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Exhibit 99.1

	N E W S        R E L E A S E
FOR IMMEDIATE RELEASE	Media Contacts: Tom Joyce 703/810-5610 Martha Holler 703/810-5178	Investor Contacts: Steve McGarry 703/810-7746 Nam Vu 703/810-7723

SLM CORPORATION SECOND QUARTER LOAN ORIGINATIONS UP 24 PERCENT

Fee Income Businesses Grow 21 Percent

RESTON, Va., July 15, 2004—SLM Corporation (NYSE: SLM), commonly known as Sallie Mae, today reported second-quarter 2004 earnings and performance results that include $2.3 billion in preferred channel loan origination activity, a 24-percent increase from the prior year. Also included in the quarterly figures was a 32-percent jump in originations through Sallie Mae's owned brands, and a 21-percent increase in fee income, driven largely by the company's debt management operation.

        Preferred channel loan originations consist of loans created by the company's owned or affiliated brands. These loans are a key measure of Sallie Mae's market share success and, as an indicator of future loan acquisition volume, drive the company's earnings growth. At quarter end, the company's total managed loan portfolio totaled $94.9 billion, a 14-percent increase from the same time last year.

        In addition, the company reported that it is 98 percent complete in the wind down of its government-sponsored enterprise (GSE), with $2.2 billion in student loans remaining in the GSE, as compared to $16 billion at March 31, 2004. The company now expects to complete its full privatization in early 2005.

        "We are pleased to be able to deliver this earnings growth while moving so near to full privatization," said Albert L. Lord, vice chairman and chief executive officer.

        Sallie Mae reports financial results on a GAAP basis and also presents certain non-GAAP or "core cash" performance measures. The company's equity investors, credit rating agencies and debt capital providers request these "core cash" measures to monitor the company's business performance.

        Sallie Mae reported second-quarter 2004 GAAP net income of $615 million, or $1.36 per diluted share, compared to $373 million, or $.80 per diluted share, in the year-ago period. GAAP net income for the first half of 2004 totaled $906 million compared to $789 million in 2003.

        "Core cash" net income for the quarter was $237 million, up from $210 million in the year-ago period. On a diluted share basis, the company increased 18 percent in the quarter to $.52, compared to $.44 per diluted share in the 2003 second quarter. "Core cash" net interest income was $445 million for the quarter and $879 million for the first half of 2004, up from $393 million and $766 million for the same periods last year.

        "Core cash" other income, which consists primarily of fees earned from guarantor servicing and debt management, was $166 million for the 2004 second quarter, down from $174 million for the prior quarter and up 21 percent from the year-ago quarter's $137 million. "Core cash" operating expenses were $199 million, down from $202 million in the prior quarter, and up from $183 million in the year-ago quarter.

        A description of the "core cash" treatment and a full reconciliation to the GAAP income statement can be found at www.salliemae.com.

        Total equity for the company at June 30, 2004, was $2.9 billion, an increase of $554 million from a year ago. Tangible capital stood at 1.93 percent of managed assets, as compared to 1.81 percent as of June 30, 2003.

        The company will host its regular earnings conference call today at noon. Sallie Mae executives will be on hand to discuss various highlights of the quarter and to answer questions related to the company's performance. Individuals interested in participating should call the following number today, July 15, 2004, starting at 11:45 a.m. EDT: (877) 356-5689 (USA and Canada) or (706) 679-0623 (International). The conference call will be replayed continuously beginning Thursday, July 15, at 3:30 p.m. EDT and concluding at 11:59 p.m. EDT on Thursday, July 22. Please dial (800) 642-1687 (USA and Canada) or dial (706) 645-9291 (International) and use access code 7961444. In addition, there will be a live audio Web cast of the conference call, which may be accessed at www.salliemae.com. A replay will be available 30-45 minutes after the live broadcast.

