EXHIBIT 99.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER
PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 (18 U.S.C. 1350)

The undersigned, Steven G. Mihaylo, Chairman of the Board of Directors,
President and Chief Executive Officer of Inter-Tel, Incorporated (the
"Company"), has executed this certification in connection with the filing with
the Securities and Exchange Commission of the Company's Quarterly Report on Form
10-Q for the quarter ended June 30, 2002 (the "Report"). The undersigned hereby
certifies that:

     1.   The Report fully complies with the requirements of Section 13(a) or
          15(d) of the Securities Exchange Act of 1934; and

     2.   The information contained in the Report fairly presents, in all
          material respects, the financial condition and results of operations
          of the Company.

IN WITNESS WHEREOF, the undersigned has executed this certification as of the
14th day of August, 2002.


/s/ Steven G. Mihaylo
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Steven G. Mihaylo
Chairman of the Board of Directors, President and Chief Executive Officer