SRSTOCK RADAR
Filings/Analysis
SEC EDGARFiled May 19, 2026 - 7:11 AM ET

Universal shelf with $183.4M ATM capacity carried forward

NYSE:BKHBLACK HILLS CORP /SD/S-3bearishImpact 59

BKH Price

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N/A$0.00 (+0.00%)
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Dilution Snapshot

Current shares76,128,592 sharesOutstanding share count from offering terms.
Registered shares183,376,179.78 sharesPotential supply.
Supply / current240.9%Potential supply compared with current shares.
Company proceeds$183,376,179.78Gross proceeds from disclosed primary offering terms.

Creates capacity to issue shares via ATM, which could increase tradable supply if used; immediate dilution depends on future sales

Black Hills filed an automatic universal shelf registration that carries forward $183,376,179.78 of common-stock capacity previously reserved for its at-the-market (ATM) program. That dollar figure is registration capacity only — shares and per-share offering prices are not disclosed here — so the immediate share impact is unknown. If the company sells shares under the ATM, those sales would be newly issued shares that increase tradable supply and provide company cash proceeds; absent sales, this filing only creates optionality. Key uncertainties: no registered share count or ATM daily/aggregate share limits disclosed; follow prospectus supplements or 424(b) notices for any concrete takedown or sale schedule.

The key follow-up variable is Registration effectiveness and filing date.

Share Overhang

Current shares plus potential supply

Low240.9%Total potential dilution vs. current shares
ACurrent shares76.13MBRegistered shares183.38M
A. Current sharesReference76.13MB. Registered sharesReference183.38M(240.9% of current shares)
Total Potential Overhang183.38M/76.13M=240.9%potential supply vs. current shares

Share counts are filing-stated unless noted and may differ after splits, conversions, or later offerings.

Supply Details

Current Shares Outstanding76.13M
Registered Shares183.38M
Total Overhang240.9%
Overhang LevelLow

Breakdown

% of current
Registered shares183.38M240.9%

High share overhang may create selling pressure. Monitor warrant exercise and note conversion activity.

BKH Market Context

Market Cap$5.64B
Shares Outstanding76.13M
Public Float75.72M
Public Float %99.5%

Original Filing Text

SEC filing text preserved from the raw item store.

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TABLE OF CONTENTS

As filed with the Securities and Exchange Commission on May 19, 2026

Registration No. 333-        ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

BLACK HILLS CORPORATION

(Exact name of registrant as specified in its charter)

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South Dakota

(State or other jurisdiction of

incorporation or organization) ​

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46-0458824

(I.R.S. Employer

Identification Number)

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7001 Mount Rushmore Road

Rapid City, South Dakota

57702 (605) 721-1700

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Darren Nakata

Senior Vice President — Chief Legal Officer

7001 Mount Rushmore Road

Rapid City, South Dakota 57702

(605) 721-1700

(Name, address, including zip code, and telephone number, including area code, of agent for service)

WITH COPIES TO:

Brandon C. Mason, Esq.

Faegre Drinker Biddle & Reath LLP

2200 Wells Fargo Center

90 South Seventh Street

Minneapolis, Minnesota 55402

(612) 766-7000

Approximate date of commencement of proposed sale to the public:

From time to time after the effective date of this registration statement.

If the only securities being registered on this form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. ☐

If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ☒

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☒

If this form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b 2 of the Exchange Act. (Check one):

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Large accelerated filer ☒
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Accelerated filer ☐

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Non-accelerated filer ☐

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Smaller reporting company ☐

Emerging growth company ☐

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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 7(a)(2)(B) of the Securities Act. ☐

TABLE OF CONTENTS

PROSPECTUS

BLACK HILLS CORPORATION

Senior Debt Securities

Subordinated Debt Securities

Preferred Stock

Depositary Shares

Common Stock

Warrants

Purchase Contracts

Units

We may from time to time offer to sell senior debt securities, subordinated debt securities, preferred stock, depositary shares, common stock, warrants, purchase contracts or units. Each time we sell securities pursuant to this prospectus, we will provide a supplement to this prospectus that contains specific information about the offering and the specific terms of the securities offered. You should read this prospectus and the applicable prospectus supplement carefully before you invest in our securities.

