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Exhibit 99.1

SallieMae N E W S        R E L E A S E

FOR IMMEDIATE RELEASE Media Contacts:
Tom Joyce
703/984-5610
Martha Holler
703/984-5178 Investor Contacts:
Steve McGarry
703/984-6746
Joe Fisher
703/984-5755

SALLIE MAE POSTS STRONG THIRD-QUARTER 2006
PERFORMANCE RESULTS

•

14-Percent Growth in Total Managed Loan Portfolio

•

35-Percent Jump in Preferred-Channel Loans Originated Through Internal Brands

•

29-Percent Increase in Fee Income and Collection Revenue

RESTON, VA., Oct. 19, 2006—SLM Corporation (NYSE: SLM), commonly known as Sallie Mae, today reported third-quarter 2006 earnings and performance results that include a total managed student loan portfolio of $137 billion, a 14-percent increase from the year-ago quarter.

        This increase was driven by a record quarter of education loan purchases that topped $11 billion, a 36-percent increase over the same quarter last year.

        During the 2006 third quarter, the company originated more than $7.8 billion in loans through its preferred channel, with $4.6 billion coming through the company's internal lending brands, a 35-percent increase from the year-ago quarter. Preferred-channel loan originations are loans funded by the company's internal lending brands and external lending partners. Year to date, preferred-channel loan originations totaled $18.6 billion, with nearly $10 billion coming from the company's internal lending brands.

        "Core earnings" net income was $321 million for the 2006 third quarter, and $927 million for the first nine months of 2006. On a diluted share basis, third-quarter 2006 "core earnings" net income was $.73, compared to $.61 in the year-ago period as adjusted for stock-based compensation and one-time items, a 20-percent increase.

        "In the third quarter, we delivered at the high end of our 15 to 20 percent earnings-per-share goal. Our portfolio growth, combined with the performance of our fee-based businesses, continue to position us very well in a growing student loan marketplace. Our ability to grow our earning assets at a record clip in this competitive environment positions us well to continue our long-term earnings growth," said Tim Fitzpatrick, CEO.

        Sallie Mae reports financial results on a GAAP basis and also presents certain "core earnings" performance measures on a basis that differs from GAAP. The company's management, equity investors, credit rating agencies and debt capital providers use these "core earnings" measures to monitor the company's business performance.

Sallie Mae                  •                  12061 Bluemont Way                  •                  Reston,  Va  20190                •                www.SallieMae.com

        Third-quarter 2006 GAAP net income was $263 million, or $.60 per diluted share, compared to $431 million, or $.95 per diluted share, in the year-ago quarter. GAAP net income year to date in 2006 totaled $1.1 billion, compared to $951 million in the same period in 2005. Included in these GAAP results are pre-tax net losses on derivative and hedging activities of $(131) million in the third-quarter 2006 and $(95) million year-to-date 2006, compared to pre-tax net gains of $316 million and $176 million in the respective year-ago periods.

        "Core earnings" net interest income was $601 million in the 2006 third quarter and $1.8 billion year-to-date, up 15 percent from the first nine months of 2005.

        "Core earnings" fee income and collection revenue, which includes fees earned from guarantor servicing, debt management activity and collection revenue, were $219 million in the 2006 third quarter, up 29 percent from the year-ago quarter. Year-to-date 2006, "core earnings" fee income and collection revenue were $585 million, compared to $474 million in the first three quarters of 2005. "Core earnings" operating expenses were $317 million during the third quarter 2006, compared to $271 million in the year-ago quarter.

        Both a description of the "core earnings" treatment and a full reconciliation to the GAAP income statement can be found in the Third Quarter 2006 Supplemental Earnings Disclosure accompanying this press release, which is posted under the Investors page at http://www.salliemae.com/about/investors/stockholderinfo/earningsinfo.

        Total equity for the company at Sept. 30, 2006, was $4.5 billion, up from $4.4 billion at June 30, 2006. The company's tangible capital at the end of the 2006 third quarter was 2.03 percent of managed assets, compared to 2.19 percent at prior quarter end.

        The company will host its quarterly 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, Oct. 19, 2006, 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, Oct. 19, at 3:00 p.m. EDT and concluding at 11:59 p.m. EDT on Thursday, Nov. 2. Please dial (800) 642-1687 (USA and Canada) or dial (706) 645-9291 (International) and use access code 7891213. 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 beginning 30-45 minutes after the live broadcast.

