SLM Corporation
Medium Term Notes, Series B

With Maturities of 9 Months or More from Date of Issue

Registration No. 333-107132 Filed Pursuant to Rule 424(b)(3) Pricing Supplement No. 431 (To Prospectus dated January 5, 2005 and Prospectus Supplement dated January 5, 2005)

Trade Date: 5/16/2005 Issue Date: 5/19/2005

The date of this Pricing Supplement is 5/16/2005

										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
78490FUC1		N/A		06/15/2012		100%		1.250%		Monthly(4)		06/15/05		No		No				7,644,000		7,548,450.00		N

Floating Rate Index		Spread		Reset Period(4)		Accrual Method		Maximum Interest Rate		Minimum Interest Rate
*CPI		1.500%		Monthly		Actual/Actual (Payment Basis)		N/A		0.000%

* During the initial interest period which is from the Issue Date to but not including 06/15/2005, the interest rate will be 4.51%, then the Consumer Price Index (CPI) plus 1.50% thereafter.

(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.

(4)

On the Interest Determination Date, which is on the 15th day of each month during the terms of the notes beginning on 6/15/2005, the Calculation Agent will establish the new rate as described on page S-16 in the prospectus supplements.

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