Our common stock is currently listed on the New York Stock Exchange under the symbol “BKH.”

There are significant risks associated with an investment in our securities. You should read carefully the risks we describe on page  4 of this prospectus, as well as the risk factors in the accompanying prospectus supplement and discussed in our periodic reports that we file with the Securities and Exchange Commission, for a better understanding of the risks and uncertainties that investors in our securities should consider.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

The date of this prospectus is May 19, 2026.

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TABLE OF CONTENTS

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Page

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About This Prospectus

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1
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Disclosure Regarding Forward-Looking Statements

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Black Hills Corporation

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Risk Factors

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Use of Proceeds

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5
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Description of Senior Debt Securities

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Description of Subordinated Debt Securities

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Description of Capital Stock

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Description of Warrants

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Description of Purchase Contracts

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Description of Units

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Plan of Distribution

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Legal Opinions

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Experts

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Where You Can Find More Information

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We are responsible only for the information contained in this prospectus, the applicable prospectus supplement, or any free writing prospectus to which we have referred you. We have not authorized any other person to provide you with different or additional information and we take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. Further, you should not assume that the information contained or incorporated by reference in this prospectus, any prospectus supplement, or any such free writing prospectus, or in any document incorporated by reference is accurate as of any date other than the respective dates thereof. Our business, financial condition, results of operations and prospects may have changed since those dates. This prospectus may only be used where it is legal to offer and sell these securities.

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, or the “SEC,” utilizing a “shelf” registration process. Under this shelf process, we may, from time to time, sell any combination of the securities described in this prospectus in one or more offerings. For further information about our business and the securities, you should refer to the registration statement and its exhibits. The exhibits to the registration statement and the documents incorporated by reference in the registration statement contain the full text of the contracts and other important documents summarized in this prospectus. Since these summaries may not contain all the information that you may find important in deciding whether to purchase the securities that we may offer, you should review the full text of these documents. The registration statement can be obtained from the SEC as indicated under the heading “Where You Can Find More Information.”

This prospectus provides you with only a general description of the securities we may offer. Each time we offer to sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update, or change information contained in this prospectus. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement, you should rely on the information in the prospectus supplement. You should read both this prospectus and the applicable prospectus supplement together with the additional information described under the heading “Where You Can Find More Information.”

When we refer to “Black Hills,” “the Company,” “we,” “us” and “our” in this prospectus under the headings “Disclosure Regarding Forward-Looking Statements” and “Black Hills Corporation,” we mean Black Hills Corporation, a South Dakota corporation, and all of its subsidiaries collectively unless the context indicates otherwise. When such terms are used elsewhere in this prospectus, we refer only to Black Hills Corporation (parent company only) and not any of its subsidiaries unless the context indicates otherwise.

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DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, the applicable prospectus supplement and the documents incorporated by reference herein and therein may include forward-looking statements as defined by the SEC. We make these forward-looking statements in reliance on the safe harbor protections provided under the Private Securities Litigation Reform Act of 1995. Forward-looking statements are all statements other than statements of historical fact, including, without limitation, those statements that are identified by the words “anticipates,” “estimates,” “expects,” “intends,” “plans,” “predicts” and similar expressions, and include statements concerning plans, objectives, goals, strategies, future events or performance, and underlying assumptions and other statements that are other than statements of historical facts.

Forward-looking statements involve risks and uncertainties, which could cause actual results or outcomes to differ materially from those expressed. Our expectations, beliefs and projections are expressed in good faith and are believed by us to have a reasonable basis, including, without limitation, management’s examination of historical operating trends, data contained in the Company’s records and other data available from third parties. Nonetheless, the Company’s expectations, beliefs or projections may not be achieved or accomplished.

