executive committee updates

• Luis Machuca to serve as Lead Independent Director following the meeting.

• Several new directors joined from Pacific Premier Bancorp after its acquisition.

• Executive team includes long-tenured leaders and new talent added in 2025.

Shareholder proposals

• Three proposals: election of 12 directors for a one-year term, advisory vote on executive compensation, and ratification of Deloitte as auditor.

• Motions for all proposals were made, seconded, and submitted for shareholder action.