, 2015

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ABOUT THIS PROSPECTUS SUPPLEMENT

        This prospectus supplement and the accompanying prospectus are part of a "shelf" registration statement that we filed with the SEC. Under this shelf registration process, we may sell the securities described in the accompanying prospectus at our discretion in one or more offerings. You should read (i) this prospectus supplement, (ii) the accompanying prospectus, (iii) any free writing prospectus prepared by or on behalf of us or to which we have referred you and (iv) the documents incorporated by reference herein and therein that are described in this prospectus supplement and the accompanying prospectus under the heading "Where You Can Find More Information."

        We and the Selling Stockholder have not, and the underwriters have not, authorized anyone to provide you with any information other than that contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or any free writing prospectus prepared by or on behalf of us to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may have provided you. We, the Selling Stockholder and the underwriters are offering to sell, and seeking offers to buy, these securities only in jurisdictions where the offers or sales are permitted. You should assume that the information appearing in this prospectus supplement and the accompanying prospectus or any other documents incorporated by reference in either is accurate only as of the stated date of each document in which the information is contained. After the stated date, our business, financial condition, results of operations and prospects may have changed.

        This prospectus supplement and the accompanying prospectus summarize certain documents and other information to which we refer you for a more complete understanding of what we discuss in this prospectus supplement and the accompanying prospectus. In making an investment decision, you should rely on your own examination of our Company (as defined herein) and the terms of this offering and our common stock, including the merits and risks involved.

        We, the Selling Stockholder and the underwriters are not making any representation to any purchaser of our common stock regarding the legality of the purchaser's investment in our common stock. You should not consider any information contained or incorporated by reference in this prospectus supplement or the accompanying prospectus to be legal, business or tax advice. You should consult your own attorney, business advisor and tax advisor for legal, business and tax advice regarding an investment in our common stock.

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Prospectus Supplement

PROSPECTUS

        Certain of the states in which we are licensed to originate loans and the state in which our insurance subsidiaries are domiciled (Indiana) have laws or regulations which require regulatory approval for the acquisition of "control" of regulated entities. Under some state laws or regulations, there exists a presumption of "control" when an acquiring party acquires as little as 10% of the voting securities of a regulated entity or of a company which itself controls (directly or indirectly) a regulated entity (the threshold is 10% under Indiana's insurance statutes). Therefore, any person acquiring 10% or more of our common stock may need the prior approval of some state insurance and/or licensing regulators, or a determination from such regulators that "control" has not been acquired.

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NON-GAAP FINANCIAL MEASURES

        The SEC has adopted rules to regulate the use of "non-GAAP financial measures" in filings with the SEC and in other public disclosures. These measures are derived on the basis of methodologies other than in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP").

        We present pretax core earnings, as described under "Summary—Summary Consolidated Historical and Pro Forma Financial Data," as a non-GAAP financial measure in this prospectus supplement and accompanying prospectus. Pretax core earnings is a key performance measure used by management in evaluating the performance of our Core Consumer Operations. Pretax core earnings represents our income (loss) before provision for (benefit from) income taxes on a historical accounting basis, and excludes results of operations from our non-core portfolio (Real Estate segment) and other non-originating legacy operations, restructuring expenses related to the Consumer and Insurance segment, gains (losses) associated with accelerated long-term debt repayment and repurchases of long-term debt related to Core Consumer Operations (attributable to SHI), gains (losses) on fair value adjustments on debt related to Core Consumer Operations (attributable to SHI), one-time costs associated with debt refinance related to the Consumer and Insurance segment and results of operations related to non-controlling interests. Pretax core earnings is a non-GAAP measure and should be considered in addition to, but not as a substitute for or superior to, operating income, net income, operating cash flow and other measures of financial performance prepared in accordance with U.S. GAAP. See "Summary—Summary Consolidated Historical and Pro Forma Financial Data" in this prospectus supplement for a quantitative reconciliation from income (loss) before provision for (benefit from) income taxes on a historical accounting basis to pretax core earnings.

