Exhibit 21

Subsidiaries of the Registrant

Subsidiary Name
State of Incorporation
 
Business Name
California Water Service Company
California
 
California Water Service Company
CWS Utility Services
California
 
CWS Utility Services
New Mexico Water Service Company
New Mexico
 
New Mexico Water Service Company
Washington Water Service Company
Washington
 
Washington Water Service Company
Hawaii Water Service Company, Inc.
Hawaii
 
Hawaii Water Service Company
HWS Utility Services LLC
Hawaii
 
HWS Utility Services