UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 10-K

Commission file numbers 001-13251

SLM CORPORATION
(formerly USA Education, Inc.)
(Exact Name of Registrant as Specified in Its Charter)

(703) 810-3000
(Registrant's Telephone Number, Including Area Code)

Securities registered pursuant to Section 12(b) of the Act:
Common Stock, par value $.20 per share.

Name of Exchange on which Listed:
New York Stock Exchange

6.97% Cumulative Redeemable Preferred Stock, Series A, par value $.20 per share

Name of Exchange on which Listed:
New York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act:
None.

        Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý    No o

        Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Act). Yes ý    No o

        The aggregate market value of voting stock held by non-affiliates of the registrant as of June 28, 2002 was approximately $14,802,593,807 (based on closing sale price of $96.90 per share as reported for the New York Stock Exchange—Composite Transactions).

        As of February 27, 2004, there were 442,536,880 shares of Common Stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

        Portions of the Proxy Statement relating to the registrant's Annual Meeting of Shareholders scheduled to be held May 13, 2004 are incorporated by reference into Part III of this Report.

        Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ý

        This report contains forward-looking statements and information that are based on management's current expectations as of the date of this document. When used in this report, the words "anticipate," "believe," "estimate," "intend" and "expect" and similar expressions are intended to identify forward-looking statements. These forward-looking statements are subject to risks, uncertainties, assumptions and other factors that may cause the actual results to be materially different from those reflected in such forward-looking statements. These 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 these laws and regulations, which may reduce the volume, average term and costs of yields on student loans under the Federal Family Education Loan Program ("FFELP") or result in loans being originated or refinanced under non-FFELP programs or may affect the terms upon which banks and others agree to sell FFELP loans to SLM Corporation and its subsidiaries ("the Company"). The Company could also be affected by changes in the demand for educational financing or in financing preferences of lenders, educational institutions, students and their families; changes in the general interest rate environment and in the securitization markets for education loans, which may increase the costs or limit the availability of financings necessary to initiate, purchase or carry education loans; losses from loan defaults; and changes in prepayment rates and credit spreads.

GLOSSARY

        Listed below are definitions of key terms that are used throughout this document. See also Appendix B for a further discussion of the FFELP.

Consolidation Loans—Under the FFELP, borrowers with eligible student loans may consolidate them into one note with one lender and convert the variable interest rates on the loans being consolidated into a fixed rate for the life of the loan. The new note is considered a Consolidation Loan. Typically a borrower can consolidate their student loans only once unless the borrower has another eligible loan with which to consolidate with the existing Consolidation Loan. The borrower rate on a Consolidation Loan is fixed for the term of the loan and is set by the weighted-average interest rate of the loans being consolidated, rounded up to the nearest 1/8^th of a percent, not to exceed 8.25 percent. In low interest rate environments, Consolidation Loans provide an attractive refinancing opportunity because they allow borrowers to consolidate variable rate loans into a long-term fixed rate loan.

Consolidation Loan Rebate Fee—All holders of Consolidation Loans are required to pay to the U.S. Department of Education an annual 105 basis point Consolidation Loan Rebate Fee on all outstanding principal and accrued interest balances of Consolidation Loans purchased or originated after October 1, 1993, except for loans for which consolidation applications were received between October 1, 1998 and January 31, 1999, where the Consolidation Loan Rebate Fee is 62 basis points.

Constant Prepayment Rate ("CPR")—A variable in life of loan estimates that measures the rate at which loans in the portfolio pay before their stated maturity. The CPR has a direct effect on the average life of the portfolio.

DOE—The U.S. Department of Education.

Direct Loans—Student loans originated directly by the DOE under the William D. Ford Federal Direct Student Loan Program.

Embedded Floor Income—Embedded Floor Income is Floor Income (see definition below) that is earned on off-balance sheet student loans that are in securitization trusts sponsored by us. At the time of the securitization, the option value of Embedded Fixed Rate Floor Income is included in the initial calculation of the Residual Interest and the gain or loss on sale of the student loans. Embedded Floor Income is also included in the quarterly fair value adjustments of the Residual Interest.

2

Fixed Rate Floor Income—We refer to Floor Income associated with student loans whose borrower rate is fixed to term (primarily Consolidation Loans) as Fixed Rate Floor Income.

Floor Income—Our portfolio of FFELP student loans generally earns interest at the higher of a floating rate based on the Special Allowance Payment or SAP (see definition below) formula set by the DOE and the borrower rate, which is fixed over a period of time. We generally finance our student loan portfolio with floating rate debt over all interest rate levels. In low and/or declining interest rate environments, when our student loans are earning at the fixed borrower rate and the interest on our floating rate debt is continuing to decline, we may earn additional spread income and refer to it as Floor Income. Depending on the type of the student loan and when it was originated, the borrower rate is either fixed to term or is reset to a market rate each July 1. As a result, for loans where the borrower rate is fixed to term, we may earn Floor Income for an extended period of time, and for those loans where the borrower interest rate is reset annually on July 1, we may earn Floor Income to the next reset date.

        The following example shows the mechanics of Floor Income for a fixed rate Consolidation Loan:

        Based on this example, if the quarterly average 91-day Treasury bill rate is over 5.15 percent, special allowance payments will be made to ensure that the holder receives at least a specified floating rate based on the Special Allowance Payment formula. On the other hand, if the quarterly average 91-day Treasury bill is below 5.15 percent, the loan holder will earn the minimum floor rate of 8.25 percent from the student loan. The difference between the minimum floor rate of 8.25 percent and the lender's expected yield (i.e., the yield that the lender would have earned if the borrower's rate did not create a floor) is referred to as Floor Income. Because the student loan assets are generally funded with floating rate debt, the net interest income is enhanced during periods of declining interest rates when the student loan is earning at the fixed borrower rate.

Graphic Depiction of Floor Income:

FFELP—The Federal Family Education Loan Program, formerly the Guaranteed Student Loan Program.

3

FDLP—The William D. Ford Federal Direct Student Loan Program.

Floor Income Contracts—We enter into contracts with counterparties under which, in exchange for an upfront fee representing the present value of the Floor Income that we expect to earn on a notional amount of student loans being hedged, we will pay the counterparties the Floor Income earned on that notional amount of student loans over the life of the Floor Income Contract. Specifically, we agree to pay the counterparty the difference, if positive, between the fixed borrower rate less the SAP spread and the average of the applicable interest rate index on that notional amount of student loans for a portion of the estimated life of the student loan. This contract effectively locks in the amount of Floor Income we will earn over the period of the contract. Floor Income Contracts are not considered effective hedges under Statement of Financial Accounting Standards ("SFAS") No. 133, "Accounting for Derivative Instruments and Hedging Activities," and each quarter we must record the change in fair value of these contracts through income.

GSE—The Student Loan Marketing Association is a federally chartered government sponsored enterprise and wholly owned subsidiary of SLM Corporation.

HEA—The Higher Education Act of 1965, as amended.

Managed Basis—We generally analyze the performance of our student loan portfolio on a Managed Basis, under which we view both on-balance sheet student loans and off-balance sheet student loans owned by the securitization trusts as a single portfolio and the related on-balance sheet financings are combined with off-balance sheet debt. When the term Managed is capitalized in this document, it is referring to Managed Basis.

Offset Fee—We are required to pay to the DOE an annual 30 basis point Offset Fee on the outstanding balance of Stafford and PLUS student loans purchased and held by the GSE after August 10, 1993. The fee does not apply to student loans sold to securitized trusts or to loans held outside of the GSE.