***

Forward Looking Statements:

This press release contains "forward-looking statements" including expectations as to future market share, the success of preferred channel originations and future results. These statements are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Because such statements inherently involve risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Such risks 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.

Sallie Mae                •                12061 Bluemont Way                •                Reston, Va 20190                •                www.SallieMae.com

***

SLM Corporation (NYSE: SLM), commonly known as Sallie Mae, is the nation's leading provider of saving- and paying-for-college programs. The company manages $137 billion in education loans and serves nearly 10 million student and parent customers. Through its Upromise affiliates, the company also manages more than $11 billion in 529 college-savings plans, and assists more than 7 million members with automatic savings through rebates on everyday purchases. Sallie Mae and its subsidiaries offer debt management services as well as business and technical products to a range of business clients, including higher education institutions, student loan guarantors and state and federal agencies. More information is available at www.salliemae.com. SLM Corporation and its subsidiaries are not sponsored by or agencies of the United States of America.

###

SLM CORPORATION

Supplemental Earnings Disclosure

September 30, 2006

(Dollars in millions, except earnings per share)

	Quarters ended									Nine months ended
	September 30, 2006			June 30, 2006			September 30, 2005			September 30, 2006			September 30, 2005
	(unaudited)			(unaudited)			(unaudited)			(unaudited)			(unaudited)
SELECTED FINANCIAL INFORMATION AND RATIOS
GAAP Basis
Net income	$	263		$	724		$	431		$	1,139		$	951
Diluted earnings per common share(1)(2)	$	.60		$	1.52		$	.95		$	2.56		$	2.10
Return on assets		1.10	%		3.20	%		2.01	%		1.65	%		1.60	%
"Core Earnings" Basis(3)
"Core Earnings" net income	$	321		$	320		$	312		$	927		$	847
"Core Earnings" diluted earnings per common share(1)(2)	$	.73		$	.72		$	.69		$	2.09		$	1.87
"Core Earnings" return on assets		.86	%		.90	%		.94	%		.87	%		.90	%
OTHER OPERATING STATISTICS
Average on-balance sheet student loans	$	84,241		$	80,724		$	77,541		$	82,610		$	71,964
Average off-balance sheet student loans		48,226			47,716			40,742			46,027			42,137
Average Managed student loans	$	132,467		$	128,440		$	118,283		$	128,637		$	114,101
Ending on-balance sheet student loans, net	$	88,038		$	82,279		$	81,626
Ending off-balance sheet student loans, net		48,897			47,865			39,008
Ending Managed student loans, net	$	136,935		$	130,144		$	120,634
Ending Managed FFELP Stafford and Other Student Loans, net	$	39,787		$	41,926		$	43,082
Ending Managed Consolidation Loans, net		75,947			69,195			62,161
Ending Managed Private Education Loans, net		21,201			19,023			15,391
Ending Managed student loans, net	$	136,935		$	130,144		$	120,634

⁽¹⁾

In December 2004, the Company adopted the Emerging Issues Task Force ("EITF") Issue No. 04-8, "The Effect of Contingently Convertible Debt on Diluted Earnings per Share," as it relates to the Company's $2 billion in contingently convertible debt instruments ("Co-Cos") issued in May 2003. EITF No. 04-8 requires the shares underlying Co-Cos to be included in diluted earnings per common share computations regardless of whether the market price trigger or the conversion price has been met, using the "if-converted" method. The impact of Co-Cos due to the application of EITF No. 04-8 was to decrease diluted earnings per common share by the following amounts:

	Quarters ended									Nine months ended
	September 30, 2006			June 30, 2006			September 30, 2005			September 30, 2006			September 30, 2005
	(unaudited)			(unaudited)			(unaudited)			(unaudited)			(unaudited)
Impact of Co-Cos on GAAP diluted earnings per common share	$	—		$	(.08	)	$	(.04	)	$	(.07	)	$	(.08	)
Impact of Co-Cos on "Core Earnings" diluted earnings per common share	$	(.01	)	$	(.01	)	$	(.02	)	$	(.04	)	$	(.06	)

1

⁽²⁾

During the first quarter of 2006, the Company adopted the Financial Accounting Standards Board's ("FASB's") Statement of Financial Accounting Standards ("SFAS") No. 123(R), "Share Based Payment," which is a revision of SFAS No. 123, "Accounting for Stock-Based Compensation." SFAS No. 123(R) requires all share based payments to employees to be recognized in the income statement based on their fair values. For the quarters ended September 30, 2006 and June 30, 2006, reported net income attributable to common stock included $10 million and $9 million, respectively, related to stock option compensation expense, net of related tax effects. The following table is a pro forma presentation of the Company's results had SFAS No. 123(R) been in effect for all periods presented.