        We also present our segment financial information on a historical accounting basis (a non-GAAP measure using the same accounting basis that we employed prior to the Fortress Acquisition (as defined under "Summary—Our Corporate History and Corporate Information")). This presentation provides us and other interested third parties a consistent basis to better understand our operating results. This presentation is not in accordance with, or a substitute for, U.S. GAAP and may be different from, or inconsistent with, non-GAAP financial measures used by other companies. See Note 22 of the Notes to Consolidated Financial Statements in our Annual Report on Form 10-K for the year ended December 31, 2014, which is incorporated by reference herein, for reconciliations of segment information on a historical accounting basis to consolidated financial statement amounts.

INDUSTRY AND MARKET DATA

        We obtained the market and competitive position data used throughout this prospectus supplement and accompanying prospectus from our own research, surveys or studies conducted by third parties and industry or general publications. Industry publications and surveys generally state that they have obtained information from sources believed to be reliable, but do not guarantee the accuracy and completeness of such information. While we believe that each of these studies and publications is reliable, neither we nor the underwriters have independently verified such data and neither we nor the underwriters make any representation as to the accuracy of such information. Similarly, we believe our internal research is reliable, but it has not been verified by any independent sources.

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FORWARD-LOOKING STATEMENTS

        This prospectus supplement and the accompanying prospectus and the documents incorporated by reference herein and therein contain or incorporate by reference certain "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 that reflect our current views with respect to, among other things, future events and financial performance. You can identify these forward-looking statements by the use of forward-looking words such as "outlook," "believes," "expects," "potential," "continues," "may," "will," "should," "could," "seeks," "approximately," "predicts," "intends," "plans," "estimates," "anticipates," "target," "projects," "contemplates" or the negative version of those words or other comparable words. Any forward-looking statements contained or incorporated by reference in this prospectus supplement and the accompanying prospectus and the documents incorporated by reference herein and therein are based upon our historical performance and on our current plans, estimates and expectations in light of information currently available to us. Such forward-looking statements are subject to various risks and uncertainties and assumptions relating to our operations, financial results, financial condition, business, prospects, growth strategy and liquidity. Accordingly, there are or will be important factors that could cause our actual results to differ materially from those indicated in these statements. As set forth more fully under "Part I, Item 1A. Risk Factors" in our most recent Annual Report on Form 10-K, which is incorporated by reference herein, factors that could have a material adverse effect on our operations and future prospects include, but are not limited to:

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various risks relating to the Proposed Acquisition, including in respect of the satisfaction of closing conditions to the Proposed Acquisition that are materially adverse to the business, financial condition or results of operations of the combined company;



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unanticipated difficulties financing the purchase price of the Proposed Acquisition;



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unanticipated expenditures relating to the Proposed Acquisition;



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uncertainties as to the timing of the closing of the Proposed Acquisition;



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litigation relating to the Proposed Acquisition;



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the impact of the Proposed Acquisition on each company's relationships with employees and third parties;



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the inability to obtain, or delays in obtaining, cost savings and synergies from the Proposed Acquisition and risks associated with integration of the companies;



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changes in general economic conditions, including the interest rate environment in which we conduct business and the financial markets through which we can access capital and also invest cash flows from our consumer and insurance segment;



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levels of unemployment and personal bankruptcies;



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natural or accidental events such as earthquakes, hurricanes, tornadoes, fires, or floods affecting our customers, collateral, or branches or other operating facilities;



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war, acts of terrorism, riots, civil disruption, pandemics, or other events disrupting business or commerce;



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changes in the rate at which we can collect or potentially sell our finance receivables portfolio;



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the effectiveness of our credit risk scoring models in assessing the risk of customer unwillingness or lack of capacity to repay;



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changes in our ability to attract and retain employees or key executives to support our businesses;

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changes in the competitive environment in which we operate, including the demand for our products, customer responsiveness to our distribution channels, and the strength and ability of our competitors to operate independently or to enter into business combinations that result in a more attractive range of customer products or provide greater financial resources;



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shifts in collateral values, delinquencies, or credit losses;



