Form 8-K

8-K — BLACK HILLS CORP /SD/

Accession: 0001193125-26-429192

Filed: 2026-10-23

Period: 2026-10-22

CIK: 0001130464

SIC: 4911 (ELECTRIC SERVICES)

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — bkh-20261022.htm (Primary)

EX-99.1 (bkh-ex99_1.htm)

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8-K

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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): October 22, 2026

Black Hills Corporation

(Exact name of Registrant as Specified in Its Charter)

________

South Dakota

001-31303

46-0458824

(State or Other Jurisdiction

of Incorporation)

(Commission File Number)

(IRS Employer

Identification No.)

7001 Mount Rushmore Road

Rapid City, South Dakota

57702

(Address of Principal Executive Offices)

(Zip Code)

Registrant's Telephone Number, Including Area Code: 605 721-1700

Name

(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

Common stock of $1.00 par value

BKH

The 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 ☐

Item 7.01 Regulation FD Disclosure.

On October 22, 2026, Black Hills Corporation issued a press release announcing the anticipated name and ticker symbol of the combined company in the event NorthWestern Energy Group, Inc. and Black Hills Corporation receive satisfactory, final regulatory approval from the Montana Public Service Commission and complete their proposed merger. A copy of the press release is furnished as Exhibit 99.1 to this Form 8-K.

Item 9.01 Financial Statements and Exhibits.

Exhibit No.

Description

99.1

Press Release dated October 22, 2026 (furnished herewith)

104

Cover Page Interactive Data File (formatted as 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.

BLACK HILLS CORPORATION

Date:

October 22, 2026

By:

/s/ Kimberly F. Nooney

Kimberly F. Nooney

Senior Vice President and Chief Financial Officer

EX-99.1

Filename: bkh-ex99_1.htm · Sequence: 2

EX-99.1

Subject to Receipt of Satisfactory Final Regulatory Approval and Completion of Proposed Merger, Black Hills Corp. to be Renamed Bright Horizon Energy Corporation with Ticker Symbol “HZN”

•

The Montana Public Service Commission is expected to consider the merger prior to November 12, 2026, and completion remains subject to satisfactory final regulatory approval by the Commission.

•

Trading under new company name and ticker symbol is only expected upon completion of the merger.

RAPID CITY, SD and BUTTE, MT / SIOUX FALLS, SD — Oct. 22, 2026 — Black Hills Corp. (NYSE: BKH) and NorthWestern Energy Group, Inc. d/b/a NorthWestern Energy (Nasdaq: NWE) today announced plans for the name and ticker symbol of the combined company in the event their proposed merger receives final, satisfactory regulatory approval and is completed. If the proposed merger is approved and completed, Black Hills Corp. will be renamed Bright Horizon Energy Corporation (“Bright Horizon Energy”), its common stock will trade on the New York Stock Exchange (NYSE) under the ticker symbol “HZN,” and NorthWestern Energy will become a wholly owned subsidiary of Bright Horizon Energy.

There is no action required by shareholders in connection with the name and ticker symbol change. Shares of Black Hills Corp. will continue trading under the symbol “BKH” on the NYSE and shares of NorthWestern Energy will continue trading under the symbol “NWE” on the Nasdaq while the merger is pending.

The merger has previously received approvals from shareholders of both companies, the regulatory commissions of Nebraska and South Dakota, the Federal Energy Regulatory Commission, and clearance under the Hart-Scott-Rodino Act.

###

About Black Hills Corp.

Black Hills Corp. (NYSE: BKH) is a customer-focused, growth-oriented utility company with a tradition of improving life with energy and a vision to be the energy partner of choice. Based in Rapid City, South Dakota, the company serves 1.37 million natural gas and electric utility customers in eight states: Arkansas, Colorado, Iowa, Kansas, Montana, Nebraska, South Dakota and Wyoming. More information is available at www.blackhillscorp.com.

About NorthWestern Energy

NorthWestern Energy Group, Inc., doing business as NorthWestern Energy, provides essential energy infrastructure and valuable services that enrich lives and empower communities while serving as long-term partners to our customers and communities. We work to deliver safe,

reliable, and innovative energy solutions that create value for customers, communities, employees, and investors. We do this by providing low-cost and reliable service performed by highly adaptable and skilled employees. We provide electricity and / or natural gas to approximately 850,300 customers in Montana, South Dakota, Nebraska, and Yellowstone National Park. Our operations in Montana and Yellowstone National Park are conducted through our subsidiary, NW Corp, and our operations in South Dakota and Nebraska are conducted through our subsidiary, NWE Public Service. We have provided service in South Dakota and Nebraska since 1923 and in Montana since 2002.