	Quarters ended						Nine months ended
	September 30, 2006		June 30, 2006		September 30, 2005		September 30, 2006		September 30, 2005
	(unaudited)		(unaudited)		(unaudited)		(unaudited)		(unaudited)
Pro forma GAAP diluted earnings per common share	$	.60	$	1.52	$	.93	$	2.56	$	2.04
Pro forma "Core Earnings" diluted earnings per common share	$	.73	$	.72	$	.67	$	2.09	$	1.81

⁽³⁾

See explanation of "Core Earnings" performance measures under "Reconciliation of "Core Earnings' Net Income to GAAP Net Income."

2

SLM CORPORATION

Consolidated Balance Sheets

(In thousands, except per share amounts)

	September 30, 2006		June 30, 2006		September 30, 2005
	(unaudited)		(unaudited)		(unaudited)
Assets
FFELP Stafford and Other Student Loans (net of allowance for losses of $7,649; $6,890; and $0, respectively)	$	22,613,604	$	21,390,845	$	22,353,605
Consolidation Loans (net of allowance for losses of $10,720; $10,090; and $5,627, respectively)		57,201,754		54,054,932		51,193,725
Private Education Loans (net of allowance for losses of $274,974; $251,582; and $193,332, respectively)		8,222,400		6,832,843		8,078,650
Other loans (net of allowance for losses of $18,327; $15,190; and $13,563, respectively)		1,257,252		1,050,632		1,094,464
Cash and investments		4,248,639		6,204,462		3,773,014
Restricted cash and investments		3,957,535		3,489,542		2,706,925
Retained Interest in off-balance sheet securitized loans		3,613,376		3,151,855		2,330,390
Goodwill and acquired intangible assets, net		1,333,123		1,080,703		1,063,916
Other assets		4,605,014		4,650,851		3,725,670
Total assets	$	107,052,697	$	101,906,665	$	96,320,359
Liabilities
Short-term borrowings	$	3,669,842	$	3,801,266	$	4,652,334
Long-term borrowings		94,816,563		90,506,785		84,499,739
Other liabilities		4,053,931		3,229,477		3,330,763
Total liabilities		102,540,336		97,537,528		92,482,836
Commitments and contingencies
Minority interest in subsidiaries		9,338		9,369		13,725
Stockholders' equity
Preferred stock, par value $.20 per share, 20,000 shares authorized; Series A: 3,300; 3,300; and 3,300 shares, respectively, issued at stated value of $50 per share; Series B: 4,000; 4,000; and 4,000 shares, respectively, issued at stated value of $100 per share		565,000		565,000		565,000
Common stock, par value $.20 per share, 1,125,000 shares authorized: 431,590; 430,753; and 488,525 shares, respectively, issued		86,318		86,151		97,705
Additional paid-in capital		2,490,851		2,440,565		2,107,961
Accumulated other comprehensive income, net of tax		460,527		370,204		407,768
Retained earnings		1,928,204		1,775,948		3,195,034
Stockholders' equity before treasury stock		5,530,900		5,237,868		6,373,468
Common stock held in treasury at cost: 22,229; 19,078; and 69,927 shares, respectively		1,027,877		878,100		2,549,670
Total stockholders' equity		4,503,023		4,359,768		3,823,798
Total liabilities and stockholders' equity	$	107,052,697	$	101,906,665	$	96,320,359

3

SLM CORPORATION

Consolidated Statements of Income

(In thousands, except per share amounts)

