BLACK HILLS CORP /SD/

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No.)

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☒Definitive Proxy Statement

☐ Definitive Additional Materials

☐ Soliciting Materials under §240.14a-12

Notice of 2026

Annual Meeting of Shareholders

and Proxy Statement

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

We are pleased to invite you to virtually attend the annual meeting of shareholders of Black Hills Corporation.

The meeting is to be held as a virtual-only webcast on Wednesday, April 29, 2026 at 10:30 a.m. (Mountain Time). You may attend the annual meeting and vote your shares electronically during the meeting via the internet at www.virtualshareholdermeeting.com/BKH2026. To enter the annual meeting, you must enter the 16-digit control number found next to the label "Control Number" on your proxy card or voting instruction form. We recommend logging in at least 15 minutes before the meeting to ensure that you are logged in when the meeting starts. The Notice of the 2026 Annual Meeting of Shareholders, 2026 Proxy Statement, and 2025 Annual Report are available at https://ir.blackhillscorp.com/financial-information/annual-reports-proxy.

Proposals:

Election of three directors in Class II: Scott M. Prochazka, Teresa A. Taylor, and Anne G. Waleski.

Ratification of Deloitte & Touche LLP to serve as our independent registered public accounting firm for 2026.

Advisory vote to approve our executive compensation.

Any other business that properly comes before the annual meeting.

Record Date:

The Board set March 10, 2026 as the record date for the meeting. This means that our shareholders as of the close of business on that date are entitled to receive this notice of the meeting and vote at the meeting and any adjournments or postponements of the meeting.

How to Vote by Proxy:

Your vote is very important. You may vote your shares by telephone, by the internet or by returning the enclosed proxy. If you own shares of common stock other than the shares shown on the enclosed proxy, you will receive a proxy in a separate envelope for each such holding. Please vote each proxy received. To make sure that your vote is counted if voting by mail, you should allow enough time for the postal service to deliver your proxy before the meeting.

Sincerely,

/s/ DARREN NAKATA

Darren Nakata

Senior Vice President - Chief Legal Officer, Corporate Secretary and Chief Compliance Officer

PROXY SUMMARY

BLACK HILLS CORPORATION OVERVIEW

We are a customer-focused energy solution provider that invests in our communities’ safety, sustainability and growth with a mission of Improving Life with Energyand a vision to be the Energy Partner of Choice. The Company’s core mission – and our primary focus – is to provide safe, reliable and cost-effective electric and natural gas service to more than 1.37 million utility customers in over 800 communities in eight states, including Arkansas, Colorado, Iowa, Kansas, Montana, Nebraska, South Dakota and Wyoming.

MERGER WITH NORTHWESTERN ENERGY GROUP, INC.

On August 19, 2025, Black Hills Corporation ("Black Hills") and NorthWestern Energy Group, Inc. ("NorthWestern") announced a definitive agreement to combine in an all-stock, tax-free merger (the "Merger") that will create a premier regional regulated electric and natural gas utility company.

Under the terms of the agreement, NorthWestern shareholders will receive a fixed exchange ratio of 0.98 shares of Black Hills for each share of NorthWestern they own at the close of the transaction. The exchange ratio implies an approximately 4% premium based on the volume weighted average price of each company’s common stock since Black Hills and NorthWestern began discussing transaction terms in March 2025. Black Hills shareholders will continue to hold the same number of shares of the combined company that they hold of Black Hills immediately prior to the closing of the transaction. Upon completion of the Merger, Black Hills shareholders will own approximately 56% and NorthWestern shareholders will own approximately 44% of the combined company on a fully diluted basis.

Additional information related to the Merger can be found in the Form S-4 Registration Statement filed with the Securities and Exchange Commission on January 30, 2026. A virtual only Special Meeting of Shareholders will be held on Thursday, April 2, 2026 at 10:00 a.m. (MT) for shareholders of record as of January 28, 2026.

Items of Business to be Considered at the Annual Meeting

BOARD OF DIRECTORS

Director Nominees

Our Board of Directors ("Board") is committed to oversight that promotes the long-term interests of our shareholders and other stakeholders. We believe this is best achieved with directors who bring a diverse and relevant set of skills, expertise, experiences and perspectives. Our Board is nominating three individuals for election at this annual meeting, all of whom are currently serving on our Board. The following table provides summary information about the nominees:

Proxy Summary ‖1

Director Skills and Demographics

OUR COMMITMENT TO SUSTAINABILITY

Our mission of Improving Life with Energy means we must be ready to make tomorrow even better than today. That is why we are committed to creating a cleaner energy future which builds upon our responsibility to provide the safe, reliable and cost-effective energy that improves our customers’ lives. By investing in the success of our employees, continually innovating, thoughtfully utilizing resources and keeping people at the core of our decision-making, we are dedicated to the sustainability of our Company and communities.

