UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 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 9, 2015

NEXPOINT CAPITAL, INC.

(Exact name of Registrant as Specified in Its Charter)

300 Crescent Court, Suite 700

Dallas, Texas 75201

(Address of Principal Executive Offices)(Zip Code)

Registrant’s telephone number, including area code: (972) 628-4100

(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:

On January 6, 2015, NexPoint Capital, Inc. (the “Company”) entered into a senior, secured revolving credit facility (the “Credit Facility”) with State Street Bank and Trust Company (“State Street”), as lender and agent. Under the Credit Facility, State Street has agreed to extend credit to the Company in an aggregate principal amount of up to $25 million, subject to borrowing base availability and restrictions on the Company’s total outstanding debt.

Loans under the Credit Facility will bear interest (at the Company’s election) at either (1) the higher of (i) the federal funds rate plus 1.25% per annum and (ii) the daily one-month London Interbank Offered Rate (“LIBOR”) plus 1.25% per annum or (2) one-, two- or three-month LIBOR plus 1.15% per annum. Interest is payable monthly in arrears. The Company will pay an unused commitment fee of 0.15% per annum on committed but unused amounts under the Credit Facility. All outstanding borrowings under the Credit Facility will mature and the principal, together with all accrued and unpaid interest, will be due and payable on January 5, 2016.

In connection with the Credit Facility, the Company has also entered into a security agreement with State Street, both in its capacity as agent for the lenders under the Credit Facility and in its capacity as custodian to the Company, pursuant to which the Company grants State Street a security interest in all of the Company’s assets. State Street serves as the Company’s custodian and sub-administrator pursuant to separate agreements.

The Credit Facility contains certain customary covenants including that senior securities representing indebtedness will not exceed 33 1/3% of the Company’s net assets. The Credit Facility also includes customary representations and warranties, conditions precedent to borrowings and events of default.

In accordance with the Company’s share pricing policy as disclosed in the Company’s prospectus, on January 5, 2014, the Company’s board of directors established a new public offering price per share following a decline in the Company’s net asset value per share.

The Company changed the public offering price of its common stock to $10.00 per share. The decrease in the public offering price will be effective for the Company’s closing on January 15, 2015.

The information set forth under Item 1.01 of this current report on Form 8-K is hereby incorporated in this Item 2.03 by reference.

Forward-Looking Statements

This Current Report on Form 8-K may contain certain forward-looking statements, including statements with regard to the future performance and operation of the Company. Words such as “believes,” “expects,” “projects” and “future” or similar expressions are intended to identify forward-looking statements. These forward-looking statements are subject to the inherent uncertainties in predicting future results and conditions. Certain factors could cause actual results to differ materially from those projected in these forward-looking statements, and some of these factors are enumerated in the filings the Company makes with the Securities and Exchange Commission. The Company undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

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SIGNATURES

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