| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| Merrywell Christopher | Senior Executive VP | C/O COLUMBIA BANKING SYSTEM, INC., 1301 A STREET, TACOMA | /s/ Andrea M. Newburn, Attorney-in-fact | 17 Mar 2026 | 0001796657 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | COLB | Common Stock | Options Exercise | +5,013 | +12% | $26.23* | 46,040 | 13 Mar 2026 | Direct | ||
| transaction | COLB | Common Stock | Tax liability | -1,973 | -4.3% | $26.23* | 44,067 | 13 Mar 2026 | Direct |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Underlying Class | Amount | Exercise Price | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | COLB | Restricted Stock Unit | Options Exercise | -5,013 | -8.9% | $0.000000* | 51,291 | 13 Mar 2026 | Common Stock | 5,013 | Direct | F1 |
| Id | Content |
|---|---|
| F1 | Restricted Stock Units convert into common stock on a one-for-one basis. On February 25, 2025, the reporting person was granted 15,037 Restricted Stock Units, which vest in three annual installments beginning on March 13, 2026. |