Exhibit 99.1 CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 The undersigned as President and Chief Executive Officer of the Company, and acting Chief Financial Officer of the Company, does hereby certify that the foregoing Quarterly Report of CLAIMSNET.COM INC. (the "Company") on Form 10-Q for the period ending June 30, 2002 (the "Report"): (1) Fully complies with the requirements of section 13 or 15(d) of the Securities Exchange Act of 1934; and (2) Fairly presents, in all material respects, the financial condition and result of operations of the Company. /s/ Paul W. Miller Paul W. Miller President and Chief Executive Officer August 14, 2002