Any forward-looking statement contained in this document speaks only as of the date on which the statement is made, and we undertake no obligation to update any forward-looking statement or statements to reflect events or circumstances that occur after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, such as adverse macroeconomic conditions, global pandemics or severe weather events, and it is not possible for management to predict all of the factors, nor can it assess the effect of each factor on the Company’s business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statement. All forward-looking statements, whether written or oral and whether made by or on behalf of the Company, are expressly qualified by the risk factors and cautionary statements set forth in Item 1A of Part I of our Annual Report on Form 10-K for the year ended December 31, 2025 , and in other reports that we file with the SEC from time to time.

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BLACK HILLS CORPORATION

Black Hills Corporation, a South Dakota corporation, is a customer-focused, growth-oriented utility company headquartered in Rapid City, South Dakota.

We operate our business in the United States, reporting our operating results through our Electric Utilities and Gas Utilities segments. Certain unallocated corporate expenses that support our operating segments are presented as Corporate and Other. The following paragraphs summarize information about our segments as of December 31, 2025.

Our Electric Utilities segment generates, transmits and distributes electricity to approximately 227,000 electric utility customers in Colorado, Montana, South Dakota, and Wyoming. Our Electric Utilities own 1,386 MW of generation and 9,478 miles of electric transmission and distribution lines.

Our Gas Utilities segment serves approximately 1,138,000 natural gas utility customers in Arkansas, Colorado, Iowa, Kansas, Nebraska, and Wyoming. Our Gas Utilities own and operate 4,581 miles of intrastate gas transmission pipelines and 44,840 miles of gas distribution mains and service lines, seven natural gas storage sites, more than 50,000 horsepower of compression, and 494 miles of gathering lines.

NorthWestern Energy Merger

On August 18, 2025, we entered into a definitive agreement with NorthWestern Energy Group, Inc. (“NorthWestern”) to combine in a tax-free, all-stock merger of equals (the “Merger”). NorthWestern, 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 its customers and communities. NorthWestern provides electricity and/or natural gas to approximately 850,300 customers in Montana, South Dakota, Nebraska, and Yellowstone National Park. The merger agreement, by and among Black Hills, our wholly owned subsidiary River Merger Sub Inc. (“Merger Sub”) and NorthWestern, provides for Merger Sub to merge with and into NorthWestern, with NorthWestern continuing as the surviving entity and our direct wholly owned subsidiary. As the resulting parent company of the combined corporate group, we would assume the new corporate name of Bright Horizon Energy, Inc. and adopt a new stock ticker. The combined company will serve approximately 0.7 million electric utility customers and 1.5 million gas utility customers across eight states. At the effective time of the Merger, each share of common stock of NorthWestern, par value $0.01 per share, issued and outstanding as of immediately prior to the effective time will be converted into the right to receive 0.98 validly issued, fully paid and non-assessable shares of our common stock, par value $1.00 per share (or cash-in-lieu of fractional shares thereof). The Merger, which is currently expected to close in the second half of 2026, has been approved by the shareholders of each of Black Hills and NorthWestern but remains subject to certain regulatory approvals and other customary closing conditions. For more information about the Merger, please refer to the information included in our periodic and current reports described under the heading “Where You Can Find More Information.”

Other Information

Our common stock is currently listed on the New York Stock Exchange under the symbol “BKH.” Our principal and executive offices are located at 7001 Mount Rushmore Road, Rapid City, South Dakota 57702 and our telephone number is (605) 721-1700. Our Internet address is www.blackhillscorp.com . Information on our website does not constitute part of this prospectus.

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RISK FACTORS

Please carefully consider all of the information contained in or incorporated by reference in this prospectus, including the risk factors described in our periodic reports filed with the SEC from time to time, including those set forth under the caption “Risk Factors” in Item 1A of Part I of our Annual Report on Form 10-K for the year ended December 31, 2025 , which are incorporated by reference in this prospectus. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus or include in any applicable prospectus supplement or free writing prospectus.