		Quarters ended									Nine months ended
		September 30, 2006			June 30, 2006			September 30, 2005			September 30, 2006			September 30, 2005
		(unaudited)			(unaudited)			(unaudited)			(unaudited)			(unaudited)
Interest income:
	FFELP Stafford and Other Student Loans	$	364,621		$	337,090		$	270,444		$	1,000,211		$	699,687
	Consolidation Loans		916,091			841,591			676,820			2,579,017			1,739,670
	Private Education Loans		254,747			233,696			173,467			729,796			429,892
	Other loans		24,550			23,541			21,614			71,398			61,813
	Cash and investments		141,083			124,954			70,541			361,847			186,835
Total interest income			1,701,092			1,560,872			1,212,886			4,742,269			3,117,897
Interest expense			1,363,271			1,204,067			828,122			3,660,122			2,056,585
Net interest income			337,821			356,805			384,764			1,082,147			1,061,312
Less: provisions for losses			67,242			67,396			12,217			194,957			137,688
Net interest income after provisions for losses			270,579			289,409			372,547			887,190			923,624
Other income:
	Gains on student loan securitizations		201,132			671,262			—			902,417			311,895
	Servicing and securitization revenue		187,082			82,842			(16,194	)		368,855			276,698
	Losses on investments, net		(13,427	)		(8,524	)		(43,030	)		(24,899	)		(56,976	)
	Gains (losses) on derivative and hedging activities, net		(130,855	)		122,719			316,469			(94,875	)		176,278
	Guarantor servicing fees		38,848			33,256			35,696			99,011			93,922
	Debt management fees		122,556			90,161			92,727			304,329			261,068
	Collections revenue		57,913			67,357			41,772			181,951			118,536
	Other		87,923			75,081			74,174			234,380			206,187
Total other income			551,172			1,134,154			501,614			1,971,169			1,387,608
Operating expenses			353,494			316,602			291,961			993,405			841,665
Income before income taxes and minority interest in net earnings of subsidiaries			468,257			1,106,961			582,200			1,864,954			1,469,567
Income taxes			203,686			381,828			149,821			722,559			512,860
Income before minority interest in net earnings of subsidiaries			264,571			725,133			432,379			1,142,395			956,707
Minority interest in net earnings of subsidiaries			1,099			1,355			1,029			3,544			5,458
Net income			263,472			723,778			431,350			1,138,851			951,249
Preferred stock dividends			9,221			8,787			7,288			26,309			14,071
Net income attributable to common stock		$	254,251		$	714,991		$	424,062		$	1,112,542		$	937,178
Basic earnings per common share		$	.62		$	1.74		$	1.02		$	2.71		$	2.24
Average common shares outstanding			410,034			410,957			417,235			411,212			419,205
Diluted earnings per common share		$	.60		$	1.52		$	.95		$	2.56		$	2.10
Average common and common equivalent shares outstanding			449,841			454,314			458,798			452,012			461,222
Dividends per common share		$	.25		$	.25		$	.22		$	.72		$	.63

4

SLM CORPORATION

Segment and "Core Earnings"

Consolidated Statements of Income

(In thousands)

		Quarter ended September 30, 2006
		Lending		DMO			Corporate and Other			Total "Core Earnings"		Adjustments			Total GAAP
		(unaudited)
Interest income:
	FFELP Stafford and Other Student Loans	$	701,615	$	—		$	—		$	701,615	$	(336,994	)	$	364,621
	Consolidation Loans		1,241,999		—			—			1,241,999		(325,908	)		916,091
	Private Education Loans		557,787		—			—			557,787		(303,040	)		254,747
	Other loans		24,550		—			—			24,550		—			24,550
	Cash and investments		206,837		—			2,782			209,619		(68,536	)		141,083
Total interest income			2,732,788		—			2,782			2,735,570		(1,034,478	)		1,701,092
Total interest expense			2,124,587		6,088			3,515			2,134,190		(770,919	)		1,363,271
Net interest income			608,201		(6,088	)		(733	)		601,380		(263,559	)		337,821
Less: provisions for losses			79,774		—			(3	)		79,771		(12,529	)		67,242
Net interest income after provisions for losses			528,427		(6,088	)		(730	)		521,609		(251,030	)		270,579
Fee income			—		122,556			38,848			161,404		—			161,404
Collections revenue			—		57,744			—			57,744		169			57,913
Other income			46,074		—			40,988			87,062		244,793			331,855
Operating expenses(1)			156,168		91,341			69,644			317,153		36,341			353,494
Income before income taxes and minority interest in net earnings of subsidiaries			418,333		82,871			9,462			510,666		(42,409	)		468,257
Income tax expense(2)			154,783		30,662			3,502			188,947		14,739			203,686
Minority interest in net earnings of subsidiaries			—		1,099			—			1,099		—			1,099
Net income		$	263,550	$	51,110		$	5,960		$	320,620	$	(57,148	)	$	263,472

⁽¹⁾

Operating expenses for the Lending, DMO, and Corporate and Other Business segments include $8 million, $4 million, and $4 million, respectively, of stock-based compensation expense due to the implementation of SFAS No. 123(R) in the first quarter of 2006.