Preferred Channel Originations—Preferred Channel Originations are comprised of: 1) student loans that are originated or serviced on our proprietary platforms, and are committed for sale to Sallie Mae, such that we either own them from inception or acquire them soon after origination, and 2) loans that are originated and serviced on other platforms on behalf of Sallie Mae owned brands and our lending partners, Bank One and JP Morgan Chase, and are committed for sale to Sallie Mae.

Preferred Lender List—To streamline the student loan process, most higher education institutions select a small number of lenders to recommend to their students and parents. This recommended list is referred to as the Preferred Lender List.

Private Credit Student Loans—Education loans to students or parents of students that are not guaranteed or reinsured under the FFELP or any other federal student loan program. Private Credit Student Loans include loans for traditional higher education with repayment terms that begin after graduation, similar to the FFELP, and for alternative education, such as career training, that require repayment immediately.

Privatization Act—The Student Loan Marketing Association Reorganization Act of 1996.

Residual Interest—When we securitize student loans, we retain the right to receive cash flows from the student loans sold in excess of amounts needed to pay servicing and other fees and the principal and interest on the bonds backed by the student loans. The Residual Interest is the present value of the future expected cash flows from off-balance sheet student loans in securitized trusts, which includes the present value of Embedded Fixed Rate Floor Income described above. We value the Residual Interest at the time of sale and at each subsequent quarter.

4

Retained Interest—In our securitizations the Retained Interest includes the Residual Interest plus reserve and other cash accounts that serve as credit enhancements to asset-backed securities issued in our securitizations.

Risk Sharing—When a FFELP loan defaults, the federal government guarantees 98 percent of the principal balance plus accrued interest and the holder of the loan must absorb the two percent not guaranteed as a Risk Sharing loss on the loan. All FFELP student loans acquired after October 1, 1993 are subject to Risk Sharing on loan default claim payments unless the default results from death, disability or bankruptcy.

Special Allowance Payment ("SAP")—FFELP student loans generally earn interest at the greater of the borrower rate or a floating rate determined by reference to the average of the applicable floating rates (91-day Treasury bill rate or commercial paper) in a calendar quarter, plus a fixed spread that is dependent upon when the loan was originated and the loan's repayment status. If the resulting floating rate exceeds the borrower rate, the DOE pays the difference directly to us. This payment is referred to as the Special Allowance Payment or SAP and the formula used to determine the floating rate is the SAP formula. We refer to the fixed spread to the underlying index as the Special Allowance margin.

Title IV Programs and Title IV Loans—Student loan programs created under Title IV of the HEA, including the FFELP and the FDLP, and student loans originated under those programs, respectively.

Wind-Down—The dissolution of the Student Loan Marketing Association (the "GSE") under the terms of the Privatization Act.

Wind-Down Period—The period during which the Student Loan Marketing Association is dissolved under the terms of the Privatization Act.

Variable Rate Floor Income—For student loans whose borrower interest rate resets annually on July 1, we may earn Floor Income or Embedded Floor Income based on a calculation of the difference between the borrower rate and the then current interest rate. We refer to this as Variable Rate Floor Income because we may only earn Floor Income through the next reset date.

5

PART I.

Item 1. Business

Introduction to SLM Corporation

        SLM Corporation, more commonly known as Sallie Mae, is the market leader in education finance. We were formed 30 years ago as a federally chartered government-sponsored enterprise with the goal of furthering access to higher education by acting as a secondary market for student loans. Today, Sallie Mae is nearing the completion of a historic privatization process that began in 1997. We now provide a comprehensive array of credit products and related services to the higher education community. These include:

•

FFELP and Private Credit Student Loans,



•

student loan and guarantor servicing, and



•

debt management and collection services.

        We participate in all phases of the student loan process by holding and servicing the loan—from origination and guarantee, through collection, and in some cases, post-default collection. We believe that what distinguishes us from our competition is the breadth and sophistication of the products and services we offer to colleges, universities and students. These include the streamlining of the financial aid process through university-branded web sites, call centers and other solutions that permit financial aid officers to spend more time working with students. Our products and services provide significant cost savings for schools, create time-saving efficiencies for financial aid offices and, in some cases, generate revenues for schools.

        Our earnings growth is fueled largely by the growth in the Managed student loan portfolio and in our fee-based business lines, coupled with cost-effective financing and operating expense control.

        We generate the majority of our earnings from the spread between the yield we receive on our managed portfolio of student loans, and the cost of funding these loans. This spread income is reported on our income statement as "net interest income" for on-balance sheet loans, and "gains on student loan securitizations" and "servicing and securitization revenue" for off-balance sheet loans. We also earn fees from student loan servicing, guarantee processing, and default management and collections services, and incur servicing, selling and administrative expenses in providing these products and services.

        In 2003, we made substantial progress in the Wind-Down of the Student Loan Marketing Association, our government-sponsored enterprise ("GSE") subsidiary. As of December 31, 2003, 78 percent of our Managed student loans were financed outside of the GSE.

        Sallie Mae has more than 7,500 employees nationwide.

Student Lending Marketplace

Overview

        The student loan marketplace consists of federally guaranteed student loans administered by the DOE and Private Credit Student Loans issued by various private sector lenders. There are two competing programs that provide student loans where the ultimate credit risk lies with the federal government: the FFELP and the FDLP. FFELP loans are provided by private sector institutions and are ultimately guaranteed by the DOE. FDLP loans are funded by the taxpayer and provided to borrowers directly by the DOE on terms similar to student loans in the FFELP. In addition to these government guaranteed programs, Private Credit Student Loans are made by financial institutions where the lender assumes the credit risk.

6

        For the federal fiscal year ("FFY") ended September 30, 2003, the DOE estimated that the FFELP's market share in federally guaranteed student loans was 75 percent, up from 73 percent in 2002. (See "Business—Competition.") Total FFELP and FDLP volume for FFY 2003 grew by 16 percent, with the FFELP portion growing 18 percent. Current industry trends indicate that federal student loan market growth will continue at 11 to 12 percent annually over the next few years.

        The HEA includes regulations that cover every aspect of the servicing of a student loan, including communications with borrowers, loan originations and default aversion. Failure to service a student loan properly could jeopardize the 98 percent guarantee on these federal student loans.

        FFELP student loans must be guaranteed by state or non-profit agencies called guarantors. Guarantors are responsible for performing certain functions necessary to ensure the program's soundness and accountability. These functions include reviewing loan application data to detect and prevent fraud and abuse and to assist lenders in preventing default by providing counseling to borrowers. Generally, the guarantor is responsible for ensuring that loans are being serviced in compliance with the requirements of the HEA. When a borrower defaults on a FFELP loan, we submit a claim form to the guarantor who pays us, in most cases, 98 percent of the principal and accrued interest (See "Appendix B" to this document for a more complete description of the role of guarantors).

Drivers of Growth in the Student Loan Industry

        The growth in our Managed student loan portfolio, which includes both on and off-balance sheet student loans, is driven by the growth in the overall student loan marketplace, which has grown due to rising enrollment and college costs, as well as by our own modest market share gains. The size of the federally insured student loan market has more than doubled over the last ten years with student loan originations growing from $24 billion in FFY 1994 to $52 billion in FFY 2003.

        According to the College Board, tuition and fees at four-year public institutions and four-year private institutions have increased 47 percent and 42 percent, respectively, in constant, inflation adjusted dollars, since the 1993-1994 academic year ("AY"). Under the FFELP, there are limits to the amount students can borrow each academic year. Loan limits have not changed since 1992. As a result, more students are turning to Private Credit Student Loans to meet an increasing portion of their education financing needs. Loans—both federal and private—as a percentage of total student aid has increased in AY 2002-03 to 54 percent compared to 47 percent of total student aid in AY 1992-93.

