UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): January 13, 2015

FS Investment Corporation

(Exact name of Registrant as specified in its charter)

Registrant’s telephone number, including area code: (215) 495-1150

None

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

As previously announced, the board of directors (the “Board”) of FS Investment Corporation (the “Company”) approved the declaration and payment of regular cash distributions to the Company’s stockholders on a quarterly rather than monthly basis, effective January 1, 2015.

On January 13, 2015, the Board of the Company declared a regular quarterly cash distribution of $0.22275 per share. The regular quarterly cash distribution will be paid on or about April 2, 2015 to stockholders of record as of the close of business on March 25, 2015.

For future quarters, the Company currently intends to announce regular quarterly cash distributions when it releases its overview of operating results for the previously completed fiscal quarter. Accordingly, the Company currently anticipates that it will announce the regular quarterly cash distribution for the second quarter ended June 30, 2015 when it releases its overview of operating results for the fiscal quarter ended March 31, 2015.

Additionally, on January 13, 2015, the Company announced that it will host a 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. A copy of the press release announcing the conference call is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Certain Information About Distributions

The determination of the tax attributes of the Company’s distributions is made annually as of the end of the Company’s 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. The Company 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 to stockholders are subject to applicable legal restrictions and the sole discretion of the Board. There can be no assurance as to the amount or timing of any such future distributions.

Forward-Looking Statements

This Current Report on Form 8-K may contain certain forward-looking statements, including statements with regard to the future performance and operation of the Company. 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 the Company’s operations or the economy generally due to terrorism or natural disasters, future changes in laws or regulations and conditions in the Company’s operating area. Some of these factors are enumerated in the filings the Company makes with the Securities and Exchange Commission. The Company undertakes no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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