⁽²⁾

Income taxes are based on a percentage of net income before tax for the individual reportable segment.

5

		Quarter ended June 30, 2006
		Lending		DMO			Corporate and Other			Total "Core Earnings"		Adjustments			Total GAAP
		(unaudited)
Interest income:
	FFELP Stafford and Other Student Loans	$	718,909	$	—		$	—		$	718,909	$	(381,819	)	$	337,090
	Consolidation Loans		1,114,355		—			—			1,114,355		(272,764	)		841,591
	Private Education Loans		485,429		—			—			485,429		(251,733	)		233,696
	Other loans		23,541		—			—			23,541		—			23,541
	Cash and investments		169,877		—			659			170,536		(45,582	)		124,954
Total interest income			2,512,111		—			659			2,512,770		(951,898	)		1,560,872
Total interest expense			1,903,523		5,466			1,345			1,910,334		(706,267	)		1,204,067
Net interest income			608,588		(5,466	)		(686	)		602,436		(245,631	)		356,805
Less: provisions for losses			60,009		—			(32	)		59,977		7,419			67,396
Net interest income after provisions for losses			548,579		(5,466	)		(654	)		542,459		(253,050	)		289,409
Fee income			—		90,161			33,256			123,417		—			123,417
Collections revenue			—		67,213			—			67,213		144			67,357
Other income			50,771		—			24,338			75,109		868,271			943,380
Operating expenses(1)			163,162		85,110			50,235			298,507		18,095			316,602
Income before income taxes and minority interest in net earnings of subsidiaries			436,188		66,798			6,705			509,691		597,270			1,106,961
Income tax expense(2)			161,391		24,715			2,480			188,586		193,242			381,828
Minority interest in net earnings of subsidiaries			—		1,355			—			1,355		—			1,355
Net income		$	274,797	$	40,728		$	4,225		$	319,750	$	404,028		$	723,778

⁽¹⁾

Operating expenses for the Lending, DMO, and Corporate and Other Business segments include $8 million, $2 million, and $4 million, respectively, of stock-based compensation expense due to the implementation of SFAS No. 123(R) in the first quarter of 2006.

⁽²⁾

Income taxes are based on a percentage of net income before tax for the individual reportable segment.

6

		Quarter ended September 30, 2005
		Lending(2)			DMO(2)			Corporate and Other(2)			Total "Core Earnings"			Adjustments			Total GAAP
		(unaudited)
Interest income:
	FFELP Stafford and Other Student Loans	$	585,984		$	—		$	—		$	585,984		$	(315,540	)	$	270,444
	Consolidation Loans		832,893			—			—			832,893			(156,073	)		676,820
	Private Education Loans		312,184			—			—			312,184			(138,717	)		173,467
	Other loans		21,614			—			—			21,614			—			21,614
	Cash and investments		112,347			—			1,366			113,713			(43,172	)		70,541
Total interest income			1,865,022			—			1,366			1,866,388			(653,502	)		1,212,886
Total interest expense			1,299,316			5,689			1,772			1,306,777			(478,655	)		828,122
Net interest income			565,706			(5,689	)		(406	)		559,611			(174,847	)		384,764
Less: provisions for losses			(719	)		—			539			(180	)		12,397			12,217
Net interest income after provisions for losses			566,425			(5,689	)		(945	)		559,791			(187,244	)		372,547
Fee income			—			92,727			35,696			128,423			—			128,423
Collections revenue			—			41,772			—			41,772			—			41,772
Other income			106			(66	)		36,859			36,899			294,520			331,419
Operating expenses			133,850			71,718			65,025			270,593			21,368			291,961
Income before income taxes and minority interest in net earnings of subsidiaries			432,681			57,026			6,585			496,292			85,908			582,200
Income tax expense(1)			160,092			21,099			2,437			183,628			(33,807	)		149,821
Minority interest in net earnings of subsidiaries			—			1,029			—			1,029			—			1,029
Net income		$	272,589		$	34,898		$	4,148		$	311,635		$	119,715		$	431,350

⁽¹⁾

Income taxes are based on a percentage of net income before tax for the individual reportable segment.

⁽²⁾

In the first quarter of 2006, the Company changed its method for allocating certain Corporate and Other expenses to the other business segments. All periods presented have been updated to reflect the new allocation methodology.

