Exhibit 21
UNS Energy Corporation Subsidiaries
Subsidiary	State or Other Jurisdiction of Incorporation or Organization
Tucson Electric Power Company (TEP)	Arizona
TEP Subsidiaries:
San Carlos Resources Inc.	Arizona
Escavada Company	Arizona
UniSource Energy Services, Inc. (UES)	Arizona
UES Subsidiaries:
UNS Electric, Inc.	Arizona
UNS Gas, Inc.	Arizona