***

Statements in this release referring to expectations as to future market share, the successful consummation of any business acquisitions and other future developments are forward-looking statements, which involve risks, uncertainties and other factors that may cause the actual results to differ materially from such forward-looking statements. Such factors include, among others, changes in the terms of student loans and the educational credit marketplace arising from the implementation of applicable laws and regulations, and from changes in such laws and regulations, changes in the demand for educational financing or in financing preferences of educational institutions, students and their families, and changes in the general interest rate environment. For more information, see the company's filings with the Securities and Exchange Commission.

***

SLM Corporation (NYSE: SLM), commonly known as Sallie Mae, is the nation's leading provider of education funding, managing nearly $95 billion in student loans for more than 7 million borrowers. The company primarily provides federally guaranteed student loans originated under the Federal Family Education Loan Program (FFELP), and offers comprehensive information and resources to guide students, parents and guidance professionals through the financial aid process. Sallie Mae was established in 1973 as a government-sponsored enterprise (GSE) called the Student Loan Marketing Association, and began the privatization process in 1997. Since then, the parent company name has changed, most recently to SLM Corporation. Through its specialized subsidiaries and divisions, Sallie Mae also provides an array of consumer credit loans, including those for lifelong learning and K-12 education, and business and technical products and services for colleges and universities. More information is available at http://www.salliemae.com. SLM Corporation and its subsidiaries, other than the Student Loan Marketing Association, are not sponsored by or agencies of the United States.

SLM CORPORATION
Supplemental Earnings Disclosure
June 30, 2004
(Dollars in millions, except earnings per share)

	Quarters ended									Six months ended
	June 30, 2004			March 31, 2004			June 30, 2003			June 30, 2004			June 30, 2003
	(unaudited)			(unaudited)			(unaudited)			(unaudited)			(unaudited)
SELECTED FINANCIAL INFORMATION AND RATIOS — (GAAP Basis)
Net income	$	615		$	291		$	373		$	906		$	789
Diluted earnings per common share	$	1.36		$	.64		$	.80		$	2.00		$	1.68
Return on assets		3.61	%		1.86	%		2.90	%		2.77	%		3.14	%
NON-GAAP INFORMATION (See Explanation Below)
"Core cash" net income	$	237		$	231		$	210		$	468		$	413
"Core cash" diluted earnings per common share	$	.52		$	.51		$	.44		$	1.03		$	.87
"Core cash" return on assets		.87	%		.90	%		.93	%		.89	%		.95	%
OTHER OPERATING STATISTICS
Average on-balance sheet student loans	$	54,799		$	52,892		$	44,173		$	53,846		$	44,166
Average off-balance sheet student loans		39,318			37,786			37,811			38,552			36,527
Average Managed student loans	$	94,117		$	90,678		$	81,984		$	92,398		$	80,693
Ending on-balance sheet student loans, net	$	51,577		$	54,414		$	42,993
Ending off-balance sheet student loans, net		43,324			37,735			40,121
Ending Managed student loans, net	$	94,901		$	92,149		$	83,114
Ending Managed FFELP student loans, net	$	85,015		$	83,013		$	76,093
Ending Managed Private Credit Student Loans, net		9,886			9,136			7,021
Ending Managed student loans, net	$	94,901		$	92,149		$	83,114

Non-GAAP "Core Cash" Earnings

        In accordance with the Rules and Regulations of the SEC, we prepare financial statements in accordance with generally accepted accounting principles ("GAAP"). In addition to evaluating the Company's GAAP-based financial information, management, credit rating agencies, lenders and analysts also evaluate the Company on certain non-GAAP performance measures that we refer to as "core cash" measures. While "core cash" measures are not a substitute for reported results under GAAP, we rely on "core cash" measures in operating our business because we believe they provide additional information regarding the operational and performance indicators that are most closely assessed by management.