7

		Nine months ended September 30, 2006
		Lending		DMO			Corporate and Other			Total "Core Earnings"		Adjustments			Total GAAP
		(unaudited)
Interest income:
	FFELP Stafford and Other Student Loans	$	2,070,275	$	—		$	—		$	2,070,275	$	(1,070,064	)	$	1,000,211
	Consolidation Loans		3,384,316		—			—			3,384,316		(805,299	)		2,579,017
	Private Education Loans		1,471,976		—			—			1,471,976		(742,180	)		729,796
	Other loans		71,398		—			—			71,398		—			71,398
	Cash and investments		507,175		—			4,764			511,939		(150,092	)		361,847
Total interest income			7,505,140		—			4,764			7,509,904		(2,767,635	)		4,742,269
Total interest expense			5,687,482		16,710			6,138			5,710,330		(2,050,208	)		3,660,122
Net interest income			1,817,658		(16,710	)		(1,374	)		1,799,574		(717,427	)		1,082,147
Less: provisions for losses			214,603		—			(16	)		214,587		(19,630	)		194,957
Net interest income after provisions for losses			1,603,055		(16,710	)		(1,358	)		1,584,987		(697,797	)		887,190
Fee income			—		304,329			99,011			403,340		—			403,340
Collections revenue			—		181,497			—			181,497		454			181,951
Other income			137,417		—			95,335			232,752		1,153,126			1,385,878
Operating expenses(1)			480,768		265,964			178,391			925,123		68,282			993,405
Income before income taxes and minority interest in net earnings of subsidiaries			1,259,704		203,152			14,597			1,477,453		387,501			1,864,954
Income tax expense(2)			466,091		75,166			5,401			546,658		175,901			722,559
Minority interest in net earnings of subsidiaries			—		3,544			—			3,544		—			3,544
Net income		$	793,613	$	124,442		$	9,196		$	927,251	$	211,600		$	1,138,851

⁽¹⁾

Operating expenses for the Lending, DMO, and Corporate and Other Business segments include $26 million, $9 million, and $13 million, respectively, of stock-based compensation expense due to the implementation of SFAS No. 123(R) in the first quarter of 2006.

⁽²⁾

Income taxes are based on a percentage of net income before tax for the individual reportable segment.

8

		Nine months ended September 30, 2005
		Lending(2)		DMO(2)			Corporate and Other(2)			Total "Core Earnings"		Adjustments			Total GAAP
		(unaudited)
Interest income:
	FFELP Stafford and Other Student Loans	$	1,678,268	$	—		$	—		$	1,678,268	$	(978,581	)	$	699,687
	Consolidation Loans		2,080,287		—			—			2,080,287		(340,617	)		1,739,670
	Private Education Loans		786,439		—			—			786,439		(356,547	)		429,892
	Other loans		61,813		—			—			61,813		—			61,813
	Cash and investments		268,195		—			3,170			271,365		(84,530	)		186,835
Total interest income			4,875,002		—			3,170			4,878,172		(1,760,275	)		3,117,897
Total interest expense			3,290,419		13,645			4,543			3,308,607		(1,252,022	)		2,056,585
Net interest income			1,584,583		(13,645	)		(1,373	)		1,569,565		(508,253	)		1,061,312
Less: provisions for losses			68,783		—			184			68,967		68,721			137,688
Net interest income after provisions for losses			1,515,800		(13,645	)		(1,557	)		1,500,598		(576,974	)		923,624
Fee income			—		261,068			93,922			354,990		—			354,990
Collections revenue			—		118,536			—			118,536		—			118,536
Other income			72,004		1			97,731			169,736		744,346			914,082
Operating expenses			408,627		203,130			179,535			791,292		50,373			841,665
Income before income taxes and minority interest in net earnings of subsidiaries			1,179,177		162,830			10,561			1,352,568		116,999			1,469,567
Income tax expense(1)			436,295		60,247			3,908			500,450		12,410			512,860
Minority interest in net earnings of subsidiaries			1,749		3,449			—			5,198		260			5,458
Net income		$	741,133	$	99,134		$	6,653		$	846,920	$	104,329		$	951,249

⁽¹⁾

Income taxes are based on a percentage of net income before tax for the individual reportable segment.

⁽²⁾

In the first quarter of 2006, the Company changed its method for allocating certain Corporate and Other expenses to the other business segments. All periods presented have been updated to reflect the new allocation methodology.

