Exhibit 99.1

	NEWS RELEASE
	Contacts: MSC Income Fund, Inc. Dwayne L. Hyzak, CEO, dhyzak@mainstcapital.com Cory E. Gilbert, CFO, cgilbert@mainstcapital.com 713-350-6000 Dennard Lascar Investor Relations Ken Dennard / ken@dennardlascar.com Zach Vaughan / zvaughan@dennardlascar.com 713-529-6600

MSC Income Fund Announces Third Quarter 2025 Private Loan Portfolio

Activity

HOUSTON – October 9, 2025 – MSC Income Fund, Inc. (NYSE: MSIF) (“MSC Income” or the

“Fund”) is pleased to announce the following recent activity in its private loan portfolio. During the

third quarter of 2025, MSC Income originated new or increased commitments in its private loan

portfolio of $94.2 million and funded total investments across its private loan portfolio with a cost

basis totaling $74.6 million.

The following represent notable new private loan commitments and investments during the third

quarter of 2025:

•$22.4 million in a first lien senior secured term loan, $3.2 million in a first lien senior secured

revolver, $3.2 million in a first lien senior secured delayed draw term loan and $1.2 million in

equity to a provider of HVAC and plumbing installation services to multifamily and

commercial end markets;

•$10.0 million in a first lien senior secured term loan, $5.0 million in a first lien senior secured

revolver, $10.0 million in a first lien senior secured delayed draw term loan and $1.0 million in

equity to a provider of new and refurbished pad mounted transformers to datacenter,

commercial and industrial end markets;

•$13.8 million in a first lien senior secured term loan, $3.5 million in a first lien senior secured

revolver, $3.9 million in a first lien senior secured delayed draw term loan and $1.0 million in

equity to a provider of custom glass fabrication, installation and specialty coating solutions;

•Increased commitment of $6.5 million in an incremental first lien senior secured term loan to a

manufacturer of chemicals and lubricant additives serving large specialty chemical companies;

and

•Increased commitment of $4.2 million in an incremental first lien senior secured term loan and

$0.9 million in an incremental first lien senior secured revolver to a provider of highly

technical specialty services to datacenters and various other diverse end markets.

As of September 30, 2025, MSC Income’s private loan portfolio included total investments at cost of

approximately $761.1 million across 81 unique companies. The private loan portfolio, as a percentage

of cost, included 92.0% invested in first lien senior secured debt investments and 8.0% invested in

equity investments or other securities.

ABOUT MSC INCOME FUND, INC.

The Fund (www.mscincomefund.com) is a principal investment firm that primarily provides debt

capital to private companies owned by or in the process of being acquired by a private equity fund.

The Fund’s portfolio investments are typically made to support leveraged buyouts, recapitalizations,

growth financings, refinancings and acquisitions of companies that operate in diverse industry sectors.

The Fund seeks to partner with private equity fund sponsors and primarily invests in secured debt

investments within its private loan investment strategy. The Fund also maintains a portfolio of

customized long-term debt and equity investments in lower middle market companies, and through

those investments, the Fund has partnered with entrepreneurs, business owners and management teams

in co-investments with Main Street Capital Corporation (NYSE: MAIN) (“Main Street”) utilizing the

customized “one-stop” debt and equity financing solutions provided in Main Street’s lower middle

market investment strategy. The Fund’s private loan portfolio companies generally have annual

revenues between $25 million and $500 million. The Fund’s lower middle market portfolio companies

generally have annual revenues between $10 million and $150 million.

ABOUT MSC ADVISER I, LLC

MSC Adviser I, LLC (“MSCA”) is a wholly-owned subsidiary of Main Street that is registered as an

investment adviser under the Investment Advisers Act of 1940, as amended. MSCA serves as the

investment adviser and administrator of the Fund in addition to several other advisory clients.