        We report pro forma "core cash" measures, which are the financial performance measures used by management not only in developing our financial plans and tracking results, but also in establishing corporate performance targets and determining incentive compensation. Our "core cash" measures are not defined terms within GAAP and may not be comparable to similarly titled measures reported by other companies. "Core cash" measures reflect only current period adjustments to GAAP earnings as described below. Accordingly, the Company's "core cash" measures presentation does not represent another comprehensive basis of accounting. A more detailed discussion of the differences between GAAP and "core cash" measures follows.

1)

Securitization: Under GAAP, certain securitization transactions are accounted for as sales of assets. Under "core cash," we present all securitization transactions as long-term non-recourse financings. The upfront "gains" on sale from securitization as well as ongoing "servicing and securitization revenue" presented in accordance with GAAP are excluded from "core cash" and replaced by the interest income, provision for loan losses, and interest expense as they are earned or incurred on the securitized loans.

2)

Derivative Accounting: "Core cash" measures exclude the periodic unrealized gains and losses primarily caused by the one-sided mark-to-market derivative valuations prescribed by Statement of Financial Accounting Standards ("SFAS") No. 133, "Accounting for Derivative Instruments and Hedging Activities," and recognize the economic effect of these hedges, which results in any cash paid or received being recognized ratably as an expense or revenue over the hedged item's life. We also exclude the gain or loss on our equity forward contracts that are required to be accounted for in accordance with SFAS No. 133 as derivatives and are marked to market through earnings.

3)

Floor Income: The timing and amount (if any) of Floor Income earned is uncertain and in excess of expected spreads and, therefore, we exclude such income when it is not economically hedged from "core cash" measures. We employ derivatives, primarily Floor Income Contracts and futures, to economically hedge Floor Income. As discussed in more detail below, these derivatives do not qualify as effective accounting hedges and therefore are marked-to-market through the derivative market value adjustment. For "core cash" measures, we reverse the fair value adjustments on the Floor Income Contracts and futures economically hedging Floor Income and include the amortization of net premiums received (net of Eurodollar futures contracts' realized gains or losses) in income.

4)

Other items: We exclude certain transactions that are not considered part of our core business, including amortization of acquired intangibles, as well as gains and losses on certain sales of securities.

SLM CORPORATION
Consolidated Balance Sheets
(In thousands, except per share amounts)

	June 30, 2004		March 31, 2004		June 30, 2003
	(unaudited)		(unaudited)		(unaudited)
Assets
Federally insured student loans (net of allowance for losses of $8,877; $20,592; and $55,800, respectively)	$	16,729,709	$	26,174,672	$	34,422,041
Federally insured student loans in trust (net of allowance for losses of $33,364; $28,637; and $4,491, respectively)		31,104,748		24,062,169		4,258,526
Private Credit Student Loans (net of allowance for losses of $154,918; $154,222; and $160,350 respectively)		3,742,432		4,176,841		4,312,886
Academic facilities financings and other loans		928,209		1,104,226		1,177,178
Cash and investments		15,242,069		10,294,692		6,788,926
Restricted cash and investments		1,915,538		1,245,828		401,849
Retained Interest in securitized receivables		2,330,360		2,482,242		2,985,777
Goodwill and acquired intangible assets, net		618,930		589,078		583,676
Other assets		3,355,426		3,133,709		3,251,914
Total assets	$	75,967,421	$	73,263,457	$	58,182,773
Liabilities
Short-term borrowings	$	8,063,041	$	16,176,387	$	24,619,758
Borrowings collateralized by loans in trust		31,958,701		24,595,289		4,243,000
Long-term notes		30,078,062		26,710,017		23,806,326
Other liabilities		2,946,951		3,044,113		3,147,517
Total liabilities		73,046,755		70,525,806		55,816,601
Commitments and contingencies*
Stockholders' equity
Preferred stock, par value $.20 per share, 20,000 shares authorized: 3,300; 3,300; and 3,300 shares, respectively, issued at stated value of $50 per share		165,000		165,000		165,000
Common stock, par value $.20 per share, 1,125,000 shares authorized: 478,722; 476,442; and 638,983 shares, respectively, issued		95,745		95,289		127,797
Additional paid-in capital		1,747,284		1,670,640		1,359,082
Accumulated other comprehensive income, net of tax		355,955		534,445		689,220
Retained earnings		1,683,563		1,153,100		3,386,218
Stockholders' equity before treasury stock		4,047,547		3,618,474		5,727,317
Common stock held in treasury at cost: 39,760; 33,533; and 188,491 shares, respectively		1,126,881		880,823		3,361,145
Total stockholders' equity		2,920,666		2,737,651		2,366,172
Total liabilities and stockholders' equity	$	75,967,421	$	73,263,457	$	58,182,773