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changes in federal, state and local laws, regulations, or regulatory policies and practices, including the Dodd-Frank Wall Street Reform and Consumer Protection Act (which, among other things, established the Consumer Financial Protection Bureau, which has broad authority to regulate and examine financial institutions), that affect our ability to conduct business or the manner in which we conduct business, such as licensing requirements, pricing limitations or restrictions on the method of offering products, as well as changes that may result from increased regulatory scrutiny of the sub-prime lending industry;



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potential liability relating to real estate and personal loans which we have sold or may sell in the future, or relating to securitized loans, if it is determined that there was a non-curable breach of a warranty made in connection with such transactions;



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the effect of future sales of our remaining portfolio of real estate loans and the transfer of servicing of these loans;



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the costs and effects of any litigation or governmental inquiries or investigations involving us, particularly those that are determined adversely to us;



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our continued ability to access the capital markets or the sufficiency of our current sources of funds to satisfy our cash flow requirements;



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our ability to comply with our debt covenants;



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our ability to generate sufficient cash to service all of our indebtedness;



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our substantial indebtedness, which could prevent us from meeting our obligations under our debt instruments and limit our ability to react to changes in the economy or our industry, or our ability to incur additional borrowings;



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the potential for downgrade of our debt by rating agencies, which would have a negative impact on our cost of, and access to, capital;



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the impacts of our securitizations and borrowings;



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our ability to maintain sufficient capital levels in our regulated and unregulated subsidiaries;



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changes in accounting standards or tax policies and practices and the application of such new policies and practices to the manner in which we conduct business; and



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the material weakness that we have identified in our internal control over financial reporting.

        The forward-looking statements made or incorporated by reference in this prospectus supplement and the accompanying prospectus and the documents incorporated by reference herein and therein relate only to events as of the date on which the statements are made. We do not undertake any obligation to publicly update or review any forward-looking statement except as required by law, whether as a result of new information, future developments or otherwise.

        If one or more of these or other risks or uncertainties materialize, or if our underlying assumptions prove to be incorrect, our actual results may vary materially from what we may have expressed or implied by these forward-looking statements. We caution that you should not place undue reliance on any of our forward-looking statements. You should specifically consider the factors identified in this prospectus supplement and the accompanying prospectus that could cause actual results to differ before making an investment decision to purchase our securities. Furthermore, new risks and uncertainties arise from time to time, and it is impossible for us to predict those events or how they may affect us.

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RISK FACTORS

        In addition to the other information included or incorporated by reference in this prospectus supplement and the accompanying prospectus, including the matters addressed under "Forward-Looking Statements," you should carefully consider the following risks before investing in our common stock. You should also read the risk factors and other cautionary statements, including those described under the sections entitled "Risk Factors" in SHI's Annual Report on Form 10-K for the year ended December 31, 2014, which is incorporated by reference in this prospectus supplement and the accompanying prospectus.

        We are subject to certain risks and hazards due to the nature of the business activities we conduct. The risks discussed below and incorporated by reference in this prospectus supplement and the accompanying prospectus, any of which could materially and adversely affect our business, financial condition, liquidity, results of operations and prospects, are not the only risks we face. We may experience additional risks and uncertainties not currently known to us or, as a result of developments occurring in the future, conditions that we currently deem to be immaterial may also materially and adversely affect our business, financial condition, liquidity, results of operations and prospects.

Risks Related to the Proposed Acquisition

Failure to complete the Proposed Acquisition could negatively affect our share price, future business and financial results.

        Completion of the Proposed Acquisition is not assured and is subject to risks, including the risks that necessary regulatory approvals and clearances will not be obtained or that other closing conditions will not be satisfied. If the Proposed Acquisition is not completed, our ongoing business and financial results may be adversely affected and we will be subject to several risks, including:

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having to pay certain significant transaction costs relating to the Proposed Acquisition without receiving the benefits of the Proposed Acquisition;



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our share price may decline to the extent that the current market prices reflect an assumption by the market that the Proposed Acquisition will be completed;



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we may be subject to litigation related to any failure to complete the Proposed Acquisition; and



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if the Proposed Acquisition fails to close as a result of our failure to obtain antitrust approvals for, or resolve any objections of antitrust authorities to, the Proposed Acquisition, we will be required to pay Seller a termination fee of $212.5 million.