        The DOE predicts that the college-age population will increase 11 to 13 percent by 2013. Demand for education credit will also increase due to the rise in non-traditional students (those not attending college directly from high school) and adult education. In fact, loan volume to the for-profit school

7

sector more than doubled between 1997 and 2002. The following charts show the projected enrollment and average tuition and fee growth for four-year public and private colleges and universities.

Sallie Mae's Loan Origination Model

        We manage the largest portfolio of FFELP student loans, serving more than 7 million borrowers through our ownership and management of $89 billion in student loans, of which $80 billion or 91 percent are federally insured. We also serve a diverse range of clients that includes over 7,000 educational and financial institutions and state agencies. We are the largest servicer of FFELP student loans.

        Our primary marketing point-of-contact is the school's financial aid office where we focus on delivering flexible and cost-effective products to the school and its students. Our sales force, which works with financial aid administrators every day, is the largest in the industry and currently markets the following lender brands: Academic Management Services Corp. ("AMS"), Bank One, JP Morgan Chase, Nellie Mae, Sallie Mae Educational Trust, SLM Financial, and Student Loan Funding Resources ("SLFR"). We also actively market the loan guarantee of United Student Aid Funds, Inc. ("USA Funds") through a separate sales force.

        We acquire student loans from three sources:

•

our Preferred Channel,



•

forward purchase commitments, in which we purchase student loans that are originated on other platforms from various lenders and that are committed by contract to be sold to us, and



•

spot market purchases, which are made by competitive bid.

        Over the past several years we have successfully changed our business model from a wholesale purchaser of loans on the secondary market, to a retail model where we control the front-end origination process. This provides us with higher yielding loans that have a longer duration because we originate or purchase them at or immediately after disbursement. The key measure of this successful transition is the growth in our Preferred Channel Originations, which accounted for 80 percent of Managed student loan acquisitions in 2003. These are our most valuable loans because they cost the least to acquire and remain in our portfolio the longest. In 2003, we originated $15.2 billion in student

8

loans through our Preferred Channel, of which a total of $4.2 billion or 28 percent was originated through our owned brands, $6.2 billion or 41 percent, was originated through our largest lending partners, Bank One and JP Morgan Chase, and $4.8 billion or 31 percent was originated through other lender partners. Under our arrangement with Bank One, we are the bank's exclusive marketing and student loan origination agent. Under a renewable, multi-year agreement, we service and purchase a significant share of Bank One's volume. In 2003, our relationship with Bank One resulted in $3.5 billion in origination volume. We purchase all student loans originated by JP Morgan Chase and this arrangement resulted in $2.7 billion in origination volume in 2003. In January 2004, Bank One and JP Morgan Chase announced their intent to merge. Our agreements with Bank One and JP Morgan Chase are structured such that one or both will remain in place if the merger is consummated. We plan to work with representatives of the banks to ensure that our lending partner relationship remains a vital part of our respective businesses.

        Our Preferred Channel Originations growth has been fueled by both FDLP and new school conversions, and same school sales growth. Since 1999, we have partnered with over 90 schools who have chosen to return to the FFELP from the FDLP. These schools represent over $2.4 billion in market volume. Our FFELP originations at these schools totaled over $1 billion in 2003. In addition to winning new schools, we have also forged broader relationships with many of our existing school clients.

        In 2003, the 20 percent of Managed student loans acquired outside of our Preferred Channel was through Consolidation Loans from third parties (13 percent), spot purchases (5 percent) and other forward purchase commitments (2 percent), respectively.

        In November 2003, we completed the purchase of AMS, the 14th largest FFELP lender in FFY 2002. AMS is also the leading provider of tuition payment plans, with more than 550 colleges and universities using AMS's products. AMS has developed strong relationships with schools' bursars and business offices. By preserving their brand identity and integrating it with Sallie Mae's other key brands, products and services, we expect that this acquisition will contribute to the growth of our Preferred Channel Originations.

        Over the past two years, we have seen a surge in consolidation activity as a result of historically low interest rates. We have made a substantial investment in consolidation marketing to protect our asset base and grow our portfolio, including targeted direct mail campaigns and web-based initiatives for borrowers. Our run-off of FFELP loans for 2003 from consolidation activity to third parties over FFELP loans acquired was $84 million, compared to net FFELP loan run-off of $421 million in 2002. During 2003, $8.6 billion of our Managed loan portfolio consolidated, which has contributed to the changing composition and profitability of our student loan portfolio. Consolidation Loans now represent over 40 percent of our federally guaranteed student loan portfolio. We continue to aggressively focus on loan consolidation in an effort to gain net new consolidation business.

Private Credit Student Loan Programs

        In addition to federal loan programs, which have statutory limits on annual and total borrowing, we offer a variety of Private Credit Student Loan programs to bridge the gap between the cost of education and a student's resources. Over the last several years, tuition has increased faster than federal student aid, resulting in the accelerated growth of Private Credit Student Loans. We offer a number of higher education Private Credit Student Loans that are used by borrowers to bridge the gap between the cost of higher education and the amount financed through capped FFELP loans and the borrowers' resources.

        Through SLM Financial, a wholly owned subsidiary of SLM Corporation, we have substantially expanded our Private Credit Student Loan products to include loans that finance the needs of students in career training and lifelong learning programs. For instance, we offer career training loans to

9

students attending technical and trade schools and other adult learning centers. At December 31, 2003, we had $1.3 billion of career training loans outstanding.

        Since we bear the full credit risk for Private Credit Student Loans, they are underwritten and priced according to credit risk based upon standardized consumer credit scoring criteria. In addition, we provide price and eligibility incentives for students to obtain a credit-worthy co-borrower. Approximately 47 percent of our Private Credit Student Loans have a co-borrower. Finally, where possible, the borrower receives a single bill for both the federally guaranteed and privately underwritten loan. (See also "MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS—CRITICAL ACCOUNTING POLICIES AND ESTIMATES—Provision for Loan Losses.")

Other Products and Services

        We believe that our success in growing our loan origination volume is due to our full service suite of products and services, our high-quality sales team, and the campus relationships we have established. We provide college financial aid offices and students with comprehensive financing solutions that streamline the financial aid process. Our products enable the loan delivery process to be completed on-line within 24 hours. Our goal is to help the financial aid office implement office automation tools and web-based solutions to help them reduce operating costs and focus on counseling students.

        We were the first to provide schools with an Internet-based loan delivery system. We are continuing that technological leadership with the introduction of OpenNet^SM, our newest web-based origination platform, which gives our customers the flexibility to work with multiple lenders yet do all of their processing on one system. OpenNet allows the student to apply for a loan on-line, access private and FFELP applications in one place, and complete the process using E-signature. The system also receives updates from the guarantor in real time and sends automatic certification e-mails to the borrower. The financial aid office can use OpenNet to manage its student loan files, run queries, update and edit records, and take advantage of many other features.

        We are in the process of transitioning our existing web loan delivery platforms, Laureate® and NetWizard^SM, to OpenNet. Over 250 schools are currently using OpenNet.

        We have other web-based systems that help students, parents and the college manage the financial aid process. Among them are:

•

Net.Pay^SM—An electronic bill presentment and payment product for departments on campus to collect payments for tuition, student loans and other bills on-line.



•

Manage Your Loans^SM—a password-protected web site that provides borrowers with 24-hour access to their Sallie Mae-serviced loans.



•

eFAO^SM—An "electronic financial aid office" that gives financial aid administrators on-line tools to organize and communicate financial aid information and resources to students and their families.