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USE OF PROCEEDS

Unless otherwise indicated in the applicable prospectus supplement, we intend to use the net proceeds from the sale of any securities described in this prospectus for working capital and general corporate purposes, which may include:

repayment or refinancing of outstanding debt;

capital expenditures;

acquisitions;

investments;

shareholder returns; and

other business opportunities.

We will have significant discretion in the use of the net proceeds. Until the net proceeds have been used for their intended purposes, they may be held in cash or cash equivalents or temporarily used or invested.

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DESCRIPTION OF SENIOR DEBT SECURITIES

General

The following description applies to the senior debt securities offered by this prospectus. The senior debt securities will be direct, unsecured obligations of Black Hills and will rank on a parity with all of our outstanding unsecured senior indebtedness. The senior debt securities may be issued in one or more series. The senior debt securities will be issued under the indenture dated May 21, 2003 between us and the trustee (which was originally LaSalle Bank National Association and is now Computershare Trust Company, N.A.).

The statements under this caption are brief summaries of the provisions contained in the indenture, do not claim to be complete and are qualified in their entirety by reference to the indenture, a copy of which is filed as an exhibit to the registration statement of which this prospectus forms a part. Whenever defined terms are used but not defined in this prospectus, those terms have the meanings given to them in the indenture.

The following describes the general terms and provisions of the senior debt securities to which any prospectus supplement may relate. The particular terms of any senior debt security and the extent, if any, to which these general provisions may apply to the senior debt securities will be described in the prospectus supplement relating to the senior debt securities.

The indenture does not limit the aggregate principal amount of senior debt securities which may be issued under it. Rather, the indenture provides that senior debt securities of any series may be issued under it up to the aggregate principal amount which we may authorize from time to time. Senior debt securities may be denominated in any currency or currency unit we designate. Neither the indenture nor the senior debt securities will limit or otherwise restrict the amount of other debt which we may incur or the other securities which we may issue.

While the senior debt securities will be our unsecured senior obligations, our assets consist primarily of equity in our subsidiaries. We are a separate and distinct legal entity from our subsidiaries. As a result, our ability to make payments on our senior debt securities depends on our receipt of dividends, loan payments and other funds from our subsidiaries. Various federal and state statutes and regulations, including the Federal Power Act and settlement agreements with state regulatory jurisdictions, limit the amount of dividends that may be paid to us as a utility holding company.

In addition, if any of our subsidiaries becomes insolvent, the direct creditors of that subsidiary will have a prior claim on its assets. Holders of the senior debt securities are not creditors of our subsidiaries. The claims of holders of the senior debt securities to the assets of our subsidiaries derive from our own equity interests in those subsidiaries. Claims of such subsidiaries’ creditors will generally have priority as to the assets of such subsidiaries over our own equity interest claims and will therefore have priority over the holders of the senior debt securities. Our subsidiaries’ creditors may include general creditors, trade creditors, debt holders, any preferred stockholders and taxing authorities. The subordination of creditors of a parent company to prior claims of creditors of its subsidiaries is commonly referred to as structural subordination.

Senior debt securities of a series may be issuable in registered form without coupons, which we refer to as “registered securities,” or in the form of one or more global securities in registered form, which we refer to as “global securities.”

You must review the prospectus supplement for a description of the following terms, where applicable, of each series of senior debt securities for which this prospectus is being delivered:

the title of the senior debt securities;

the limit, if any, on the aggregate principal amount or aggregate initial public offering price of the senior debt securities;

the priority of payment of the senior debt securities;

the price or prices, which may be expressed as a percentage of the aggregate principal amount, at which the senior debt securities will be issued;

