Exhibit 99.1

FS Investment Corporation Reports Fourth Quarter and 2014 Annual Financial Results

PHILADELPHIA, PA, March 2, 2015 – FS Investment Corporation (NYSE: FSIC), a publicly traded business development company focused on providing customized credit solutions to private middle market U.S. companies, announced its operating results for the quarter and year ended December 31, 2014.

Financial Highlights for the Quarter Ended December 31, 2014¹

Financial Highlights for the Year Ended December 31, 2014¹

Michael C. Forman, Chairman and Chief Executive Officer of FSIC said, “I am pleased to report that in 2014 FSIC generated a total return, based on net asset value, of 7.17%. Throughout the year, we continued to grow our portfolio allocation to our core investment strategies, which include direct originations and opportunistic investments, and we maintained our focus on investing in senior secured debt.”

Forman added, “We at Franklin Square believe we are well-positioned to continue to generate reliable and sustainable income for our shareholders. We believe the scale of our platform enables us to participate in a less competitive part of the direct originations market and enables us to be opportunistic in our investment selection to maximize our risk-adjusted returns. We also believe the sourcing and credit expertise of GSO / Blackstone, our sub-advisor, provide us with a significant breadth of investment opportunities and to date has resulted in strong credit performance in our portfolio.”

Operating Results

Portfolio Highlights

Total Portfolio Activity

Direct Origination Activity

Balance Sheet Summary

Reconciliation of Non-GAAP Financial Measures¹

Conference Call Information

FSIC will hold its conference call to discuss its financial results for the quarter and year ended December 31, 2014 on Tuesday, March 3, 2015, at 9:00 a.m. Eastern Time. Interested parties are invited to participate via telephone or webcast, which will be hosted on a webcast link located on the “Investor Relations” section of its website at www.fsinvestmentcorp.com. For participants joining via telephone, please dial 1 (800) 446-1671 at least 10 minutes prior to the beginning of the conference call and provide the confirmation code 38809545 when prompted. An audio archive of the call will be available for replay. The link to the audio archive can be found under the “Investor Relations” section of FSIC’s website and will be available for a period of 30 days following the call.

Supplemental Information

FSIC will provide a financial information presentation with additional details on its financial results for the quarter and year ended December 31, 2014 in advance of the March 3, 2015 conference call. This presentation will be made available under the “Presentations and Reports” page within the “Investor Relations” section of FSIC’s website (www.fsinvestmentcorp.com). For inquiries, please contact Jim Ballan at (267) 439-4375.

About FS Investment Corporation

FS Investment Corporation (NYSE: FSIC) is a publicly traded business development company (“BDC”) focused on providing customized credit solutions to private middle market U.S. companies. FSIC seeks to invest primarily in the senior secured debt and, to a lesser extent, the subordinated debt of private middle market companies to achieve the best risk-adjusted returns for its investors. In connection with its debt investments, FSIC may receive equity interests such as warrants or options.

FSIC is advised by FB Income Advisor, LLC, an affiliate of Franklin Square Capital Partners (“Franklin Square”), and is sub-advised by GSO / Blackstone Debt Funds Management LLC, an affiliate of GSO Capital Partners (“GSO”). GSO, with approximately $72.9 billion in assets under management as of December 31, 2014, is the credit platform of Blackstone, one of the world’s leading managers of alternative investments. For more information, please visit www.fsinvestmentcorp.com.

About Franklin Square

Franklin Square is a leading manager of alternative investment funds designed to enhance investors’ portfolios by providing access to asset classes, strategies and asset managers that typically have been available to only the largest institutional investors. The firm’s funds offer “endowment-style” investment strategies that help construct diversified portfolios and manage risk. Franklin Square strives not only to maximize investment returns but also to set the industry standard for best practices by focusing on transparency, investor protection and education for investment professionals and their clients.

Founded in Philadelphia in 2007, Franklin Square quickly established itself as a leader in the world of alternative investments by introducing innovative credit-based income funds, including the industry’s first non-traded BDC. The firm managed approximately $13.6 billion in assets as of September 30, 2014. For more information, please visit www.franklinsquare.com.

