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)

December 15, 2025

HA SUSTAINABLE INFRASTRUCTURE CAPITAL, INC.

(Exact Name of Registrant as Specified in its Charter)

Delaware

001-35877

46-1347456

(State or Other Jurisdiction
of Incorporation)

(Commission

File Number)

(IRS Employer
Identification No.)

One Park Place, Suite 200

Annapolis, Maryland 21401

(Address of principal executive offices)

(Zip Code)

Registrant’s telephone number, including area code: (410) 571-9860

(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:

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

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

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

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

Securities registered pursuant to Section 12(b) of the Exchange Act:


Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, $0.01 par value per share	HASI	New York Stock Exchange

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 ☐

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. ☐

Item 8.01 Other Information.

On December 15, 2025, HA Sustainable Infrastructure Capital, Inc. (the “Company”) announced that the Company and Kohlberg Kravis Roberts & Co. L.P. (“KKR”) have agreed to make an additional capital commitment of $500 million each for a combined total of $1 billion of new investment capacity into CarbonCount Holdings 1 LLC, a co-investment vehicle established by the Company and KKR to provide long-term capital solutions for sustainable infrastructure projects across the United States. In addition to the increased capital commitments, the Company and KKR agreed to extend the investment period to the earlier of the end of 2027 or when all commitments have been utilized.

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SIGNATURES

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

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HA SUSTAINABLE INFRASTRUCTURE CAPITAL, INC.

Dated: December 15, 2025

/s/ Steven L. Chuslo

Steven L. Chuslo

Executive Vice President and Chief Legal Officer

HA Sustainable Infrastructure Capital, Inc. 8-K