Forward Looking Statements

Information in this communication, other than statements of historical facts, may constitute forward-looking statements, within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These statements include, but are not limited to, statements about the planned name and ticker symbol of the combined company, its exchange listing, expectations regarding regulatory approvals and the timing thereof and other statements that are not historical facts. Forward-looking statements may be identified by terminology such as “may,” “will,” “should,” “targets,” “scheduled,” “plans,” “intends,” “goal,” “anticipates,” “expects,” “believes,” “forecasts,” “outlook,” “estimates,” “potential,” or “continue” or negatives of such terms or other comparable terminology. The forward-looking statements are based on Black Hills and NorthWestern Energy’s current expectations, plans and estimates. Black Hills and NorthWestern Energy believe these assumptions to be reasonable, but there is no assurance that they will prove to be accurate. All forward-looking statements are subject to risks, uncertainties and other factors that may cause the actual results, performance or achievements of Black Hills or NorthWestern Energy to differ materially from any results expressed or implied by such forward-looking statements. Such factors include, among others, (1) the risk of delays in consummating the potential transaction, including as a result of required regulatory approvals, which may not be obtained on the expected timeline, or at all, (2) the risk of any event, change or other circumstance that could give rise to the termination of the merger agreement, (3) the risk that required regulatory approvals are subject to conditions not anticipated by Black Hills and NorthWestern Energy, (4) the possibility that any of the anticipated benefits and projected synergies of the potential transaction will not be realized or will not be realized within the expected time period, (5) disruption to the parties’ businesses as a result of the announcement and pendency of the transaction, including potential distraction of management from current plans and operations of Black Hills or NorthWestern Energy and the ability of Black Hills or NorthWestern Energy to retain and hire key personnel, (6) reputational risk and the reaction of each company’s customers, suppliers, employees or other business partners to the transaction, (7) the possibility that the transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events, (8) the outcome of any legal or regulatory proceedings that may be instituted against Black Hills or NorthWestern Energy related to the merger agreement or the transaction, (9) the risks associated with third party contracts containing consent and/or other provisions that may be triggered by the proposed transaction, (10) legislative, regulatory, political, market, economic and other conditions, developments and uncertainties affecting Black Hills’ or NorthWestern Energy’s businesses; (11) the evolving legal, regulatory and tax regimes under which Black Hills and NorthWestern Energy operate; (12) restrictions during the pendency of the proposed transaction that may impact Black Hills’ or NorthWestern Energy’s ability to pursue certain business opportunities or strategic transactions; and (13) unpredictability and severity of catastrophic events, including, but not limited to, extreme weather, natural disasters, acts of terrorism or outbreak of war or hostilities, as well as Black Hills’ and NorthWestern Energy’s response to any of the aforementioned factors.

Additional factors which could affect future results of Black Hills and NorthWestern Energy can be found in Black Hills’ Registration Statement on Form S-4 as well as its Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, and NorthWestern Energy’s Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, in each case filed with the SEC and available on the SEC’s website at

http://www.sec.gov. Black Hills and NorthWestern Energy disclaim any obligation and do not intend to update or revise any forward-looking statements contained in this communication, which speak only as of the date hereof, whether as a result of new information, future events or otherwise, except as required by federal securities laws.

No Offer or Solicitation

This document is for informational purposes only and is not intended to and shall not constitute an offer to buy or sell or the solicitation of an offer to buy or sell any securities, or a solicitation of any vote or approval, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offering of securities shall be made, except by means of a prospectus meeting the requirements of Section 10 of the U.S. Securities Act of 1933, as amended.

Black Hills Corp. Contacts

NorthWestern Energy Contacts

Investors

Sal Diaz

Travis Meyer

investorrelations@blackhillscorp.com

travis.meyer@northwestern.com

Media

24-Hour Media Relations Line

Jo Dee Black

888-242-3969

866-622-8081

jodee.black@northwestern.com

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