Form 8-K

8-K — CALIFORNIA WATER SERVICE GROUP

Accession: 0001104659-26-051525

Filed: 2026-04-29

Period: 2026-04-29

CIK: 0001035201

SIC: 4941 (WATER SUPPLY)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — tm2613008d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2613008d1_ex99-1.htm)

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0001035201

2026-04-29

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

Current Report Pursuant to Section 13

or 15(d) of

The Securities Exchange Act of 1934

Date of Report (date of earliest event

reported): April 29, 2026

CALIFORNIA WATER SERVICE GROUP

(Exact name of Registrant as Specified in its

Charter)

Delaware

(State or other jurisdiction

of incorporation)

1-13883

(Commission file number)

77-0448994

(I.R.S. Employer

Identification Number)

1720 North First Street

San Jose, California

(Address of principal executive offices)

95112

(Zip Code)

(408) 367-8200

(Registrant’s telephone number, including

area code)

N/A

(Former name or former address, if changed

since last report)

Check the appropriate box below if the Form 8-K filing

is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act

(17 CFR 240.14d-2(b))

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act

(17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of

the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Shares, par value $0.01

CWT

New York Stock Exchange

Indicate by check mark whether the registrant is an emerging

growth company as defined by Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of

the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth

company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or

revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 8.01.

Other Events

On April

29, 2026, California Water Service Group issued a press release (a copy of which is attached hereto as Exhibit 99.1 and incorporated herein

by reference) announcing the declaration of a quarterly dividend of $0.3350 per common share. The quarterly dividend will be payable on

May 22, 2026 to stockholders of record as of the close of business on May 11, 2026.

Item 9.01.

Financial Statements and Exhibits.

(d) Exhibits.

We hereby file the following exhibit with this

report:

Exhibit No.

Description

99.1

Press Release issued April 29, 2026

104

Cover Page Interactive Date File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities

Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

CALIFORNIA WATER SERVICE GROUP

Date: April 29, 2026

By:

/s/ James P. Lynch

Name:

James P. Lynch

Title:

Senior Vice President, Chief Financial Officer and Treasurer

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2613008d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

DATE: April 29, 2026

CONTACT: Shannon Dean, sdean@calwater.com, (408) 367-8243

Jim Lynch, (408) 367-8200

For Immediate Release

California

Water Service Group Board of Directors

Declares

325th Consecutive Quarterly Dividend

SAN JOSE, Calif., April 29,

2026 — At its meeting on April 29, 2026, the California Water Service Group (NYSE: CWT) Board of Directors declared the

Company’s 325th consecutive quarterly dividend in the amount of $0.3350 per common share, payable on May 22, 2026,

to stockholders of record as of the close of business on May 11, 2026.

About California Water Service

Group

California Water Service Group

is the largest regulated water utility in the western United States. It provides high-quality, reliable water and/or wastewater services

to more than 2.2 million people in California, Hawaii, New Mexico, Washington, and Texas through its regulated subsidiaries, California

Water Service, Hawaii Water Service, New Mexico Water Service, and Washington Water Service, and its utility holding company, Texas Water

Service. This year, the company commemorates a century of service.

Group’s purpose is to

enhance the quality of life for customers, communities, employees, and stockholders. To do so, it invests responsibly in water and

wastewater infrastructure, sustainability initiatives, and community well-being. The company’s nearly 1,300 employees live

by a set of strong core values and share a commitment to protecting the planet, caring for people, and operating with the utmost integrity.

The company has been named one of “America’s Most Responsible Companies” and the “World’s Most Trustworthy

Companies” by Newsweek, a USA Top Workplace, and a Great Place to Work®. More information is available at www.calwatergroup.com.

Forward Looking Statements

This news release contains forward-looking statements within

the meaning established by the Private Securities Litigation Reform Act of 1995 (“PSLRA”). The forward-looking statements

are intended to qualify under provisions of the federal securities laws for “safe harbor” treatment established by the PSLRA.

Forward-looking statements in this news release are based on currently available information, expectations, estimates, assumptions and

projections, and our management’s beliefs, assumptions, judgments and expectations about us, the water utility industry and general

economic conditions. These statements are not statements of historical fact. When used in our documents, statements that are not historical

in nature, including words like will, would, expects, intends, plans, believes, may, could, estimates, assumes, anticipates, projects,

progress, predicts, hopes, targets, forecasts, should, seeks or variations of these words or similar expressions, are intended to identify

forward-looking statements. Examples of forward-looking statements in this news release include, but are not limited to, statements describing

the expected timing of the quarterly dividend payment. Forward-looking statements are not guarantees of future performance. They are

based on numerous assumptions that we believe are reasonable, but they are open to a wide range of uncertainties and business risks.

Consequently, actual results or outcomes may vary materially from what is contained in a forward-looking statement. Factors that may

cause actual results or outcomes to be different than those expected or anticipated include, but are not limited to, those described

under the section entitled “Risk Factors” and elsewhere in our most recent Annual Report on Form 10-K, our subsequent

Quarterly Reports on Form 10-Q, and our other Securities and Exchange Commission filings. In light of these risks, uncertainties,

and assumptions, investors are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date of

this news release. We are not under any obligation, and we expressly disclaim any obligation, to update or alter any forward-looking

statements, whether as a result of new information, future events, or otherwise.

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