•

Your Electronic Award^SM—A school-based web tool that simplifies the financial aid process by replacing the traditional paper award with a highly customized, interactive award that can include links to other funding sources and applications.

        An added benefit of many of our web-based products and services is that they help us reduce our operating costs by eliminating postage costs and automating processes that were previously done manually.

10

Guarantor Services

        We earn fees for providing a full complement of administrative services to FFELP guarantors. FFELP student loans are guaranteed by these agencies, with the DOE providing reinsurance to the guarantor.

        The guarantors are non-profit institutions or state agencies that, in addition to providing the primary guarantee on FFELP loans, are responsible for the following:

•

guarantee issuance—initial approval of loan terms and guarantee eligibility,



•

account maintenance—maintaining and updating records on guaranteed loans,



•

default aversion—assisting lenders in preventing default by delinquent borrowers,



•

collection—post-default loan administration and collections, and



•

guarantee fulfillment—review and processing of guarantee claims.

(See "Guarantor Funding" in the Appendix B for details of the fees paid to guarantors.)

        Currently, we provide a variety of these services to 10 guarantors. Our largest client, USA Funds, is the nation's largest guarantor. In 2003, we processed $9.9 billion in new FFELP loan guarantees for USA Funds and $3.0 billion for our other guarantor servicing customers. This represented 25 percent of the FFELP and FDLP loan market. All of these customers use our proprietary, internally developed guarantee processing system, EAGLE™. EAGLE tracks all guarantee-related activities from the front-end (loan approval, origination and account maintenance) to the back-end (default aversion, collections and federal reporting). We perform most of the transaction processing ourselves, but in some cases we license the EAGLE system to guarantor clients who perform their own transaction processing. Guarantor servicing revenue, which included guaranty issuance and account maintenance fees, was $128 million for 2003.

Default Management Operations and Collections

        We provide defaulted student loan portfolio management services, defaulted student loan collections services and default aversion services through four operating units that comprise our Debt Management Operations group:

•

Portfolio Management,



•

General Revenue Corporation ("GRC"),



•

Pioneer Credit Recovery, Inc. ("PCR"), and



•

Student Assistance Corporation ("SAC").

        Through our Portfolio Management group, we manage the defaulted student loan portfolios for five FFELP guarantors, representing approximately 25 percent of defaulted student loan portfolios held by FFELP guarantors. GRC and PCR provide Title IV loan collections services for guarantors and the DOE, representing approximately 14 percent of the market for such services. In addition, GRC and PCR have contracts with more than 700 colleges and universities to attempt collections of delinquent student loans from various campus-based programs, including Perkins Loans. Our Debt Management Operations group also provides default aversion services through SAC for four guarantors, including the nation's largest, USA Funds.

        In addition, through our Debt Management Operations group, we provide collections services for large federal agencies, credit card clients and other holders of consumer debt. Total fee revenue associated with our Debt Management Operations group for 2003 was $259 million.

11

Financing

        We currently fund our operations primarily through the sale of SLM Corporation ("SLM") debt securities, SLM student loan asset-backed securities and GSE debt securities. We issue all of these in both the domestic and overseas capital markets using both public offerings and private placements. The major objective when financing our business is to minimize interest rate risk through match funding of our assets and liabilities. Generally, on a pooled basis to the extent practicable, we match the interest rate and reset characteristics of our managed assets and liabilities. In this process, we use derivative financial instruments extensively to reduce our interest rate and foreign currency exposure. Interest rate risk management helps us to achieve a stable student loan spread irrespective of the interest rate environment and to offset pressure from adverse legislative changes, changes in asset mix and other interest exposures. We continuously look for ways to minimize funding costs to maintain our student loan spread. We are expanding and diversifying our pool of investors by establishing debt programs in multiple markets that appeal to varied investor bases and by educating potential investors about our business. Finally, we take appropriate steps to ensure sufficient liquidity by financing in multiple markets, which include the institutional, retail, floating rate, fixed rate, unsecured, asset-backed, domestic and international markets.

        Another important objective is to refinance GSE debt with non-GSE debt to meet the timetable of our GSE Wind-Down. Under the Privatization Act, the GSE may issue debt with maturity dates through September 30, 2008 to fund student loan and other permitted asset purchases; however, we plan to complete the GSE's dissolution by June 30, 2006 or earlier with any remaining GSE debt obligations being defeased at that time. As of December 31, 2003, we funded 78 percent of our Managed student loans with non-GSE sources, principally through securitizations. Securitization is and will continue to be our principal source of non-GSE financing, and over time, we expect 70 percent of our annual funding needs will be satisfied by securitizing our loan assets and issuing asset-backed securities.

Competition

        Student Loan Originations and Acquisitions—Our primary competitor for federally guaranteed student loans is the FDLP, which in its first four years of existence (FFYs 1994-1997) grew market share from 4 percent to 34 percent. The FDLP market share peaked at 34 percent but has steadily declined since its peak in 1997 to a 25 percent share in 2003 for the total federally sponsored student loan market. In FFY 2003, FDLP student loans represented 25 percent, or $13.2 billion, of the total federally guaranteed student loan market. We also face competition from a variety of financial institutions including banks, thrifts and state-supported secondary markets. Sallie Mae's 2003 Preferred Channel FFELP originations totaled $12.0 billion, representing a 23 percent market share.

        The rising cost of education has led students and their parents to seek additional private credit sources to finance their education. Private Credit Student Loans are often packaged as supplemental or companion products to FFELP loans and priced competitively to provide additional value for our school relationships.

        In the FFELP marketplace, we are seeing increased use of discounts and borrower benefits, as well as heightened interest in the school-as-lender model in which graduate and professional schools make FFELP student loans directly to eligible borrowers. According to the DOE, 54 institutions used the school-as-lender model for FFY 2003, with total school-as-lender volume of $1.5 billion.

        Guarantor Servicing and Debt Management—Our primary non-profit competitors in guarantor servicing are state and non-profit guarantee agencies that provide third party outsourcing to other guarantors. Our primary for-profit competitor is GuaranTec, LLP, an outsourcing company that is a subsidiary of Nelnet, Inc.

12

        In contrast, the private sector collections industry is highly fragmented with few large public companies and a large number of small scale privately held companies. The collections industry segment that provides third party collections services for the DOE, guarantors and other federal level holders of defaulted debt is highly competitive.

Privatization

        The GSE was established in 1972 as a for-profit corporation under an Act of Congress for the purpose of creating a national secondary market in federal student loans. Having accomplished our original mission and with the creation of a federal competitor, the FDLP, we obtained congressional and shareholder approval to transform from the GSE to a private sector corporation. As a result, SLM Corporation was formed as a Delaware corporation in 1997. To complete this "privatization," we plan to wind down the operations of the GSE by June 2006 and are on track to complete the Wind-Down at an even earlier date. During the period in which we wind down the GSE's operations, which we refer to as the Wind-Down Period, we will not issue new GSE debt obligations that mature after the expected Wind-Down date. We have not issued any long-term GSE debt since July 2003. We have transferred personnel and certain assets of the GSE to SLM Corporation or other non-GSE affiliates and will continue such transfers until the privatization is complete. During the Wind-Down Period, GSE operations have been managed under arm's-length service agreements between the GSE and one or more of its non-GSE affiliates.

        During the course of developing the Wind-Down plan, management was advised by its tax counsel that, while the matter is not certain, under current authority, the defeasance of certain GSE bonds that mature after the dissolution of the GSE, could be construed to be a taxable event for taxable holders of those bonds. Management intends to commence discussions on this matter with the Internal Revenue Service and may seek a private letter ruling that the defeasance does not trigger a taxable event for such bondholders in the context of the GSE's privatization.

