Subsequent Event	9 Months Ended
Sep. 30, 2026
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On October 14, 2026, the Company entered into a Note Purchase Agreement, which provides for the issuance of (i) $75.0 million principal amount of 6.08% Senior Unsecured Notes, Series C, due December 15, 2031 (2031 Notes) and (ii) $50.0 million principal amount of 6.41% Senior Unsecured Notes, Series D, due December 15, 2036 (2036 Notes). Also on October 14, 2026, Cal Water entered into a Bond Purchase Agreement, which provides for the issuance of (i) $50.0 million principal amount of 6.49% First Mortgage Bonds, Series 4, due December 15, 2046 (2046 Bonds) and (ii) $100.0 million principal amount of 6.54% First Mortgage Bonds, Series 5, due December 15, 2056 (2056 Bonds). The notes and the bonds are expected to be issued on or before December 31, 2026. The bonds are expected to be issued pursuant to a Sixty-Sixth Supplemental Indenture. Interest on the 2031 Notes and the 2036 Notes will accrue semi-annually and be payable in arrears on June 15 and December 15 of each year, commencing on June 15, 2027. The 2031 Notes and the 2036 Notes will rank equally with the Company’s unsecured revolving credit facility. Interest on the 2046 Bonds and 2056 Bonds will accrue semi-annually and be payable in arrears on June 15 and December 15 of each year, commencing on June 15, 2027. The 2046 Bonds and 2056 Bonds will rank equally with all of Cal Water’s other First Mortgage Bonds and are secured by liens on its properties, subject to certain exceptions and permitted liens. The Company and Cal Water plan to use the net proceeds from the sale of the 2031 Notes, the 2036 Notes, the 2046 Bonds, and the 2056 Bonds to refinance existing indebtedness and for general corporate purposes. The 2031 Notes, the 2036 Notes, the 2046 Bonds, and the 2056 Bonds are not registered under the Securities Act of 1933, as amended, and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements.

On October 14, 2026, the Company entered into a Note Purchase Agreement, which provides for the issuance of (i) $75.0 million principal amount of 6.08% Senior Unsecured Notes, Series C, due December 15, 2031 (2031 Notes) and (ii) $50.0 million principal amount of 6.41% Senior Unsecured Notes, Series D, due December 15, 2036 (2036 Notes). Also on October 14, 2026, Cal Water entered into a Bond Purchase Agreement, which provides for the issuance of (i) $50.0 million

principal amount of 6.49% First Mortgage Bonds, Series 4, due December 15, 2046 (2046 Bonds) and (ii) $100.0 million principal amount of 6.54% First Mortgage Bonds, Series 5, due December 15, 2056 (2056 Bonds). The notes and the bonds are expected to be issued on or before December 31, 2026. The bonds are expected to be issued pursuant to a Sixty-Sixth Supplemental Indenture.

Interest on the 2031 Notes and the 2036 Notes will accrue semi-annually and be payable in arrears on June 15 and December 15 of each year, commencing on June 15, 2027. The 2031 Notes and the 2036 Notes will rank equally with the Company’s unsecured revolving credit facility.

Interest on the 2046 Bonds and 2056 Bonds will accrue semi-annually and be payable in arrears on June 15 and December 15 of each year, commencing on June 15, 2027. The 2046 Bonds and 2056 Bonds will rank equally with all of Cal Water’s other First Mortgage Bonds and are secured by liens on its properties, subject to certain exceptions and permitted liens.

The Company and Cal Water plan to use the net proceeds from the sale of the 2031 Notes, the 2036 Notes, the 2046 Bonds, and the 2056 Bonds to refinance existing indebtedness and for general corporate purposes. The 2031 Notes, the 2036 Notes, the 2046 Bonds, and the 2056 Bonds are not registered under the Securities Act of 1933, as amended, and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements.