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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. 173   Trade Date:   11/3/03
(To Prospectus dated January 23, 2003 and   Issue Date:   11/6/03
Prospectus Supplement dated January 23, 2003)        

The date of this Pricing Supplement is                11/3/03

 
   
   
   
   
  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

78490FHF9   5.600%   3/15/24   100%   1.875%   Monthly   12/15/03   Yes   Yes   Callable at 100% on 3/15/2008 and continuously thereafter with 20 days notice.   791,000   776,168.75   N

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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SLM Corporation Medium Term Notes, Series B