        The principal benefit of shedding our GSE status is the ability to originate student loans directly, reducing our dependence on other student loan originators. Privatization has also facilitated our entry into other credit and fee-based businesses within and beyond the student loan industry. The principal cost of privatization is the elimination of our access to the federal agency funding market, and lower cost funding through the implicit guarantee of the federal government. Much of the GSE funding advantage was eroded in 1993 with the imposition of the Offset Fee on a portion of our student loan portfolio. To accomplish privatization, we have been reducing the GSE's liabilities and refinancing the GSE's assets through securitizations and holding company borrowings, and gradually funding new assets outside the GSE. The Offset Fee does not apply to Consolidation Loans, Private Credit Student Loans or FFELP loans held outside of the GSE, including securitized loans. (See "Appendix A" for separate GSE financial statements.)

Available Information

        Copies of our annual reports on Form 10-K and our quarterly reports on Form 10-Q are available on our website free of charge as soon as reasonably practical after we electronically file such reports with the Securities and Exchange Commission (the "SEC"). Investors and other interested parties can access these reports at www.salliemae.com/investors/corpreports.html. The SEC maintains an Internet site (http://www.sec.gov) that contains periodic and other reports such as annual, quarterly and current reports on Forms 10-K, 10-Q and 8-K, respectively, as well as proxy and information statements regarding SLM Corporation and other companies that file electronically with the SEC.

13

Item 2.    Properties

        The following table lists the principal facilities owned by the Company:

        In December 2003, the Company sold its Reston, Virginia headquarters and now leases approximately 229,000 square feet of that building from the purchaser. The Company is constructing a new headquarters building in Reston, Virginia that has approximately 240,000 square feet of space. The Company expects to move into the new headquarters in August 2004. The Company also leases approximately 71,000 square feet for its debt management and collections center in Summerlin, Nevada. In addition, the Company leases approximately 88,000 square feet of office space in Cincinnati, Ohio for the headquarters and debt management and collections center for General Revenue Corporation. In the first quarter of 2003, the Company entered into a 10-year lease with the Wyoming County Industrial Development Authority with a right of reversion to the Company for the Arcade and Perry, New York facilities. The Company also leases an additional 10,000 square feet in Perry, New York for Pioneer Credit Recovery, Inc.'s debt management and collections business. In addition, net of the space it subleases, the Company leases approximately 6,000 square feet of office space in Washington, D.C. With the exception of the Pennsylvania loan servicing center, none of the Company's facilities is encumbered by a mortgage. The Company believes that its headquarters, loan servicing centers and debt management and collections centers are generally adequate to meet its long-term student loan and new business goals. The Company's principal office is currently located in leased space at 11600 Sallie Mae Drive, Reston, Virginia, 20193.

Item 3.    Legal Proceedings.

        The Company and various affiliates were defendants in a lawsuit brought by College Loan Corporation ("CLC") in the United States District Court for the Eastern District of Virginia alleging various breach of contract and common law tort claims in connection with CLC's consolidation loan activities. The Complaint sought compensatory damages of at least $60,000,000.

        On June 25, 2003, after five days of trial, the jury returned a verdict in favor of the Company on all counts. CLC has since filed an appeal. All appellate briefing has been completed and oral argument has been tentatively scheduled for May 2004.

        The Company was named as a defendant in a putative class action lawsuit brought by three Wisconsin residents on December 20, 2001 in the Superior Court for the District of Columbia. The lawsuit sought to bring a nationwide class action on behalf of all borrowers who allegedly paid "undisclosed improper and excessive" late fees over the past three years. The plaintiffs sought damages of one thousand five hundred dollars per violation plus punitive damages and claimed that the class consisted of 2 million borrowers. In addition, the plaintiffs alleged that the Company charged excessive interest by capitalizing interest quarterly in violation of the promissory note. On February 28, 2003, the Court granted the Company's motion to dismiss the complaint in its entirety. The plaintiffs appealed

14

the trial court decision. All appellate briefing has been completed and we expect oral argument to be held in June 2004.

        In July 2003, a borrower in California filed a class action complaint against the Company and certain of its affiliates in state court in San Francisco in connection with a monthly payment amortization error discovered by the Company in the fourth quarter of 2002 (see "MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS—OTHER RELATED EVENTS AND INFORMATION"). The complaint asserts claims under the California Business and Professions Code and other California statutory provisions. The complaint further seeks certain injunctive relief and restitution.

        The Company, together with a number of other FFELP industry participants, filed a lawsuit challenging the DOE's interpretation of and non-compliance with provisions in the HEA governing origination fees and repayment incentives on loans made under the FDLP, as well as interest rates for Direct Consolidation Loans. The lawsuit, which was filed November 3, 2000 in the United States District Court for the District of Columbia, alleges that the Department's interpretations of and non-compliance with these statutory provisions are contrary to the statute's unambiguous text, and are arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law, and violate both the HEA and the Administrative Procedure Act. The Company and the other plaintiffs and the DOE have filed cross-motions for summary judgment. The Court has not ruled on these motions.

        The Company continues to cooperate with the SEC concerning an informal investigation that the SEC initiated on January 14, 2004. The investigation concerns certain year-end accounting entries made by employees of one of the Company's debt collection agency subsidiaries. The Company's Audit Committee has engaged outside counsel to investigate the matter and management has conducted its own investigation. Based on these investigations, the amounts in question appear to be less than $100,000.

        We are also subject to various claims, lawsuits and other actions that arise in the normal course of business. Most of these matters are claims by borrowers disputing the manner in which their loans have been processed. Management believes that these claims, lawsuits and other actions will not have a material adverse effect on our business, financial condition or results of operations.

Item 4.    Submission of Matters to a Vote of Security-Holders

        Nothing to report.

15

PART II.

Item 5.    Market for Registrant's Common Equity and Related Stockholder Matters

        The Company's common stock is listed and traded on the New York Stock Exchange under the symbol SLM. The number of holders of record of the Company's common stock as of February 27, 2004 was 531. The following table sets forth the high and low sales prices for the Company's common stock for each full quarterly period within the two most recent fiscal years.

COMMON STOCK PRICES

        The Company paid regular quarterly dividends of $.07 per share on the common stock for the first three quarters of 2002, $.08 for the fourth quarter of 2002 and the first quarter of 2003, $.17 for the last three quarters of 2003, and declared a regular quarterly dividend of $.17 for the first quarter of 2004.

        In May 2003, the Company announced a three-for-one stock split of the Company's common stock to be effected in the form of a stock dividend. The additional shares were distributed on June 20, 2003 for all shareholders of record on June 6, 2003. All share and per share amounts presented have been retroactively restated for the stock split. Stockholders' equity has been restated to give retroactive recognition to the stock split for all periods presented, by reclassifying from additional paid-in capital to common stock, the par value of the additional shares issued as a result of the stock split.

16

Item 6.    Selected Financial Data

Selected Financial Data 1999-2003
(Dollars in millions, except per share amounts)

        The following table sets forth selected financial and other operating information of the Company. The selected financial data in the table is derived from the consolidated financial statements of the Company. The data should be read in conjunction with the consolidated financial statements, related notes, and "MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS" included in this Form 10-K.