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the date or dates on which the principal of the senior debt securities will be payable;

the interest rate or rates, which may be fixed or variable, for the senior debt securities, if any, or the method of determining the same;

the date or dates from which interest, if any, on the senior debt securities will accrue, the date or dates on which interest, if any, will be payable, the date or dates on which payment of interest, if any, will commence and the regular record dates for the interest payment dates;

the extent to which any of the senior debt securities will be issuable in temporary or permanent global form, or the manner in which any interest payable on a temporary or permanent global senior debt security will be paid;

each office or agency where the senior debt securities may be presented for registration of transfer or exchange;

the place or places where the principal of and any premium and interest on the senior debt securities will be payable;

the date or dates, if any, after which the senior debt securities may be redeemed or purchased in whole or in part, (1) at our option, or (2) mandatorily pursuant to any sinking, purchase or similar fund, or (3) at the option of the holder, and the redemption or repayment price or prices;

the terms, if any, upon which the senior debt securities may be convertible into or exchanged for any other kind of our securities or indebtedness and the terms and conditions upon which the conversion or exchange would be made, including the initial conversion or exchange price or rate, the conversion period and any other additional provisions;

the authorized denomination or denominations for the senior debt securities;

the currency, currencies or units based on or related to currencies for which the senior debt securities may be purchased and the currency, currencies or currency units in which the principal of and any premium and interest on the senior debt securities may be payable;

any index used to determine the amount of payments of principal of and any premium and interest on the senior debt securities;

the payment of any additional amounts with respect to the senior debt securities;

whether any of the senior debt securities will be issued with original issue discount;

information with respect to book-entry procedures, if any;

any additional covenants or events of default not currently included in the indenture relating to the senior debt securities; and

any other terms of the senior debt securities not inconsistent with the provisions of the indenture.

If any of the senior debt securities are sold for one or more foreign currencies or foreign currency units or if the principal of or any premium or interest on any series of senior debt securities is payable in one or more foreign currencies or foreign currency units, the restrictions, elections, tax consequences, specific terms and other information with respect to that issue of senior debt securities and those currencies or currency units will be described in the applicable prospectus supplement.

A judgment for money damages by courts in the United States, including a money judgment based on an obligation expressed in a foreign currency, will ordinarily be rendered only in U.S. dollars. New York statutory law provides that a court shall render a judgment or decree in the foreign currency of the underlying obligation and that the judgment or decree shall be converted into U.S. dollars at the exchange rate prevailing on the date of entry of the judgment or decree.

Senior debt securities may be issued as original issue discount senior debt securities, which bear no interest or interest at a rate which at the time of issuance is below market rates, to be sold at a substantial discount below their stated principal amount due at the stated maturity of the senior debt securities. There may be no periodic payments of interest on original issue discount securities. In the event of an acceleration

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of the maturity of any original issue discount security, the amount payable to the holder of the original issue discount security upon such acceleration will be determined in accordance with the applicable prospectus supplement, the terms of the security and the indenture, but will be an amount less than the amount payable at the maturity of the principal of the original issue discount security.

If the senior debt securities are issued with “original issue discount” within the meaning of the Internal Revenue Code of 1986, as amended, then a holder of those senior debt securities will be required under the Internal Revenue Code to include original issue discount in ordinary income for federal income tax purposes as it accrues, in accordance with a constant interest method that takes into account the compounding of interest, in advance of receipt of cash attributable to that income. Generally, the total amount of original issue discount on a senior debt security will be the excess of the stated redemption price at maturity of the security over the price at which the security is sold to the public. To the extent a holder of a senior debt security receives a payment (at the time of acceleration of maturity, for example) that represents payment of original issue discount already included by the holder in ordinary income or reflected in the holder’s tax basis in the security, that holder generally will not be required to include the payment in income. The specific terms of any senior debt securities that are issued with original issue discount and the application of the original discount rules under the Internal Revenue Code to those securities will be described in the prospectus supplement for those securities.

Registration and Transfer

Unless otherwise indicated in the applicable prospectus supplement, senior debt securities will be issued only as registered securities. Senior debt securities issued as registered securities will not have interest coupons.