*

Commitments to purchase loans, lines of credit and letters of credit were $34.6 billion, $1.0 billion and $.3 billion, respectively, at June 30, 2004.

SLM CORPORATION
Consolidated Statements of Income
(In thousands, except per share amounts)

		Quarters ended								Six months ended
		June 30, 2004		March 31, 2004			June 30, 2003			June 30, 2004		June 30, 2003
		(unaudited)		(unaudited)			(unaudited)			(unaudited)		(unaudited)
Interest income:
	Federally insured student loans	$	492,166	$	468,967		$	462,425		$	961,133	$	929,906
	Private Credit Student Loans		76,613		76,589			87,892			153,202		175,464
	Academic facilities financings and other loans		18,126		18,376			19,290			36,502		39,496
	Investments		52,534		43,457			42,034			95,991		70,295
Total interest income			639,439		607,389			611,641			1,246,828		1,215,161
Interest expense			306,832		285,674			257,473			592,506		514,775
Net interest income			332,607		321,715			354,168			654,322		700,386
Less: provision for losses			28,344		39,818			36,449			68,162		78,994
Net interest income after provision for losses			304,263		281,897			317,719			586,160		621,392
Other income:
	Gains on student loan securitizations		197,840		113,954			314,220			311,794		620,023
	Servicing and securitization revenue		124,037		136,658			200,207			260,695		388,819
	Derivative market value adjustment		386,147		(116,743	)		(205,295	)		269,404		(324,358	)
	Guarantor servicing fees		23,249		34,971			25,259			58,220		60,453
	Debt management fees		70,113		79,928			52,684			150,041		111,497
	Other		68,115		58,955			59,083			127,070		108,657
Total other income			869,501		307,723			446,158			1,177,224		965,091
Operating expenses			206,051		208,877			189,867			414,928		369,232
Income before income taxes			967,713		380,743			574,010			1,348,456		1,217,251
Income taxes			352,787		89,278			201,316			442,065		428,008
Net income			614,926		291,465			372,694			906,391		789,243
Preferred stock dividends			2,864		2,886			2,875			5,750		5,750
Net income attributable to common stock		$	612,062	$	288,579		$	369,819		$	900,641	$	783,493
Basic earnings per common share		$	1.39	$	.65			.82		$	2.04	$	1.72
Average common shares outstanding			439,901		442,664			452,174			441,283		454,365
Diluted earnings per common share		$	1.36	$	.64		$	.80		$	2.00	$	1.68
Average common and common equivalent shares outstanding			448,184		451,747			465,132			449,966		467,402
Dividends per common share		$	.19	$	.17		$	.17		$	.36	$	.25

SLM CORPORATION
Pro-Forma "Core Cash"
Consolidated Statements of Income
(In thousands, except per share amounts)

