Main Street Announces New Portfolio Investment

Invests $32.9 Million in Colonial Electric Company, LLC

Houston, TX /PRNewswire/ - Main Street Capital Corporation (NYSE: MAIN) ("Main Street") is pleased to announce that it recently completed a new portfolio investment to facilitate the recapitalization of Colonial Electric Company, LLC ("Colonial" or the "Company"), a leading provider of electrical contracting services in the mid-Atlantic region of the United States. Main Street, along with its co-investor, partnered with the Company's existing owners and senior management team to facilitate the transaction, with Main Street funding $32.9 million in a combination of first-lien, senior secured term debt and a direct equity investment. Main Street and its co-investor are also providing Colonial with a revolving line of credit to support the Company's working capital needs.

Founded in 1970 and headquartered in Harwood, Maryland, Colonial is a third generation, family-owned electrical contracting services provider, focused on multi-family housing in Maryland, Northern Virginia and Washington, D.C.

About Main Street Capital Corporation
Main Street (www.mainstcapital.com) is a principal investment firm that primarily provides long-term debt and equity capital to lower middle market companies and debt capital to middle market companies. Main Street's portfolio investments are typically made to support management buyouts, recapitalizations, growth financings, refinancings and acquisitions of companies that operate in diverse industry sectors. Main Street seeks to partner with entrepreneurs, business owners and management teams and generally provides "one stop" financing alternatives within its lower middle market portfolio. Main Street's lower middle market companies generally have annual revenues between $10 million and $150 million. Main Street's middle market debt investments are made in businesses that are generally larger in size than its lower middle market portfolio companies.

Main Street, through its wholly owned portfolio company MSC Adviser I, LLC ("MSC Adviser"), also maintains an asset management business through which it manages investments for external parties. MSC Adviser is registered as an investment adviser under the Investment Advisers Act of 1940.