Other Information

The information in this press release is summary information only and should be read in conjunction with FSIC’s annual report on Form 10-K for the year ended December 31, 2014, which FSIC filed with the U.S. Securities and Exchange Commission (the “SEC”) on March 2, 2015, as well as FSIC’s other reports filed with the SEC. A copy of FSIC’s annual report on Form 10-K for the year ended December 31, 2014 and FSIC’s other reports filed with the SEC can be found on FSIC’s website at www.fsinvestmentcorp.com and the SEC’s website at www.sec.gov.

Certain Information About Distributions

The determination of the tax attributes of FSIC’s distributions is made annually as of the end of its fiscal year based upon its taxable income and distributions paid, in each case, for the full year. Therefore, a determination as to the tax attributes of the distributions made on a quarterly basis may not be representative of the actual tax attributes for a full year. FSIC intends to update stockholders quarterly with an estimated percentage of its distributions that resulted from taxable ordinary income. The actual tax characteristics of distributions to stockholders will be reported to stockholders annually on Form 1099-DIV.

The timing and amount of any future distributions on FSIC’s shares of common stock are subject to applicable legal restrictions and the sole discretion of its board of directors. There can be no assurance as to the amount or timing of any such future distributions.

FSIC may fund its cash distributions to stockholders from any sources of funds legally available to it, including proceeds from the sale of shares of FSIC’s common stock, borrowings, net investment income from operations, capital gains proceeds from the sale of assets, non-capital gains proceeds from the sale of assets and dividends or other distributions paid to it on account of preferred and common equity investments in portfolio companies. FSIC has not established limits on the amount of funds it may use from available sources to make distributions. There can be no assurance that FSIC will be able to pay distributions at a specific rate or at all.

Forward-Looking Statements and Important Disclosure Notice

This announcement may contain certain forward-looking statements, including statements with regard to future events or the future performance or operations of FSIC. Words such as “believes,” “expects,” “projects,” and “future” or similar expressions are intended to identify forward-looking statements. These forward-looking statements are subject to the inherent uncertainties in predicting future results and conditions. Certain factors could cause actual results to differ materially from those projected in these forward-looking statements. Factors that could cause actual results to differ materially include changes in the economy, risks associated with possible disruption in FSIC’s operations or the economy generally due to terrorism or natural disasters, future changes in laws or regulations and conditions in FSIC’s operating area, and the price at which shares of FSIC’s common stock trade on the New York Stock Exchange. Some of these factors are enumerated in the filings FSIC makes with the SEC. FSIC undertakes no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

The press release above contains summaries of certain financial and statistical information about FSIC. The information contained in this press release is summary information that is intended to be considered in the context of FSIC’s SEC filings and other public announcements that FSIC may make, by press release or otherwise, from time to time. FSIC undertakes no duty or obligation to update or revise the information contained in this press release. In addition, information related to past performance, while helpful as an evaluative tool, is not necessarily indicative of future results, the achievement of which cannot be assured. Investors should not view the past performance of FSIC, or information about the market, as indicative of FSIC’s future results.

Individual investors and endowments may have different investment horizons, liquidity needs and risk tolerances. In addition, fees that may be incurred by an investor in a fund sponsored by Franklin Square may be different than fees incurred by an endowment investing in similar assets as those in which the funds invest.

Non-GAAP Financial Measures

This press release contains certain financial measures that have not been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”). FSIC uses these non-GAAP financial measures internally in analyzing financial results and believes that the use of these non-GAAP financial measures is useful to investors as an additional tool to evaluate ongoing results and trends and in comparing FSIC’s financial results with other BDCs.

Non-GAAP financial measures are not meant to be considered in isolation or as a substitute for comparable GAAP financial measures, and should be read only in conjunction with FSIC’s consolidated financial statements prepared in accordance with GAAP. A reconciliation of non-GAAP financial measures to the most directly comparable GAAP measures has been provided in this press release, and investors are encouraged to review the reconciliation.