X0508 4 2026-03-03 0 0001035201 CALIFORNIA WATER SERVICE GROUP CWT 0001998622 James Sophie Marwieh 1720 NORTH FIRST STREET SAN JOSE CA 95112 0 1 0 0 VP Water Qual & Envir Affairs 0 Common Stock 2026-03-03 4 A 0 1650 0.0 A 8327.706 D Common Stock 2026-03-04 4 F 0 233 46.99 D 8094.706 D Restricted stock granted on 3/3/2026 pursuant to the California Water Service Group equity incentive plan in a transaction exempt under Rule 16-b-3 vests with one-third on March 3, 2027, and with the remaining 2/3 vesting quarterly over the succeeding 24 months. Includes shares acquired through Dividend Reinvestment and Employee Stock Purchase Plan Represents the number of shares withheld and surrendered to the issuer to satisfy the tax withholding obligations that arose in connection with the vesting of Restricted Stock (RSA) Award granted on March 4,2025 By: /s/ Michelle R. Mortensen For: Sophie M James 2026-03-05