Main Street to Participate in the 2017 Wells Fargo Investment Thought Leadership Forum

HOUSTON, Dec. 4, 2017

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's common stock trades on the New York Stock Exchange ("NYSE") under the symbol "MAIN." In addition, Main Street has outstanding 6.125% Notes due 2023, which trade on the NYSE under the symbol "MSCA."

Contacts:
Main Street Capital Corporation
Dwayne L. Hyzak, President & COO, dhyzak@mainstcapital.com
Brent D. Smith, CFO, bsmith@mainstcapital.com
713-350-6000

Dennard Lascar Investor Relations
Ken Dennard / ken@dennardlascar.com
Mark Roberson / mroberson@dennardlascar.com
713-529-6600