COLUMBIA BANKING SYSTEM, INC. REPORTS FOURTH QUARTER 2025 RESULTS

$215 million $243 million $0.72 $0.82 Net income Operating net income1 Earnings per common share - diluted Operating earnings per common share - diluted1 CEO Commentary "Our fourth quarter performance marked a strong end to a tremendous year for Columbia, reflecting continued momentum across our businesses and our commitment to consistent, repeatable results," said Clint Stein, President and CEO. "Our operating performance was supported by disciplined balance sheet management, new and expanding customer relationships, and the first full-quarter contribution from Pacific Premier. We remain on track for a seamless systems conversion later this quarter, which will enable us to fully realize deal- related cost savings and achieve a clean expense run rate by the third quarter. Investments made throughout 2025 strengthened our western footprint and enhanced our long-term earnings power, and we entered 2026 with healthy pipelines, solid capital generation, and a clear path to continued