Delays in completing the Proposed Acquisition may substantially reduce the expected benefits of the Proposed Acquisition.

        Satisfying the conditions to, and completion of, the Proposed Acquisition may take longer than, and could cost more than, we expect. Any delay in completing or any additional conditions imposed (including those imposed by governmental entities in order to approve the Proposed Acquisition) in order to complete the Proposed Acquisition may materially adversely affect the synergies and other benefits that we expect to achieve from the Proposed Acquisition and the integration of our businesses. In addition, we and OneMain each have the right to terminate the Stock Purchase Agreement if the Proposed Acquisition is not completed by March 2, 2016, subject to extension by either party for three months if any required antitrust or state consumer finance or insurance regulatory approvals have not been obtained.

        We have agreed to take all action (including the divestiture, licensing or holding separate of assets) as may be necessary to resolve any antitrust objections to the Proposed Acquisition by governmental entities, except we will not be required to commit or agree to divest, license or hold separate assets of the Company and/or OneMain that account for more than $677 million in aggregate revenue of the Company and/or OneMain, as the case may be, for the twelve months ended December 31, 2014.

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Divestitures or licensing of assets can be time consuming and may delay or prevent completion of the Proposed Acquisition. Because potential buyers will likely be aware of the circumstances of the sale or license, these assets could be sold or licensed at prices or rates lower than their fair market value.

We will incur substantial transaction fees and costs in connection with the Proposed Acquisition.

        We expect to incur a significant amount of non-recurring expenses in connection with the Proposed Acquisition, including legal, accounting and other expenses. In general, these expenses are payable by us whether or not the Proposed Acquisition is completed. Additional unanticipated costs may be incurred following consummation of the Proposed Acquisition in the course of the integration of our businesses and the business of OneMain. We cannot be certain that the elimination of duplicative costs or the realization of other efficiencies related to the integration of the two businesses will offset the transaction and integration costs in the near term, or at all.

In connection with the Proposed Acquisition, we may incur indebtedness that could have important consequences for our business and any investment in our securities.

        We are obligated to complete the Proposed Acquisition whether or not we consummate any related financing transactions. If we do incur debt in connection with the Proposed Acquisition, the incurrence of such indebtedness could have important consequences for our business and any investment in our securities, including increased risks related to our indebtedness.

        In addition, OneMain currently has a significant amount of indebtedness. The indenture governing OneMain's unsecured debt contains a number of restrictive covenants that impose significant operating and financial restrictions on OneMain and may limit our ability to integrate OneMain's operations, including, but not limited to, restrictions on OneMain's and its restricted subsidiaries', ability to:

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incur or guarantee additional indebtedness or issue certain preferred stock;



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make dividend payments or distributions on or purchases of OneMain's equity interests;



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make other restricted payments or investments;



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create certain liens;



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make certain dispositions of assets;



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engage in certain transactions with affiliates;



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sell securities of our subsidiaries;



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in the case of such restricted subsidiaries, incur limitations on the ability to pay dividends or make other payments; and



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merge, consolidate or sell all or substantially all of OneMain's properties and assets.

We and OneMain will be subject to various uncertainties while the Proposed Acquisition is pending that could adversely affect our financial results or the anticipated benefits of the Proposed Acquisition.

        Uncertainty about the effect of the Proposed Acquisition on counterparties to contracts, employees and other parties may have an adverse effect on us or the anticipated benefits of the Proposed Acquisition. These uncertainties could cause contract counterparties and others who deal with us or OneMain to seek to change existing business relationships with us or OneMain, and may impair our and OneMain's ability to attract, retain and motivate key personnel until the Proposed Acquisition is completed and for a period of time thereafter. Employee retention and recruitment may be particularly challenging prior to completion of the Proposed Acquisition, as our employees and prospective employees, and the employees and prospective employees of OneMain, may experience uncertainty about their future roles with us following the Proposed Acquisition.