17

Item 7.    Management's Discussion and Analysis of Financial Condition and Results of Operations

MANAGEMENT'S DISCUSSION AND ANALYSIS OF
FINANCIAL CONDITION AND RESULTS OF OPERATIONS
Years ended December 31, 2001-2003
(Dollars in millions, except per share amounts)

OVERVIEW

        We are the largest private source of funding, delivery and servicing support for education loans in the United States primarily through our participation in the FFELP. Our primary business is to originate, acquire and hold student loans. We also provide a wide range of financial services, processing capabilities and information technology to meet the needs of educational institutions, lenders, students and their families, and guarantee agencies. We earn fees for student loan servicing, guarantee processing, student loan default management and loan collections. SLM Corporation is a holding company that operates through a number of subsidiaries including the Student Loan Marketing Association, a federally chartered government-sponsored enterprise. References in this annual report to "the Company" refer to SLM Corporation and its subsidiaries.

        We have provided the discussion of the GSE within the context of this "Management's Discussion and Analysis of Financial Condition and Results of Operations" ("MD&A") because the GSE's primary function of financing the initial purchase of student loans is a subset of similar operations conducted by the Company. As we wind down the GSE, such operations will constitute less and less of the Company's operations. MD&A disclosures applicable solely to the GSE are included at the end of this MD&A in the section titled "Student Loan Marketing Association." The discussion that follows regarding our interest income and expenses from on-balance sheet assets and liabilities is applicable to both the Company and the GSE. Likewise, because all of our FFELP securitizations to date have originated from the GSE, the discussion of securitization gains for FFELP student loans is applicable to the GSE only. The ongoing servicing and securitization revenue from those securitizations is primarily earned by the Company because the Retained Interests in FFELP securitizations are sold by the GSE to SLM Corporation shortly after completion of the securitization transaction. Discussions of Private Credit Student Loan securitizations are applicable to the Company only. The discussions of off-balance sheet loans, our fee-based businesses, and our operations on a Managed Basis, as well as the discussions set forth below under the headings "Selected Financial Data," "Other Income," "Federal and State Taxes" and "Alternative Performance Measures" do not involve the GSE and relate to the Company on a consolidated basis.

        In 2003, the majority of our student loan purchases were financed in the GSE and were initially financed through the issuance of short-term GSE debt obligations and then through student loan securitizations that were conducted through the GSE. Once securitized, the GSE no longer owns the student loans and the bonds issued by the trust are not obligations of the GSE. As the Wind-Down of the GSE continues, the liquidity provided to the Company by the GSE is being replaced by non-GSE financing, including securitizations originated by non-GSE subsidiaries of SLM Corporation. All student loans that the Company directly originates are owned by non-GSE subsidiaries from inception.

        The GSE has no employees, so the management of its operations is provided by the Company under a management services agreement. We also service the majority of the GSE's student loans under a servicing agreement between the GSE and Sallie Mae, Inc., a wholly owned non-GSE subsidiary of SLM Corporation which includes the division of Sallie Mae Servicing.

        See "STUDENT LOAN MARKETING ASSOCIATION—Privatization Act—GSE Wind-Down" for a more detailed discussion of the GSE and the progress of the Company's Wind-Down effort.

18

EXECUTIVE SUMMARY

        We have built the Company to be the dominant player in every phase of the student loan life cycle—from origination of the student loans to servicing the student loans to debt management of delinquent and ultimately defaulted student loans. As the leading company in our industry, we are positioned to meet the growing demand for post-secondary education credit across and related services.

        We have used both internal growth and strategic acquisitions to attain this leadership position. We now have the largest and most successful sales force in the industry, which is positioned to deliver our product offerings on campus. The core of our marketing strategy is to promote our on-campus brands, which generate student loan originations through our Preferred Channel. Loans acquired through our Preferred Channel are more profitable than loans acquired through our forward purchase commitments or the spot market since they are acquired earlier in the student loan's life and we generally pay lower premiums to acquire such loans. We have built brand leadership between the Sallie Mae name and those of our leading lender partners, Bank One and JP Morgan Chase, such that we capture the volume of three of the top five originators of FFELP loans. These sales and marketing efforts are supported by the largest and most technologically advanced servicing capabilities in the industry, providing an unmatched array of servicing capability to financial aid offices.

        Demand for post-secondary education in the United States has grown steadily over the last decade and we expect this growth rate to continue in the future. The DOE predicts that the college age population will increase 11 to 13 percent by 2012. Demand for education credit will be further increased by more non-traditional students (those not attending college directly from high school) and adult education. In addition, tuition costs have risen 47 percent for four-year public institutions and 42 percent for four-year private institutions on an inflation-adjusted basis since the 1993-1994 academic year. Management believes that the twin factors of increasing demand for education coupled with rising tuition costs will drive growth in education financing well into the next decade. In 2003, we acquired $20.7 billion of student loans, a 25 percent increase over the $16.5 billion acquired in 2002. Of the student loans acquired, we originated $15.2 billion of student loans through our Preferred Channel, an increase of 23 percent over the $12.4 billion of student loans originated in 2002.

        The main driver of our earnings continues to be our Managed portfolio of student loans, which in 2003, grew by 14 percent to $89 billion at December 31, 2003. FFELP student loans are 98 percent guaranteed by the Federal government and as such represent high quality assets with very little credit risk and predictable earnings streams that are relatively easily financed. At December 31, 2003, our Managed FFELP student loan portfolio was $80.5 billion or 91 percent of total Managed student loans.

        FFELP loan limits have not been raised since 1992, so to meet the increasing cost of higher education, students have had to turn to alternative sources of education financing. A large and growing source of this supplemental education financing is provided through campus-based Private Credit Student Loans, of which we are the largest provider. At December 31, 2003, we owned $8.3 billion of Private Credit Student Loans representing 9 percent of our Managed student loan portfolio. This portfolio grew by 43 percent in 2003.

        Private Credit Student Loans consist of two general types: those that are designed to bridge the gap between the cost of higher education and the amount financed through capped federally insured loans and the borrowers' resources, and those that are used to meet the needs of students in alternative learning programs such as career training, distance learning and lifelong learning programs. Unlike FFELP loans, Private Credit Student Loans are subject to the full credit risk of the borrower. We manage this additional risk through industry tested loan underwriting standards and a combination of higher interest rates and loan origination fees that compensate us for the higher risk. As a result, we earn much higher spreads on Private Credit Student Loans than on FFELP loans. We believe that they are an important driver of future earnings growth.

19

        The growth in the Managed portfolio of student loans will drive future earnings growth only if we maintain the student loan spread earned on those loans. As we continue to wind down the GSE, the cost of funding our Managed student loan portfolio will increase as we replace GSE funding with higher cost non-GSE funding sources. The increased funding costs coupled with the rapid growth in Consolidation Loans puts pressure on our student loan spread. We have actively managed these adverse effects by acquiring a higher percentage of student loans through our Preferred Channel and by the increasing percentage of Private Credit Student Loans in our Managed portfolio. The Managed student loan spread for the years ended December 31, 2003 and 2002, exclusive of Floor Income and changes in estimates, was 2.00 percent and 1.88 percent, respectively. In recent years, the Managed spread has also benefited from Floor Income Contracts.

        While student loans remain the core of our business, we are committed to extending and diversifying our business in higher education related fee-based services, primarily guarantor servicing, debt management services, and loan servicing. For 2003, these businesses generated 26 percent of net revenues (net interest income plus other income on a Managed Basis), up from 8 percent in 1999. In total, the debt management businesses generated gross revenue of $259 million in 2003, an increase of 39 percent from the $186 million earned in 2002, and guarantor servicing fees increased by 21 percent to $128 million in 2003 versus $106 million in 2002. The growth in these businesses has also increased operating expenses at approximately the same rate. We are committed to expanding these businesses further both through internal business development and selective strategic acquisitions.