Sustainability Oversight

We are continuously building upon our success of delivering cost-effective energy for customers and strong returns for investors by seeking renewable energy growth opportunities, minimizing risk and responding to stakeholders’ evolving expectations. Sustainability is inherently connected throughout our business and our management of related initiatives is structured accordingly. Our Board oversees our Environmental, Social, and Governance (ESG) strategy, with management leadership from our CEO and executive steering committee, our dedicated department and our cross functional sustainability working group.

Responsibly Reducing Greenhouse Gas Emissions

We have set challenging, yet realistic, goals for delivering cleaner energy. We have reduced our electric utilities' greenhouse gas emissions intensity by 38% since 2005 through the addition of renewables, natural gas, and retirement of aging coal plants. We have reduced our natural gas utility emissions 11% since 2022, making significant progress towards our net zero by 2035 target for our natural gas utilities.

Proxy Summary ‖2

(1)

Our goals are compared to a 2005 baseline.

(2)

Electric Utilities goals include Scope 1 emissions from electric utility generating units and Scope 3 emissions from purchased power for sales.

(3)

Natural Gas Utilities goals include all Scope 1 sources of methane emissions on our distribution system, including fugitive emissions from pipeline mains and service lines, meters, transfer stations, system damages and system blow downs.

We will continue executing our strategy of investing in cost-effective renewables and new technologies to further reduce our environmental impact across all states in which we operate, while continuing to deliver safe, reliable and cost effective energy to customers.

For additional information on our commitment to sustainability, you can review the following 2024 ESG reports on our website atwww.blackhillsenergy.com/our-company/commitment-sustainability/sustainability-and-esg-reports.

OUR COMMITMENT TO WILDFIRE SAFETY AND PREVENTION

We have a long history of delivering safe and reliable energy to our customers. For decades, we have employed a wide variety of wildfire mitigation measures and initiatives to support the integrity of our energy delivery systems, while safeguarding our facilities and the surrounding environment. These efforts are part of our comprehensive approach to mitigate not only wildfire risk, but also a variety of extreme weather events, including ice storms and high winds. We are utilizing a three-pronged approach to wildfire mitigation, which includes the following:

•

Asset programs like preventative inspection, repair, and maintenance practices, including vegetation management, line patrol in the air and on the ground, and pole inspections and replacement.

•

Integrity programs and system investments aimed at improving reliability and reducing risk, undergrounding electric distribution lines, and applying construction standards that reduce the likelihood of wildfire interactions with facilities.

•

Operational response utilizing risk-driven decisions including system reconfigurations, daily work activities and equipment operation (non-reclosing energized power lines), and fire weather forecasting tools to enhance situational awareness and understanding of a potentially hazardous fire area.

Emergency Public Safety Power Shutoff

We are committed to the ongoing development and implementation of risk reduction strategies for the betterment of the environment and our customers, employees, and investors. In 2025, we established the Emergency Public Safety Power Shutoff ("PSPS") program within our service territories. The PSPS involves selectively and proactively de-energizing powerlines in high-risk fire areas to mitigate the risk that electric facilities become a source of wildfire ignition.

For additional information on our commitment to wildfire safety and prevention, please visit our website atwww.blackhillsenergy.com/safety/wildfire-safety-and-prevention.

EXECUTIVE COMPENSATION

We have an Executive Compensation Philosophy that establishes the framework our Leadership Development and Compensation Committee applies in structuring compensation for our executive officers ("Named Executive Officers" or "NEOs"). The components of our executive pay program consist of a base salary, a short-term incentive plan, and long-term incentives. Our executive pay program aligns the interest of our Named Executive Officers with our stakeholders by tying incentive pay to achievement of performance metrics.

Proxy Summary ‖3

(1) Mr. Casey's employment was involuntarily terminated on April 1, 2025, and therefore was not eligible for short-term incentive compensation in 2025. Mr. Redden was hired on July 21, 2025 and was eligible for a prorated short-term incentive but was not eligible for a long-term incentive in 2025.

The performance measures for our incentive compensation plans are discussed in greater detail on page 27 of the Proxy Statement. We also require our executive officers to hold a significant amount of our common stock (between 3 and 6 times base salary) to further align their interests with the interest of our stakeholders.

Our compensation practices and policies demonstrate the alignment between executive compensation and the interests of our stakeholders. Our shareholders share our confidence in our compensation philosophy as reflected by the support of shareholders owning 97.8 percent of the shares who voted to approve our 2024 executive compensation at last year's annual meeting.

Proxy Summary ‖4

Proxy Summary ‖5

7001 Mount Rushmore Road

Rapid City, South Dakota 57702

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