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        The pursuit of the Proposed Acquisition and the preparation for the integration of the two companies may place a significant burden on management and internal resources. Any significant diversion of management attention away from ongoing business and any difficulties encountered in the transition and integration process could affect our financial results prior to and/or following the completion of the Proposed Acquisition and could limit us from pursuing attractive business opportunities and making other changes to our business prior to completion of the Proposed Acquisition or termination of the Stock Purchase Agreement.

Our assets, liabilities or results of operations could be adversely affected by known or unknown or unexpected events, conditions or actions that might occur at OneMain prior to the closing of the Proposed Acquisition.

        The OneMain assets, liabilities, business, financial condition, cash flows, operating results and prospects to be acquired or assumed by us by reason of the Proposed Acquisition could be adversely affected before or after the Proposed Acquisition closing as a result of known or previously unknown events or conditions occurring or existing before the Proposed Acquisition closing. Adverse changes in OneMain's business or operations could occur or arise as a result of actions by OneMain, legal or regulatory developments including the emergence or unfavorable resolution of pre-acquisition loss contingencies, deteriorating general business, market, industry or economic conditions, and other factors both within and beyond the control of OneMain. A significant decline in the value of OneMain assets to be acquired by us or a significant increase in OneMain liabilities to be assumed by us could adversely affect our future business, financial condition, cash flows, operating results and prospects following the completion of the Proposed Acquisition.

If completed, the Proposed Acquisition may not achieve its intended results, and we may be unable to successfully integrate our and OneMain's operations.

        We entered into the Stock Purchase Agreement with the expectation that the Proposed Acquisition will result in various benefits, including, among other things, cost savings and operating efficiencies. Achieving the anticipated benefits of the Proposed Acquisition is subject to a number of uncertainties, including whether our business and the business of OneMain can be integrated in an efficient and effective manner.

        It is possible that the integration process could take longer than anticipated and could result in the loss of valuable employees, additional and unforeseen expenses, the disruption of our ongoing business, processes and systems, or inconsistencies in standards, controls, procedures, practices, policies and compensation arrangements, any of which could adversely affect our ability to achieve the anticipated benefits of the Proposed Acquisition. There may be increased risk due to integrating financial reporting and internal control systems. Difficulties in combining operations of the two companies could also result in the loss of contract counterparties or other persons with whom we or OneMain conduct business and potential disputes or litigation with contract counterparties or other persons with whom we or OneMain conduct business. Our results of operations following the Proposed Acquisition could also be adversely affected by any issues attributable to either company's operations that arise or are based on events or actions that occur prior to the closing of the Proposed Acquisition. The integration process is subject to a number of uncertainties, and no assurance can be given that the anticipated benefits, expense savings and synergies will be realized or, if realized, the timing of their realization. Failure to achieve these anticipated benefits could result in increased costs or decreases in the amount of expected revenues and could adversely affect our future business, financial condition, operating results and prospects.

        In addition, pursuant to the terms of the Stock Purchase Agreement, if consumer finance regulatory approvals are received in states representing ninety percent of all OneMain loans and all of the other conditions to the Proposed Acquisition closing have been satisfied, then, at Seller's option and subject to certain requirements and limitations, the parties will be obligated to effect the closing and we will be required to pay the full purchase price. If this occurs, certain arrangements will need to

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be put in place to permit the closing, which could result in a disruption of OneMain's operations and adversely affect our financial condition or results of operation.

        After the closing of the Proposed Acquisition, we will be reliant on Seller to provide certain operational services and support to OneMain, and a failure by Seller to perform such services could materially increase our costs or disrupt our business, which could adversely affect our financial condition and results of operations.

The unaudited pro forma financial information in this prospectus supplement is presented for illustrative purposes only and does not purport to be indicative of our financial condition or results of operations following the Proposed Acquisition.

