Main Street Capital Underwriters Exercise Over-Allotment Option

HOUSTON, Aug. 26 /PRNewswire-FirstCall/ -- Main Street Capital Corporation ("Main Street") announced today that the underwriters of its recent follow-on public offering have exercised their over-allotment option and have purchased 420,000 additional shares of common stock at the offering price of $15.00 per share. The underwriters of Main Street's offering elected to exercise the full amount of the over-allotment option prior to the expiration of the 30-day option period. The net proceeds from the exercise of the over-allotment option are approximately $6.0 million, after deducting the applicable underwriting discounts. Including the net proceeds from exercise of the over-allotment option, the total net proceeds from Main Street's offering amounted to approximately $45.8 million.

Main Street intends to use all of the net proceeds from this offering to make investments in accordance with its investment objective and strategies, pay operating expenses and other cash obligations and for general corporate purposes. Pending such uses, Main Street currently intends to invest the net proceeds of this offering in marketable securities and idle funds investments, which may include investments in secured intermediate term bank debt, rated debt securities and other income producing investments.

The underwriters of this offering were Morgan Keegan & Company, Inc., BB&T Capital Markets, a division of Scott & Stringfellow, LLC, Janney Montgomery Scott LLC, and Madison Williams and Company LLC. The shares were sold pursuant to an effective shelf registration statement on Form N-2 that has been filed with, and has been declared effective by, the U.S. Securities and Exchange Commission. This press release does not constitute an offer to sell or the solicitation of an offer to buy the shares referred to in this press release.

ABOUT MAIN STREET CAPITAL CORPORATION

Main Street (http://www.mainstcapital.com/) is a principal investment firm that primarily provides long-term debt and equity capital to lower middle market companies. Main Street's investments are made to support management buyouts, recapitalizations, growth financings and acquisitions of companies that operate in diverse industry sectors and generally have annual revenues ranging from $10 million to $100 million. Main Street seeks to partner with entrepreneurs, business owners and management teams and generally provides "one-stop" financing alternatives to its portfolio companies.

Forward-Looking Statements

This press release may contain certain forward-looking statements. Any such statements other than statements of historical fact are likely to be affected by other unknowable future events and conditions, including elements of the future that are or are not under Main Street's control, and that Main Street may or may not have considered; accordingly, such statements cannot be guarantees or assurances of any aspect of future performance. Actual performance and results could vary materially from these estimates and projections of the future. Such statements speak only as of the time when made, and Main Street undertakes no obligation to update any such statement now or in the future.

Contacts: Main Street Capital Corporation ------------------------------- Todd A. Reppert, President and CFO [e-mail] 713-350-6000 Dennard Rupp Gray and Easterly, LLC ----------------------------------- Ken Dennard | [e-mail] Ben Burnham | [e-mail] 713-529-6600

Main Street Capital Corporation

CONTACT: Todd A. Reppert, President and CFO of Main Street Capital
Corporation, [phone], [e-mail]; or Ken Dennard,
[e-mail], or Ben Burnham, [e-mail], both of Dennard Rupp
Gray and Easterly, LLC, [phone], for Main Street Capital Corporation

Web Site: http://www.mainstcapital.com/