		Quarters ended						Six months ended
		June 30, 2004		March 31, 2004		June 30, 2003		June 30, 2004		June 30, 2003
		(unaudited)		(unaudited)		(unaudited)		(unaudited)		(unaudited)
Managed interest income:
	Managed federally insured student loans	$	710,079	$	687,222	$	643,831	$	1,397,301	$	1,287,778
	Managed Private Credit Student Loans		146,835		113,658		110,469		260,493		208,865
	Academic facilities financings and other loans		18,126		18,376		19,290		36,502		39,496
	Investments		56,026		47,936		43,892		103,962		73,135
Total Managed interest income			931,066		867,192		817,482		1,798,258		1,609,274
Managed interest expense			485,784		433,765		424,274		919,549		843,616
Net Managed interest income			445,282		433,427		393,208		878,709		765,658
Less: provision for losses			40,624		44,968		29,150		85,592		60,756
Net Managed interest income after provision for losses			404,658		388,459		364,058		793,117		704,902
Other income:
	Guarantor servicing fees		23,249		34,971		25,259		58,220		60,453
	Debt management fees		70,113		79,928		52,684		150,041		111,497
	Other		72,252		59,336		58,685		131,588		111,890
Total other income			165,614		174,235		136,628		339,849		283,840
Operating expenses			199,314		202,149		183,283		401,463		356,020
Income before income taxes			370,958		360,545		317,403		731,503		632,722
Income taxes			133,851		129,491		107,841		263,342		219,870
"Core cash" net income			237,107		231,054		209,562		468,161		412,852
Preferred stock dividends			2,864		2,886		2,875		5,750		5,750
"Core cash" net income attributable to common stock		$	234,243	$	228,168	$	206,687	$	462,411	$	407,102
"Core cash" basic earnings per common share		$	.53	$	.52	$	.46	$	1.05	$	.90
Average common shares outstanding			439,901		442,664		452,174		441,283		454,365
"Core cash" diluted earnings per common share		$	.52	$	.51	$	.44	$	1.03	$	.87
Average common and common equivalent shares outstanding			448,184		451,747		465,132		449,966		467,402

SLM CORPORATION
Pro-Forma "Core Cash"
Reconciliation of GAAP Net Income to "Core Cash" Net Income
(In thousands)

		Quarters ended									Six months ended
		June 30, 2004			March 31, 2004			June 30, 2003			June 30, 2004			June 30, 2003
		(unaudited)			(unaudited)			(unaudited)			(unaudited)			(unaudited)
GAAP net income		$	614,926		$	291,465		$	372,694		$	906,391		$	789,243
"Core cash" adjustments:
	Net impact of securitization accounting		(70,822	)		11,089			(247,986	)		(59,733	)		(513,264	)
	Net impact of derivative accounting		(561,534	)		(99,490	)		29,510			(661,024	)		(85,301	)
	Net impact of Floor Income		24,327			60,780			(44,176	)		85,107			(6,885	)
	Amortization of acquired intangibles and other		11,273			7,423			6,045			18,696			20,921
Total "core cash" adjustments before income taxes			(596,756	)		(20,198	)		(256,607	)		(616,954	)		(584,529	)
Net tax effect (A)			218,937			(40,213	)		93,475			178,724			208,138
Total "core cash" adjustments			(377,819	)		(60,411	)		(163,132	)		(438,230	)		(376,391	)
"Core cash" net income		$	237,107		$	231,054		$	209,562		$	468,161		$	412,852

(A)

Such tax effect is based upon the Company's "core cash" effective tax rate for the year. The net tax effect results primarily from the exclusion of the permanent income tax impact of the equity forward contracts.

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Exhibit 99.1

SLM CORPORATION Supplemental Earnings Disclosure June 30, 2004 (Dollars in millions, except earnings per share)
SLM CORPORATION Consolidated Balance Sheets (In thousands, except per share amounts)
SLM CORPORATION Consolidated Statements of Income (In thousands, except per share amounts)
SLM CORPORATION Pro-Forma "Core Cash" Consolidated Statements of Income (In thousands, except per share amounts)
SLM CORPORATION Pro-Forma "Core Cash" Reconciliation of GAAP Net Income to "Core Cash" Net Income (In thousands)