        The unaudited pro forma financial information contained in this prospectus supplement is presented for illustrative purposes only, is based on various adjustments, assumptions and preliminary estimates and may not be an indication of our financial condition or results of operations following the consummation of the offering made pursuant to this prospectus supplement and the Proposed Acquisition for several reasons. Our actual financial condition and results of operations following the consummation of the offering made pursuant to this prospectus supplement and the Proposed Acquisition may not be consistent with, or evident from, these pro forma financial statements. In addition, the assumptions used in preparing the pro forma financial information may not prove to be accurate, and other factors may affect our financial condition or results of operations following the consummation of the offering made pursuant to this prospectus supplement and the Proposed Acquisition. Our potential for future business success and operating profitability must be considered in light of the risks, uncertainties, expenses and difficulties typically encountered by recently combined companies. See "Unaudited Pro Forma Combined Financial Information" for more information.

This offering is not conditioned upon the closing of, and we are not required to use the net proceeds therefrom to consummate, the Proposed Acquisition, and even if we determine to use some or all of the net proceeds to fund the Proposed Acquistion, we may be unable to consummate the Proposed Acquisition. Accordingly, we will have broad discretion over the use of proceeds from this offering.

        This offering is not conditioned upon the closing of, and we are not required to use the net proceeds therefrom to consummate, the Proposed Acquisition. Accordingly, the proceeds from this offering will not be designated for a specific use. Under these circumstances, our board of directors and management will have broad discretion to use the proceeds of this offering in our business, including for general corporate purposes. See "Use of Proceeds."

        Even if we determine to use some or all of the net proceeds to fund the Proposed Acquistion, we may be unable to consummate the Proposed Acquisition. The Proposed Acquisition is subject to a number of conditions that must be satisfied before we can complete the transaction. While we anticipate closing the Proposed Acquisition by the third quarter of 2015, we cannot guarantee when, or whether, the Proposed Acquisition will be completed. The completion of the Proposed Acquisition is subject to a number of customary conditions, including, among other things:

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The expiration or early termination of any applicable waiting period under the HSR Act, as amended;



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receipt of all consents, authorizations or approvals of all state regulatory authorities governing consumer lending and insurance in various states in which OneMain or any of its subsidiaries operate;



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the accuracy of the other party's representations and warranties contained in the Stock Purchase Agreement as of the closing date of the Proposed Acquisition; and



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compliance by the other party with its covenants and agreements contained in the Stock Purchase Agreement.

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USE OF PROCEEDS

        We estimate that our net proceeds from the sale of 18,939,394 shares of our common stock offered pursuant to this prospectus supplement will be approximately $             million, after deducting the estimated fees and expenses of this offering. We intend to use the net proceeds from this offering, together with cash on hand, proceeds from the sale of investment securities and existing conduit facilities, to finance the Proposed Acquisition and/or for general corporate purposes, which may include debt repurchases and repayments, capital expenditures and other possible acquisitions. See "Risk Factors—Risks Related to the Proposed Acquisition—This offering is not conditioned upon the closing of, and we are not required to use the net proceeds therefrom to consummate, the Proposed Acquisition, and even if we determine to use some or all of the net proceeds to fund the Proposed Acquistion, we may be unable to consummate the Proposed Acquisition. Accordingly, we will have broad discretion over the use of proceeds from this offering." We will not receive any proceeds from the sale of common stock in this offering by the Selling Stockholder. See "Summary—The Offering."

        An affiliate of Citigroup Global Markets Inc., an underwriter in this offering, is the seller under the Stock Purchase Agreement relating to the Proposed Acquisition. As described above, we may use all or a portion of the net proceeds from this offering to fund the Proposed Acquisition. As a result, more than 5% of the net proceeds may be directed to such affiliate of Citigroup Global Markets Inc. Because of the foregoing, a "conflict of interest" is deemed to exist within the meaning of FINRA Rule 5121. Consequently, this offering is being conducted in accordance with FINRA Rule 5121. See "Underwriting (Conflicts of Interest)."

