Exhibit 31(b)

                                 CERTIFICATION
               Pursuant to Section 302 of the Sarbanes-Oxley Act


     I, Kevin P. Larson, certify that:

1.   I have reviewed this quarterly report on Form 10-Q of UniSource Energy
     Corporation;

2.   Based on my knowledge, this quarterly report does not contain any untrue
     statement of a material fact or omit to state a material fact necessary
     to make the statements made, in light of the circumstances under which
     such statements were made, not misleading with respect to the period
     covered by this quarterly report;

3.   Based on my knowledge, the financial statements, and other
     financial information included in this quarterly report, fairly
     present in all material respects the financial condition, results
     of operations and cash flows of the registrant as of, and for,
     the periods presented in this quarterly report;

4.   The registrant's other certifying officers and I are responsible
     for establishing and maintaining disclosure controls and procedures
     (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
     registrant and we have:

     a.   Designed such disclosure controls and procedures, or caused
          such disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          registrant, including its consolidated subsidiaries, is made
          known to us by others within those entities, particularly during
          the period in which this quarterly report is being prepared;

     b.   Evaluated the effectiveness of the registrant's disclosure
          controls and procedures and presented in this report our
          conclusions about the effectiveness of the disclosure controls
          and procedures, as of the end of the period covered by this
          quarterly report based on such evaluation; and

     c.   Disclosed in this quarterly report any change in the
          registrant's internal control over financial reporting that
          occurred during the registrant's most recent fiscal quarter that
          has materially affected, or is reasonably likely to materially
          affect, the registrant's internal control over financial
          reporting; and

5.   The registrant's other certifying officers and I have disclosed, based
     on our most recent evaluation of internal control over financial
     reporting, to the registrant's auditors and the audit committee of the
     registrant's board of directors (or persons performing the equivalent
     functions):

     a.   All significant deficiencies and material weaknesses in the
          design or operation of internal control over financial reporting
          which are reasonably likely to adversely affect the registrant's
          ability to record, process, summarize and report financial
          information; and

     b.   Any fraud, whether or not material, that involves management
          or other employees who have a significant role in the
          registrant's internal control over financial reporting.




Date:  November 10, 2003                     /s/ Kevin P. Larson
                                            -----------------------------------
                                                 Kevin P. Larson
                                                 Vice President, Chief Financial
                                                 Officer and Treasurer