        Our biggest funding challenge in winding down the GSE is to maintain cost effective liquidity and access to the capital markets as we transition from GSE funding to SLM Corporation non-GSE funding. The main source of non-GSE funding is student loan securitizations and we have built a highly liquid and deep market for such financings as evidenced by the over $30 billion of student loans securitized in sixteen transactions in 2003 versus $13.7 billion in nine transactions in 2002.

        While the growth in our securitizations was very important to the GSE Wind-Down plan, equally as important was the myriad of new unsecured non-GSE short and long-term funding vehicles that we introduced in 2003. We issued almost $15 billion of SLM Corporation, term, non-GSE unsecured debt in 2003 which increased the balance of such debt to $20.3 billion at December 31, 2003, a 187 percent increase over December 31, 2002. This shift in funding was accomplished through the introduction of several new funding programs that further diversified our funding sources and substantially increased our fixed income investor base. We believe that the record volume of non-GSE financing, which, combined with securitization, equaled 2.4 times our student acquisitions in 2003, is indicative of our ability to successfully finance the Company in a post-GSE environment. At December 31, 2003, we financed 78 percent of our Managed student loans with non-GSE sources versus 54 percent at December 31, 2002.

        We face a number of challenges and risks that can materially affect our future results such as changes in:

•

applicable laws and regulations, which may change the volume, average term, effective yields and refinancing options of student loans under the FFELP or provide advantages to competing FEELP and non-FFELP loan providers;



•

demand and competition for education financing;



•

financing preferences of students and their families;



•

borrower default rates on privately insured loans;



•

prepayment rates on student loans, particularly prepayments through loan consolidation;



•

access to the capital markets for non-GSE funding at favorable spreads; and



•

our operating execution and efficiencies, including errors, omissions, and breakdowns in internal control.

20

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

        MD&A discusses our consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States ("GAAP"). The preparation of these financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the reported amounts of income and expenses during the reporting periods. We base our estimates and judgments on historical experience and on various other factors that we believe are reasonable under the circumstances. Actual results may differ from these estimates under varying assumptions or conditions. Note 2 to the consolidated financial statements includes a summary of the significant accounting policies and methods used in the preparation of our consolidated financial statements.

        On an ongoing basis, management evaluates its estimates, particularly those that include the most difficult, subjective or complex judgments and are often about matters that are inherently uncertain. These estimates relate to the following accounting policies that are discussed in more detail below: securitization accounting and Retained Interests, provision for loan losses, and derivative accounting. Also, as part of our regular quarterly evaluation of the critical estimates used by the Company, we have updated a number of estimates to account for the increase in Consolidation Loan activity.

Effects of Consolidation Loan Activity on Estimates

        The combination of aggressive marketing in the student loan industry and low interest rates has led to record levels of Consolidation Loan volume, which, in turn, had a significant effect on a number of accounting estimates. As long as interest rates remain at historically low levels, and absent any changes in the HEA, we expect the Consolidation Loan program to continue to be an attractive option for borrowers. Accordingly, we updated our assumptions that are affected primarily by Consolidation Loan activity and updated the estimates used in developing the cash flows and effective yield calculations as they relate to the amortization of student loan premiums and discounts, borrower benefits, residual interest income and the valuation of the Residual Interest.

        Loan consolidation activity affects each estimate differently depending on whether the original FFELP Stafford loans being consolidated are on or off-balance sheet and whether the resulting Consolidation Loan is retained by us or consolidated with a third party. When we consolidate a FFELP Stafford loan that was in our portfolio, the term of that loan is extended and the term of the amortization is likewise extended to match the new term of the loan. In that process the capitalized acquisition costs (premium) must be adjusted from inception to reflect the new term of the consolidated loan. The following schedule summarizes the impact of loan consolidation on each affected financial statement line item. See also "NET INTEREST INCOME—Student Loans" and "OTHER INCOME—Servicing and Securitization Revenue" for financial results of these changes.

21

Effect of Increasing Consolidation Activity

On-Balance Sheet Student Loans

Off-Balance Sheet Student Loans

* As estimates are updated, the premium balance must be adjusted from inception to reflect the new expected term of the loan.

Consolidation Loans in Securitizations

        The estimate of the CPR also affects the estimate of the average life of securitized trusts and therefore affects the valuation estimate of the Residual Interest. Prepayments shorten the average life of the trust, and if all other factors remain equal, will reduce the value of the Residual Interest asset, the securitization gain on sale and the effective yield used to recognize interest income. Prepayments on student loans in securitized trusts are primarily driven by the rate at which securitized FFELP loans are consolidated. When a loan is consolidated from the trust either by us or a third party, the loan is repurchased from the trust and is treated as a prepayment. In cases where the loan is consolidated by us, it will be recorded as an on-balance sheet asset.

22

Securitization Accounting and Retained Interests

        We regularly engage in securitization transactions as part of our financing strategy. As described in more detail in "OTHER INCOME—Servicing and Securitization Revenue," in a securitization we sell student loans to a trust that issues bonds backed by the student loans as part of the transaction. When our securitizations meet the sale criteria of Statement of Financial Accounting Standards ("SFAS") No. 140, "Accounting for Transfers and Servicing of Financial Assets and Extinguishments of Liabilities—a Replacement of SFAS No. 125," we record a gain on the sale of the student loans which includes using a discounted cash flow analysis to calculate the fair value of the Retained Interest.

        The Retained Interests in each of our securitizations are treated as available-for-sale securities in accordance with SFAS No. 115, "Accounting for Certain Investments in Debt and Equity Securities," and therefore must be marked-to-market with temporary unrealized gains and losses recognized, net of tax, in accumulated other comprehensive income in stockholders' equity. Since there are no quoted market prices for our Retained Interests, we estimate their fair value both initially and each subsequent quarter using the key assumptions listed below:

•

the projected net interest yield from the underlying securitized loans, which can be impacted by the forward yield curve;



•

the calculation of the Embedded Floor Income associated with the securitized loan portfolio (see below);



•

the CPR;



•

the discount rate used to calculate the Residual Interest commensurate with the risks involved; and



•

the expected credit losses from the underlying securitized loan portfolio.

        We earn interest income and periodically evaluate our Retained Interests for other than temporary impairment in accordance with the Emerging Issues Task Force ("EITF") Issue No. 99-20 "Recognition of Interest Income and Impairment on Purchased and Retained Beneficial Interests in Securitized Financial Assets." Under this standard, on a quarterly basis we estimate the cash flows to be received from our Retained Interests and these revised cash flows are used prospectively to calculate a yield for income recognition. In cases where our estimate of future cash flows results in a decrease in the yield used to recognize interest income compared to the prior quarter, the Retained Interest is written down to fair value, first to the extent of any unrealized gain in accumulated other comprehensive income, then through earnings as an other than temporary impairment. These estimates are the same as those used for the valuation of the Residual Interest discussed above.

        We also receive income for servicing the loans in our securitization trusts. We assess the amounts received as compensation for these activities at inception and on an ongoing basis to determine if the amounts received are adequate compensation as defined in SFAS No. 140. To the extent such compensation is determined to be no more or less than adequate compensation, no servicing asset or obligation is recorded.

Provision for Loan Losses

        The provision for loan losses represents the periodic expense of maintaining an allowance sufficient to absorb losses, net of recoveries, inherent in the student loan portfolios. The allowance for Private Credit Student Loan losses is an estimate of losses in the portfolio at the balance sheet date that will be charged off in subsequent periods. We estimate our losses using historical data from our Private Credit Student Loan portfolios, extrapolations of FFELP loan loss data, current trends and relevant industry information. As our Private Credit Student Loan portfolios continue to mature, more reliance is placed on our own historic Private Credit Student Loan charge-off and recovery data.

