X0609 4 2026-08-26 0 0002115119 Columbia Financial, Inc./MD/ CLBK 0001949911 Prabhu Manesh Balachandran false 19-01 ROUTE 208 NORTH FAIR LAWN NJ 07410 0 1 0 0 EVP & CIO 0 Common Stock 2026-08-26 4 A 0 9.6781 11.62 A 2258.7747 I By Stock-Based Deferral Plan Common Stock 15613 D Common Stock 15000 I By IRA Common Stock 4601 I By 401(k) Common Stock 7114 I By ESOP Common Stock 1911 I By SERP Common Stock 22628 I By Stock Award III Common Stock 24239 I By Stock Award IV Stock Options (right to buy) 9.34 2023-10-31 2032-10-31 Common Stock 28567 28567 D Stock Options (right to buy) 7.25 2024-05-01 2033-05-01 Common Stock 18609 18609 D Stock Options (right to buy) 7.50 2025-03-06 2034-03-06 Common Stock 18251 18251 D Stock Options (right to buy) 7.38 2026-03-03 2035-03-03 Common Stock 41989 41989 D Stock Options (right to buy) 8.31 2027-03-02 2036-03-02 Common Stock 42999 42999 D Phantom Stock Unit Common Stock 16871 16871 I Deferred Stock Unit Plan Represents phantom stock dividends which are exempt under Rule 16b-3 in connection with the Columbia Bank Stock Based Deferral Plan. This form reflects increases in beneficial ownership resulting from exempt acquisitions pursuant to rule 16b-3(c). This form accounts for a decrease of 2 share from the prior report due to the rounding of fractional shares. Stock Awards granted pursuant to the Columbia Financial, Inc. 2019 Equity Incentive plan, 25% of which vest in three approximately equal annual installments commencing on March 6, 2025; and the remaining 75% of which vest upon achievement of certain specified performance-based vesting criteria, which if achieved, such Awards would vest three years after the date of the Award. Stock Awards granted pursuant to the Columbia Financial, Inc. 2019 Equity Incentive plan, which vest upon achievement of certain specified performance-based vesting criteria, which if achieved, such Awards would vest three years after the date of the Award on March 3, 2028. Stock Options granted pursuant to the Columbia Financial, Inc. 2019 Equity Incentive Plan are fully vested and exercisable. Stock Options granted pursuant to the Columbia Financial, Inc. 2019 Equity Incentive Plan vest in three approximately equal annual installments commencing on March 6, 2025. Stock Options granted pursuant to the Columbia Financial, Inc. 2019 Equity Incentive Plan vest in three approximately equal annual installments commencing on March 3, 2026. Stock Options granted pursuant to the Columbia Financial, Inc. 2019 Equity Incentive Plan vest in three approximately equal annual installments commencing on March 2, 2027. One phantom stock unit is the economic equivalent of one share of CLBK Common Stock. Phantom stock units were granted under the Columbia Financial, Inc. 2026 Phantom Stock Plan and will be settled in cash upon distribution. On the settlement date, phantom stock units will be payable in cash. The cash value will be calculated, in accordance with the Columbia Financial, Inc. 2026 Phantom Stock Plan, based on the closing stock price of the Company's Common Stock on the determination date. /s/ Thomas F. Splaine, Jr., Power of Attorney 2026-08-28