SLM Corporation
Medium Term Notes, Series B

With Maturities of 9 Months or More from Date of Issue

Registration No. 333-90316 Filed Pursuant to Rule 424(b)(3) Pricing Supplement No. 259 (To Prospectus dated January 23, 2003 and Prospectus Supplement dated January 23, 2003)

Trade Date: 4/26/2004 Issue Date: 4/29/2004

The date of this Pricing Supplement is 4/26/2004

										Interest Payment						Subject to Redemption
CUSIP		Stated Interest Rate Per Annum(1)		Maturity Date		Price to Public(2)(3)		Discounts & Commissions		Frequency		First Payment		Survivor's Option		Yes/No		Date and terms of redemption		Aggregate Principal Amount		Net Proceeds		OID Status
78490FLV9		*Step		6/15/2024		100%		2.500%		Semi		12/15/04		No		Yes		Callable at 100% on 6/15/2009 and continuously thereafter with 20 days notice.		819,000		798,525.00		N

*5.00% until but not including 6/15/09, then 6.20% until but not including 6/15/14, then 7.20% until but not including 6/15/19, then 8.00% thereafter

Effective April 7, 2003 the name of Salomon Smith Barney Inc., an agent of the program, was changed to Citigroup Global Markets Inc.

(1)

The interest rates on the Ed Notes may be changed by SLM Corporation from time to time, but any such change will not affect the interest rate on any Ed Notes offered prior to the effective date of the change.

(2)

Expressed as a percentage of aggregate principal amount.

(3)

See "Supplemental Plan of Distribution" in the Prospectus supplement for additional information concerning price to public and underwriting compensation.

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