9

SLM CORPORATION

Reconciliation of "Core Earnings" Net Income to GAAP Net Income

(In thousands, except per share amounts)

		Quarters ended									Nine months ended
		September 30, 2006			June 30, 2006			September 30, 2005			September 30, 2006			September 30, 2005
		(unaudited)			(unaudited)			(unaudited)			(unaudited)			(unaudited)
"Core Earnings" net income(A)		$	320,620		$	319,750		$	311,635		$	927,251		$	846,920
"Core Earnings" adjustments:
	Net impact of securitization accounting		159,468			503,083			(252,748	)		600,490			(177,589	)
	Net impact of derivative accounting		(112,699	)		164,678			409,082			13,162			487,705
	Net impact of Floor Income		(52,781	)		(52,333	)		(54,318	)		(157,683	)		(147,835	)
	Net impact of acquired intangibles(B)		(36,397	)		(18,158	)		(16,108	)		(68,468	)		(45,282	)
Total "Core Earnings" adjustments before income taxes and minority interest in net earnings of subsidiaries			(42,409	)		597,270			85,908			387,501			116,999
Net tax effect(C)			(14,739	)		(193,242	)		33,807			(175,901	)		(12,410	)
Total "Core Earnings" adjustments before minority interest in net earnings of subsidiaries			(57,148	)		404,028			119,715			211,600			104,589
	Minority interest in net earnings of subsidiaries		—			—			—			—			(260	)
Total "Core Earnings" adjustments			(57,148	)		404,028			119,715			211,600			104,329
GAAP net income		$	263,472		$	723,778		$	431,350		$	1,138,851		$	951,249
GAAP diluted earnings per common share		$	.60		$	1.52		$	.95		$	2.56		$	2.10

^(A) "Core Earnings" diluted earnings per common share $ .73 $ .72 $ .69 $ 2.09 $ 1.87

^(B)

Represents goodwill and intangible impairment and the amortization of acquired intangibles.

^(C)

Such tax effect is based upon the Company's "Core Earnings" 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.

"Core Earnings"

        In accordance with the Rules and Regulations of the Securities and Exchange Commission ("SEC"), we prepare financial statements in accordance with generally accepted accounting principles in the United States of America ("GAAP"). In addition to evaluating the Company's GAAP-based financial information, management evaluates the Company's business segments on a basis that, as allowed under SFAS No. 131, "Disclosures about Segments of an Enterprise and Related Information," differs from GAAP. We refer to management's basis of evaluating our segment results as "Core Earnings" presentations for each business segment and we refer to this information in our presentations with credit rating agencies and lenders. While "Core Earnings" are not a substitute for reported results under GAAP, we rely on "Core Earnings" to manage each operating segment because

10

we believe these measures provide additional information regarding the operational and performance indicators that are most closely assessed by management.

        Our "Core Earnings" are the primary financial performance measures used by management to evaluate performance and to allocate resources. Accordingly, financial information is reported to management on a "Core Earnings" basis by reportable segment, as these are the measures used regularly by our chief operating decision maker. Our "Core Earnings" are used in developing our financial plans and tracking results, and also in establishing corporate performance targets and determining incentive compensation. Management believes this information provides additional insight into the financial performance of the Company's core business activities. Our "Core Earnings" are not defined terms within GAAP and may not be comparable to similarly titled measures reported by other companies. "Core Earnings" reflect only current period adjustments to GAAP as described below. Accordingly, the Company's "Core Earnings" presentation does not represent another comprehensive basis of accounting. A more detailed discussion of the differences between GAAP and "Core Earnings" follows.

Limitations of "Core Earnings"

        While GAAP provides a uniform, comprehensive basis of accounting, for the reasons described above, management believes that "Core Earnings" are an important additional tool for providing a more complete understanding of the Company's results of operations. Nevertheless, "Core Earnings" are subject to certain general and specific limitations that investors should carefully consider. For example, as stated above, unlike financial accounting, there is no comprehensive, authoritative guidance for management reporting. Our "Core Earnings" are not defined terms within GAAP and may not be comparable to similarly titled measures reported by other companies. Unlike GAAP, "Core Earnings" reflect only current period adjustments to GAAP. Accordingly, the Company's "Core Earnings" presentation does not represent a comprehensive basis of accounting. Investors, therefore, may not compare our Company's performance with that of other financial services companies based upon "Core Earnings." "Core Earnings" results are only meant to supplement GAAP results by providing additional information regarding the operational and performance indicators that are most closely used by management, the Company's board of directors, rating agencies and lenders to assess performance.

