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SLM Corporation

Medium Term Notes, Series B

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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. 221   Trade Date:   2/23/2004
(To Prospectus dated January 23, 2003 and   Issue Date:   2/26/2004
Prospectus Supplement dated January 23, 2003)        

The date of this Pricing Supplement is 2/23/2004

 
   
   
   
   
  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

78490FKF5   FLOAT   6/15/2009   100%   0.750%   Quarterly(4)   06/15/04   No   No       1,635,000   1,622,737.50   N

      


 

 


 

 


 

 


 

 


 

 


 

 

Floating Rate Index

  Spread
  Reset
Period(4)

  Accrual Method
  Maximum
Interest
Rate

  Minimum
Interest
Rate

   
91 Day T-Bill   0.600%   Weekly   Actual/Actual (Payment Basis)   N/A   N/A    

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.
(4)
On the Interest Reset Date, which is the day after the 3 month T Bill auction, the Calculation Agent will establish the new rate based on the BEY for the 3 month T Bill auction pulished in H.15 (http://www.publicdebt.treas.gov/of/ofrespr.htm).

In the event that the results of the 91 day Treasury Bill auction ceases to be published or reported, or that no auction is held in a particular week, then the rate in effect as a result of the last such report will remain in effect until such time, as the results of auctions of 91 day Treasury Bills will again be published.




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SLM Corporation Medium Term Notes, Series B