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CAPITALIZATION

        The following table sets forth our capitalization, as of December 31, 2014:

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on an actual basis;



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on an as adjusted basis giving effect to (i) the offering made pursuant to this prospectus supplement (before underwriting and transaction costs), (ii) net increases in consumer securitization debt of $1.2 billion and $314 million resulting from the securitization transactions consummated on February 26, 2015 and April 7, 2015, respectively, as if they had occurred on December 31, 2014 and (iii) the sale of $363 million retained interest in notes related to a previous securitization; and



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on a pro forma combined basis to give effect to (i) the Proposed Acquisition, (ii) the offering made pursuant to this prospectus supplement (before underwriting and transaction costs), (iii) net increases in consumer securitization debt of $1.2 billion and $314 million resulting from the securitization transactions consummated on February 26, 2015 and April 7, 2015, respectively, as if they had occurred on December 31, 2014 and (iv) the sale of $363 million retained interest in notes related to a previous securitization.

        This table contains unaudited information and should be read in conjunction with "Summary—Summary Consolidated Historical and Pro Forma Financial Data" in this prospectus supplement, "Management's Discussion and Analysis of Financial Condition and Results of Operations" and consolidated financial statements and related notes in our Annual Report on Form 10-K for the year ended December 31, 2014, which is incorporated by reference herein.

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UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

        The following unaudited pro forma condensed combined financial information presents the combination of the historical consolidated and combined balance sheet and statement of income of Springleaf and OneMain adjusted to give effect to the Proposed Acquisition and the financing arrangements in connection with the Proposed Acquisition. The unaudited pro forma condensed combined statement of income for the year ended December 31, 2014 (i) combines the historical consolidated statement of income of Springleaf and the historical consolidated and combined statement of income of OneMain, giving effect to the Proposed Acquisition as if it had been consummated on January 1, 2014, and (ii) reflects the 2014 Springleaf real estate assets sale transactions and the financing arrangements as if they had been consummated on January 1, 2014. The unaudited pro forma condensed combined balance sheet combines the historical condensed consolidated balance sheet of Springleaf and the historical condensed consolidated balance sheet of OneMain as of December 31, 2014, giving effect to the Proposed Acquisition and the financing arrangements as if they had been consummated on December 31, 2014. The historical consolidated and combined financial information of OneMain has been adjusted to reflect certain reclassifications (included in the "reclassifications" column) in order to conform to Springleaf's financial statement presentation.

        The unaudited pro forma condensed combined financial information was prepared using the acquisition method of accounting with Springleaf considered the acquirer of OneMain. Under the acquisition method of accounting, OneMain's specific identifiable tangible and intangible assets acquired and liabilities assumed are generally reflected at their respective fair values with any excess of the purchase price over the fair value of OneMain's net assets allocated to goodwill.

        As of the date of this prospectus supplement, the Proposed Acquisition has not closed and Springleaf has not completed the detailed valuation analysis necessary to arrive at the required estimates of the fair value of OneMain's assets to be acquired and the liabilities to be assumed and the related allocations of purchase price, nor has it identified all adjustments necessary to conform OneMain's accounting policies to Springleaf's accounting policies. A final determination of the fair value of OneMain's assets and liabilities, including intangible assets with both indefinite or finite lives, will be based on the actual net tangible and intangible assets and liabilities of OneMain that exist as of the closing date of the Proposed Acquisition and, therefore, cannot be made prior to the completion of the transaction. As a result of the foregoing, the pro forma adjustments are preliminary and are subject to change as additional information becomes available and as additional analyses are performed. The preliminary pro forma adjustments have been made solely for the purpose of providing the unaudited pro forma condensed combined financial information presented herein. Springleaf estimated the fair value of OneMain's assets and liabilities based on discussions with OneMain's management, preliminary valuation studies, due diligence and information presented in OneMain's public filings. Until the Proposed Acquisition is completed, both companies are limited in their ability to share certain information. Upon completion of the Proposed Acquisition, final valuations will be performed. Any increases or decreases in the fair value of relevant balance sheet amounts upon completion of the final valuations will result in differences from this pro forma condensed combined balance sheet and/or statement of income. The final acquisition method of accounting will be different from that reflected in the pro forma information presented herein, and this difference may be material.

