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                                                                  Exhibit 99.1


                   CERTIFICATION OF CEO AND CFO PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report of Key Energy Services, Inc. (the
"Company") on Form 10-K for the annual period ending June 30, 2002 as filed with
the Securities and Exchange Commission on the date hereof (the "Report"),
Francis D. John, as Chief Executive Officer of the Company, and Royce W.
Mitchell, as Chief Financial Officer of the Company, each hereby certifies,
pursuant to 18 U.S.C. ss. 1350, as adopted pursuant to ss. 906 of the
Sarbanes-Oxley Act of 2002, that, to the best of his knowledge:

      (1) The Report fully complies with the requirements of Section 13(a) or
Section 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 result of operations of the
Company.


/s/ FRANCIS D. JOHN
- ------------------------
Francis D. John
Chief Executive Officer
September 30, 2002


/s/ ROYCE W. MITCHELL
- ------------------------
Royce W. Mitchell
Chief Financial Officer
September 30, 2002