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) June 23, 2025

Northern States Power Company

(Exact name of registrant as specified in its charter)

Wisconsin

001-03140

39-0508315

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(IRS Employer

Identification No.)


1414 West Hamilton Avenue
Eau Claire, WI		54701
(Address of principal executive offices)		(Zip Code)

Registrant’s telephone number, including area code: (715) 852-5812

N/A

(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 Act:

Title of each class

Trading

Symbol(s)

Name of each exchange

on which registered

N/A

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 Events.

On June 23, 2025, Northern States Power Company, a Wisconsin corporation (“NSP-Wisconsin”), issued $250 million in aggregate principal amount of 5.65% First Mortgage Bonds, Series due June 15, 2054 (the “bonds”) pursuant to an Underwriting Agreement among NSP-Wisconsin and BNP Paribas Securities Corp., CIBC World Markets Corp. and RBC Capital Markets, LLC, as representatives of the underwriters named therein in a reopening of the existing series of previously issued and outstanding 5.65% First Mortgage Bonds, Series due June 15, 2054. The bonds were issued pursuant to the registration statement on Form S-3 (File No. 333-278797-03) (the “Registration Statement”). A prospectus supplement relating to the offering and sale of the bonds was filed with the Securities and Exchange Commission on June 18, 2025. The bonds are governed by NSP-Wisconsin’s Supplemental and Restated Trust Indenture, dated March 1, 1991, as supplemented, by and between NSP-Wisconsin and U.S. Bank Trust Company, National Association, as successor trustee, and the Supplemental Trust Indenture dated as of May 13, 2024.

This Current Report on Form 8-K is being filed to report as exhibits certain documents in connection with that offering and sale for incorporation by reference into the Registration Statement.

Item 9.01.

Financial Statements and Exhibits.

(d)

Exhibits.


Exhibit		Description

4.01		Supplemental Indenture dated as of May 13, 2024 between Northern States Power Company and U.S. Bank Trust Company, National Association, as successor Trustee, creating 5.65% First Mortgage Bonds, Series due June 15, 2054 (incorporated by reference to Exhibit 4.01 to the Current Report on Form 8-K filed by NSP-Wisconsin on May 16, 2024 (file no. 001-03140)).

5.01		Opinion of Tara R. Duginske regarding the validity of certain securities.

5.02		Opinion of Foley & Lardner LLP regarding the validity of certain securities.

104		Cover Page Interactive Data File (embedded within the Inline XBRL document)

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.


NORTHERN STATES POWER COMPANY
(a Wisconsin corporation)

By:		/s/ Todd A. Wehner
Name:		Todd A. Wehner
Title:		Vice President, Treasurer

Date: June 23, 2025

NORTHERN STATES POWER CO /WI/ 8-K