UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of report (Date of earliest event reported): January 17, 2018

BAIN CAPITAL SPECIALTY FINANCE, INC.

(Exact name of Registrant as Specified in Its Charter)

Registrant’s telephone number, including area code: (617) 516-2000

(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 (see General Instruction A.2. below):

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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 o

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. o

Item 3.02. Unregistered Sales of Equity Securities.

On January 17, 2018, Bain Capital Specialty Finance, Inc. (the “Company”) delivered a capital drawdown notice to its investors due on January 31, 2018 relating to the sale of 6,163,523.61 shares of the Company’s common stock, par value $0.001 per share (the “Common Stock”) for an aggregate offering price of $125,427,705.50. The sale is expected to close on or around January 31, 2018. With this sale, approximately half of the Company’s total commitments will be drawn.

The sale of Common Stock is being made pursuant to subscription agreements entered into by the Company and its investors. Under the terms of the subscription agreements, investors are required to fund drawdowns to purchase shares of Common Stock up to the amount of their respective capital commitments on an as-needed basis with a minimum of 10 business days’ prior notice.

The sale of the common stock is exempt from the registration requirements of the Securities Act of 1933, as amended, pursuant to Section 4(a)(2) thereof. The Company has not engaged in general solicitation or advertising with regard to the issuance and sale of the Common Stock and has not offered securities to the public in connection with such issuance and sale.

2

SIGNATURES

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

3