        Other limitations arise from the specific adjustments that management makes to GAAP results to derive "Core Earnings" results. For example, in reversing the unrealized gains and losses that result from SFAS No. 133, "Accounting for Derivative Instruments and Hedging Activities," on derivatives that do not qualify for "hedge treatment," as well as on derivatives that do qualify but are in part ineffective because they are not perfect hedges, we focus on the long-term economic effectiveness of those instruments relative to the underlying hedged item and isolate the effects of interest rate volatility, changing credit spreads and changes in our stock price on the fair value of such instruments during the period. Under GAAP, the effects of these factors on the fair value of the derivative instruments (but not on the underlying hedged item) tend to show more volatility in the short term. While our presentation of our results on a Managed Basis provides important information regarding the performance of our Managed portfolio, a limitation of this presentation is that we are presenting the ongoing spread income on loans that have been sold to a trust managed by us. While we believe that our Managed Basis presentation presents the economic substance of our Managed loan portfolio, it understates earnings volatility from securitization gains. Our "Core Earnings" results exclude certain Floor Income, which is real cash income, from our reported results and therefore may understate earnings in certain periods. Management's financial planning and valuation of operating results, however, does not take into account Floor Income because of its inherent uncertainty, except when it is economically hedged through Floor Income Contracts.

11

Pre-Tax Differences between "Core Earnings" and GAAP

        Our "Core Earnings" are the primary financial performance measures used by management to evaluate performance and to allocate resources. Accordingly, financial information is reported to management on a "Core Earnings" basis by reportable segment, as these are the measures used regularly by our chief operating decision maker. Our "Core Earnings" are used in developing our financial plans and tracking results, and also in establishing corporate performance targets and determining incentive compensation. Management believes this information provides additional insight into the financial performance of the Company's core business activities. "Core Earnings" reflect only current period adjustments to GAAP, as described in the more detailed discussion of the differences between GAAP and "Core Earnings" that follows, which includes further detail on each specific adjustment required to reconcile our "Core Earnings" segment presentation to our GAAP earnings.

1)

Securitization Accounting: Under GAAP, certain securitization transactions in our Lending operating segment are accounted for as sales of assets. Under "Core Earnings" for the Lending operating segment, we present all securitization transactions on a Managed Basis as long-term non-recourse financings. The upfront "gains" on sale from securitization transactions as well as ongoing "servicing and securitization revenue" presented in accordance with GAAP are excluded from "Core Earnings" and are replaced by the interest income, provisions for loan losses, and interest expense as they are earned or incurred on the securitization loans. We also exclude transactions with our off-balance sheet trusts from "Core Earnings" as they are considered intercompany transactions on a Managed Basis.

2)

Derivative Accounting: "Core Earnings" exclude periodic unrealized gains and losses arising primarily in our Lending business segment, and to a lesser degree in our Corporate and Other business segment, that are caused primarily by the one-sided mark-to-market derivative valuations prescribed by SFAS No. 133 on derivatives that do not qualify for "hedge treatment" under GAAP. Under "Core Earnings," we recognize the economic effect of these hedges, which generally results in any cash paid or received being recognized ratably as an expense or revenue over the hedged item's life. "Core Earnings" also exclude the gain or loss on equity forward contracts that under SFAS No. 133 are required to be accounted for as derivatives and marked-to-market through earnings.

3)

Floor Income: The timing and amount (if any) of Floor Income earned in our Lending operating segment is uncertain and in excess of expected spreads. Therefore, we exclude such income from "Core Earnings" when it is not economically hedged. We employ derivatives, primarily Floor Income Contracts and futures, to economically hedge Floor Income. As discussed above in "Derivative Accounting," these derivatives do not qualify as effective accounting hedges, and therefore, under GAAP, they are marked-to-market through the "gains (losses) on derivative and hedging activities, net" line on the income statement with no offsetting gain or loss recorded for the economically hedged items. For "Core Earnings," 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)

Acquired Intangibles: We exclude goodwill and intangible impairment and the amortization of acquired intangibles.

12

QuickLinks

SLM CORPORATION Supplemental Earnings Disclosure September 30, 2006 (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 Segment and "Core Earnings" Consolidated Statements of Income (In thousands)
SLM CORPORATION Reconciliation of "Core Earnings" Net Income to GAAP Net Income (In thousands, except per share amounts)