        Assumptions and estimates underlying the unaudited adjustments to the pro forma condensed combined financial information (the "pro forma adjustments") are described in the accompanying notes. The historical consolidated financial statements have been adjusted in the unaudited pro forma condensed combined financial information to give effect to pro forma events that are: (1) directly attributable to the Proposed Acquisition; (2) factually supportable; and (3) with respect to the pro forma statement of income, expected to have a continuing impact on the combined results of Springleaf and OneMain following the Proposed Acquisition. The unaudited pro forma condensed combined financial information has been presented for illustrative purposes only and is not necessarily indicative

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of the operating results and financial position that would have been achieved had the Proposed Acquisition occurred on the date indicated. Further, the unaudited pro forma condensed combined financial information does not purport to project the future operating results or financial position of the combined company following the Proposed Acquisition.

        The unaudited pro forma condensed combined financial information, although helpful in illustrating the financial characteristics of the combined company under one set of assumptions, does not reflect the benefits of expected cost savings (or associated costs to achieve such savings), opportunities to earn additional revenue, or other factors that may result as a consequence of the Proposed Acquisition and, accordingly, do not attempt to predict or suggest future results. Specifically, the unaudited pro forma condensed combined statement of income excludes projected operating efficiencies and synergies expected to be achieved as a result of the Proposed Acquisition. The unaudited pro forma condensed combined financial information also excludes the effects of costs associated with any restructuring or integration activities or asset dispositions resulting from the Proposed Acquisition, as they are currently not known, and to the extent they occur, are expected to be non-recurring and will not have been incurred at the closing date of the Proposed Acquisition. However, such costs could affect the combined company following the Proposed Acquisition in the period the costs are incurred or recorded. Further, the unaudited pro forma condensed combined financial information does not reflect the effect of any regulatory actions that may impact the results of the combined company following the Proposed Acquisition.

        In October 2013, certain executives of Springleaf received a grant of incentive units in the Initial Stockholder. These incentive units are subject to their continued employment with the Company and provide benefits (in the form of distributions) in the event the Initial Stockholder makes distributions to one or more of its members that exceed certain specified amounts. In connection with the sale of our common stock by the Initial Stockholder, certain of the specified thresholds may be satisfied. Springleaf recognizes these incentive units in accordance with ASC 710, Compensation—General, and will recognize compensation expense at the time any distributions are made to the executives. If the underwriters' option to purchase additional shares is not exercised, Springleaf is not expected to recognize any compensation expense in the second quarter of 2015 related to the incentive units. If the underwriters' option to purchase additional shares is exercised in full, Springleaf is expected to recognize non-cash compensation expense of approximately $14 million in the second quarter of 2015 related to the incentive units. The unaudited pro forma condensed combined statement of income does not include any adjustment for such compensation expense.

        The unaudited pro forma condensed combined statement of income for the year ended December 31, 2014 has been prepared to give effect to the 2014 real estate assets sale transactions (collectively, the "Asset Sales") reported in our Current Report on Form 8-K filed November 13, 2014 and adjusted for additional sales completed subsequent to that filing. There are no adjustments for the Asset Sales or the additional sales completed subsequent to such Current Report on Form 8-K in the unaudited pro forma condensed combined balance sheet since the Asset Sales were completed prior to, and is reflected in the balance sheet amounts as of, December 31, 2014.

        The unaudited pro forma condensed combined financial information has been developed from and should be read in conjunction with:

•

the historical audited consolidated financial statements of Springleaf as of and for the year ended December 31, 2014 included in Springleaf's Annual Report on Form 10-K and incorporated by reference in this document; and



•

the historical audited consolidated and combined financial statements of OneMain as of December 31, 2014 and 2013, and for each of the years in the three-year period ended December 31, 2014 included in Springleaf's Current Report on Form 8-K filed April 27, 2015, and incorporated by reference herein.

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UNAUDITED PRO FORMA CONDENSED COMBINED BALANCE SHEET
As of December 31, 2014

        The following unaudited pro forma condensed combined balance sheet as of December 31, 2014, combines the December 31, 2014 historical combined balance sheets of Springleaf and OneMain assuming the companies had been combined on December 31, 2014 using the acquisition method of accounting.