23

Accordingly, during the fourth quarter, we updated our expected default assumptions to further align the allowance estimate with our collection experience and the terms and policies of the individual Private Credit Student Loan programs. We use this data in internally developed models to estimate the amount of losses, net of subsequent collections, projected to occur in the Private Credit Student Loan portfolios.

        When calculating the Private Credit Student Loan loss reserve, we divide the portfolio into categories of similar risk characteristics based on loan program type, underwriting criteria, existence or absence of a co-borrower, repayment begin date and repayment status. We then apply default and collection rate projections to each category. The repayment begin date indicates when the borrower is required to begin repaying their loan. Our career training Private Credit Student Loan programs (15 percent of the Managed Private Credit Student Loan portfolio at December 31, 2003) generally require the borrowers to start repaying their loan immediately. Our higher education Private Credit Student Loan programs (85 percent of the Managed Private Credit Student Loan portfolio at December 31, 2003) do not require the borrowers to begin repayment until six months after they have graduated or otherwise left school. Consequently, our loss estimates for these programs are minimal while the borrower is in school. At December 31, 2003, 41 percent of the principal balance in the higher education Managed Private Credit Student Loan portfolio relates to borrowers who are still in-school (not required to make payments). As the current portfolio ages, an increasing percentage of the borrowers will leave school and be required to begin payments on their loans. The allowance for losses will change accordingly with the percentage of borrowers in repayment.

        Our loss estimates include losses to be incurred over the loss confirmation period, which is the period of the highest concentration of defaults. The loss confirmation period is two years for career training loans beginning when the loan is originated and five years for higher education loans beginning when the borrower leaves school, similar to the rules governing FFELP payment requirements. Our collection policies allow for periods of nonpayment for borrowers experiencing temporary difficulty meeting payment obligations (typically, very early in the repayment term when they are starting their career). This is referred to as forbearance status (see "NET INTEREST INCOME-Student Loans-Delinquencies"). At December 31, 2003, 6 percent of the Managed Private Credit Student Loan portfolio was in forbearance status. The loss confirmation period is in alignment with our typical collection cycle and considers these periods of nonpayment.

        Private Credit Student Loan principal and accrued interest is charged off against the allowance at 212 days delinquency. Private Credit Student Loans continue to accrue interest until they are charged off and removed from the active portfolio. Recoveries on loans charged off are recorded directly to the allowance.

        Accordingly, the evaluation of the provision for loan losses is inherently subjective as it requires material estimates that may be susceptible to significant changes. Management believes that the allowance for loan losses is adequate to cover probable losses in the student loan portfolio.

Derivative Accounting

        We use interest rate swaps, foreign currency swaps, interest rate futures contracts, Floor Income Contracts and interest rate cap contracts as an integral part of our overall risk management strategy to manage interest rate risk arising from our fixed rate and floating rate financial instruments. We account for these instruments in accordance with SFAS No. 133, "Accounting for Derivative Instruments and Hedging Activities," which requires that every derivative instrument, including certain derivative instruments embedded in other contracts, be recorded at fair value on the balance sheet as either an asset or liability. We determine the fair value for our derivative instruments using pricing models that consider current market values and the contractual terms of the derivative contracts. Pricing models and their underlying assumptions impact the amount and timing of unrealized gains and losses

24

recognized; the use of different pricing models or assumptions could produce different financial results. As a matter of policy, we compare the fair values of our derivatives that we calculate to those provided by our counterparties on a monthly basis. Any significant differences are identified and resolved appropriately.

        We make certain judgments in the application of hedge accounting under SFAS No. 133. The most significant judgment relates to the application of hedge accounting in connection with our forecasted debt issuances. Under SFAS No. 133, if the forecasted transaction is probable to occur then hedge accounting may be applied. We regularly update our probability assessment related to such forecasted debt issuances. This assessment includes analyzing prior debt issuances and assessing changes in our future funding strategies.

        SFAS No. 133 requires that changes in the fair value of derivative instruments be recognized currently in earnings unless specific hedge accounting criteria as specified by SFAS No. 133 are met. We believe that all of our derivatives are effective economic hedges and they are a critical element of our interest rate risk management strategy. However, under SFAS No. 133, some of our derivatives, primarily Floor Income Contracts, Eurodollar futures contracts, certain basis swaps and equity forwards, do not qualify for "hedge treatment" under SFAS No. 133. Therefore, changes in market value along with the periodic net settlements must be recorded through the derivative market value adjustment in the income statement with no consideration for the corresponding change in fair value of the hedged item. The derivative market value adjustment is primarily caused by interest rate volatility and changing credit spreads during the period and the volume and term of derivatives not receiving hedge accounting treatment. See also "EFFECTS OF SFAS NO. 133—Derivative Accounting" for a detailed discussion of our accounting for derivatives.

25

SELECTED FINANCIAL DATA

Condensed Statements of Income

26

Condensed Balance Sheets

RESULTS OF OPERATIONS

NET INTEREST INCOME

        Net interest income is derived largely from our portfolio of student loans that remain on-balance sheet. The "Taxable Equivalent Net Interest Income" analysis below is designed to facilitate a comparison of non-taxable asset yields to taxable yields on a similar basis. Additional information regarding the return on our student loan portfolio is set forth under "Student Loans—Student Loan Spread Analysis." Information regarding the provision for losses is contained in Note 5 to the consolidated financial statements.

27

Taxable Equivalent Net Interest Income

        The amounts in the following table are adjusted for the impact of certain tax-exempt and tax-advantaged investments based on the marginal federal corporate tax rate of 35 percent.

Average Balance Sheets

        The following table reflects the rates earned on interest earning assets and paid on interest bearing liabilities for the years ended December 31, 2003, 2002 and 2001.

28

Rate/Volume Analysis

        The following rate/volume analysis shows the relative contribution of changes in interest rates and asset volumes.

Derivative Reclassification—Non-GAAP

        A recent interpretation of SFAS No. 133 requires net settlement income/expense on derivatives and realized gains/losses related to derivative dispositions that do not qualify as hedges under SFAS No. 133 to be included in the derivative market value adjustment on the income statement. In response to this interpretation, we believe that it is helpful to the understanding of our business to include two presentations of net interest income and net interest margin. The first is a GAAP presentation that includes the net settlement income/expense on derivatives and realized gains/losses in the derivative market value adjustment line and thus does not include these items in net interest income or the net interest margin. The second is a non-GAAP presentation that assumes that these net settlements have been reclassified to the financial statement line item of the economically hedged item, which then includes them in the net interest income and margin. We believe that this second presentation is meaningful and reflects how management manages interest rate risk through the match funding of interest sensitive assets and liabilities. The presentations of our taxable equivalent net interest income, average balance sheet, rate volume analysis, student loan spread and funding costs in the following tables will reflect these reclassifications. The table below details the reclassification of the derivative net settlements and realized gains/losses related to derivative dispositions that is used in the subsequent presentations as discussed above.

29

Taxable Equivalent Net Interest Income After Reclassification—Non-GAAP

        The amounts in the following table are adjusted for the impact of certain tax-exempt and tax-advantaged investments based on the marginal federal corporate tax rate of 35 percent.

Taxable Equivalent Net Interest Income Reconciliation from GAAP to non-GAAP

        The following table reconciles the Taxable Equivalent Net Interest Income from GAAP to non-GAAP.

30

Average Balance Sheets After Reclassification—Non-GAAP

        The following table reflects the rates earned on interest earning assets and paid on interest bearing liabilities for the years ended December 31, 2003, 2002 and 2001.