SLM (SLM) 10-Q 2005 Q2 Quarterly report

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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 SLM Corporation (the "Company") on Form 10-Q for the period ended June 30, 2005 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Thomas J. Fitzpatrick, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, 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 result of operations of the Company.

/s/  THOMAS J. FITZPATRICK      Thomas J. Fitzpatrick
President and Chief Executive Officer and Director
August 9, 2005

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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