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 In connection with the Annual Report on Form 10-K of PolyOne Corporation (the "Company") for the period ending December 31, 2002 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Thomas A. Waltermire, Chairman of the Board, President and Chief Executive Officer of the Company, do hereby certify, pursuant to 18 U.S.C. ss. 1350, as adopted pursuant to ss. 906 of the Sarbanes-Oxley Act of 2002, that, to my knowledge: (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 result of operations of the Company. /s/ Thomas A. Waltermire Thomas A. Waltermire Chairman of the Board, President and Chief Executive Officer March 25, 2003 A signed original of this written statement required by Section 906 has been provided to PolyOne Corporation and will be retained by PolyOne Corporation and furnished to the Securities and Exchange Commission or its staff upon request.