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 26, 2003 Commission Registrant; State of Incorporation; IRS Employer File Number Address; and Telephone Number Identification Number - ----------- ----------------------------------- --------------------- 1-13739 UNISOURCE ENERGY CORPORATION 86-0786732 (An Arizona Corporation) One South Church, Suite 100 Tucson, AZ 85701 (520) 571-4000 1-5924 TUCSON ELECTRIC POWER COMPANY 86-0062700 (An Arizona Corporation) One South Church, Suite 100 Tucson, AZ 85701 (520) 571-4000 Item 9. Regulation FD Disclosure - --------------------------------- The information in this report is being furnished pursuant to Item 12 "Disclosure of Results of Operations and Financial Condition." On April 26, 2003, UniSource Energy Corporation (UniSource Energy) issued a press release announcing first quarter 2003 earnings for UniSource Energy and Tucson Electric Power Company. A copy of the press release is attached as Exhibit 99. Item 7. Financial Statements and Exhibits - ------------------------------------------ Exhibit 99 UniSource Energy Corporation Press Release, dated April 26, 2003. 2 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, each registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. The signature for each undersigned company shall be deemed to relate only to matters having reference to such company or its subsidiary. UNISOURCE ENERGY CORPORATION ---------------------------- (Registrant) Date: April 28, 2003 /s/ Kevin P. Larson ---------------------------- Kevin P. Larson Vice President and Principal Financial Officer TUCSON ELECTRIC POWER COMPANY ----------------------------- (Registrant) Date: April 28, 2003 /s/ Kevin P. Larson ----------------------------- Kevin P. Larson Vice President and Principal Financial Officer 3