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EXHIBIT 32.1

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 Quarterly Report of Equifax Inc. (the "Company") on Form 10-Q for the period ended September 30, 2007, as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Richard F. Smith, Chairman and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

Date: October 30, 2007   /s/  RICHARD F. SMITH      
    Richard F. Smith
Chairman and Chief Executive Officer



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