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

Main Street Capital Corporation

(Exact name of registrant as specified in its charter)

Not Applicable

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:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

On October 30, 2020, after successfully receiving the required approval of the stockholders of HMS Income Fund, Inc. (“HMS Income”), Main Street Capital Corporation (the “Company”), MSC Adviser I, LLC, the Company’s wholly owned subsidiary (the “External Investment Manager”), and HMS Adviser LP (“HMS Adviser”) consummated the transactions contemplated by that certain asset purchase agreement by and among the External Investment Manager, HMS Adviser and the other parties thereto (the “Closing”) whereby the External Investment Manager became the sole investment adviser and administrator to HMS Income pursuant to an Investment Advisory and Administrative Services Agreement entered into between the External Investment Manager and HMS Income (the “Advisory Agreement”). The Advisory Agreement includes a 1.75% management fee (reduced from 2.00%) and the same 20% incentive fee calculations as under the prior advisory agreement between HMS Income and HMS Adviser. After the Closing, HMS Income changed its name to MSC Income Fund, Inc.

The above summary of the Advisory Agreement is not complete and is qualified in its entirety by the full text of the Advisory Agreement, a copy of which is filed with this Current Report on Form 8-K as Exhibit 10.1 and incorporated herein by reference.

On October 28, 2020, the Company issued a press release. A copy of such press release is filed with this Current Report on Form 8-K as Exhibit 99.1 and is incorporated herein by reference.

(d)  Exhibits

SIGNATURES

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