Registered securities (other than a global security) may be presented for transfer, with the form of transfer endorsed thereon duly executed, or exchanged for other senior debt securities of the same series at the office of the security registrar specified in the indenture. The indenture provides that we will cause a register to be kept at the Corporate Trust Office and in the applicable place of payment for such transfer or exchange. Transfer or exchange will be made without service charge, but we may require payment of any taxes or other governmental charges.

Book-Entry Senior Debt Securities

Senior debt securities of a series may be issued in whole or in part in the form of one or more global securities. Each global security will be deposited with, or on behalf of, a depositary identified in the applicable prospectus supplement. Global securities will be issued in registered form and in either temporary or permanent form. Until exchanged in whole or in part for the individual securities which it represents, a global security may not be transferred except as a whole by the depositary for the global security to a nominee of the depositary or by a nominee of the depositary to the depositary or another nominee of the depositary or by the depositary or any nominee to a successor depositary or any nominee of the successor. The specific terms of the depositary arrangement for a series of senior debt securities will be described in the applicable prospectus supplement.

Payment and Paying Agents

Unless otherwise indicated in an applicable prospectus supplement, payment of principal of and any premium and interest on registered securities will be made at the office of such paying agent or paying agents as we may designate from time to time. In addition, at our option, payment of any interest may be made by:

check mailed to the address of the person entitled to the payment at the address in the applicable security register; or

wire transfer to an account maintained by the person entitled to the payment as specified in the applicable security register.

Unless otherwise indicated in an applicable prospectus supplement, payment of any installment of interest on registered securities will be made to the person in whose name the senior debt security is registered at the close of business on the regular record date for the payment.

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Consolidation, Merger or Sale of Assets

The indenture relating to the senior debt securities provides that we may, without the consent of the holders of any of the senior debt securities outstanding under the indenture, consolidate with, merge into or transfer our assets substantially as an entirety to any person, provided that:

any successor assumes our obligations on the senior debt securities and under the indenture; and

after giving effect to the consolidation, merger or transfer, no event of default (as defined in the indenture) will have happened and be continuing.

Any consolidation, merger or transfer of assets substantially as an entirety, which meets the conditions described above, would not create an event of default which would entitle holders of the senior debt securities, or the trustee acting on their behalf, to take any of the actions described below under “— Events of Default, Waivers, Etc.”

Leveraged and Other Transactions

The indenture and the senior debt securities do not contain provisions which would protect holders of the senior debt securities in the event we engaged in a highly leveraged or other transaction which could adversely affect the holders of senior debt securities.

Modification of the Indenture

The indenture provides that, with the consent of the holders of not less than a majority in aggregate principal amount of the outstanding senior debt securities of each affected series, modifications and alterations of the indenture may be made which affect the rights of the holders of the senior debt securities. However, no modification or alteration may be made without the consent of the holder of each senior debt security affected which would, among other things:

modify the terms of payment of principal of or any premium or interest on the senior debt securities; or

reduce the percentage in principal amount of outstanding senior debt securities required to modify or alter the indenture.

Events of Default, Waivers, Etc.

An “event of default” with respect to senior debt securities of any series is defined in the indenture to include, among other things:

(1)

default in the payment of principal of or any premium on any of the outstanding senior debt securities of that series when due;

(2)

default in the payment of interest on any of the outstanding senior debt securities of that series when due and continuance of such default for 30 days;

(3)

default in the performance of any of our other covenants in the indenture with respect to the senior debt securities of that series and continuance of such default for 60 days after written notice;

(4)

certain events of bankruptcy, insolvency or reorganization relating to us; and

(5)

any other event that may be specified in the applicable prospectus supplement with respect to any series of senior debt securities.

If an event of default with respect to any series of outstanding senior debt securities occurs and is continuing, either the trustee or the holders of not less than 25% in aggregate principal amount of the outstanding senior debt securities of that series may declare the principal amount (or with respect to original issue discount securities, the portion of the principal amount as may be specified in the terms of that series) of all senior debt securities of that series to be immediately due and payable. The holders of a majority in aggregate principal amount of the outstanding senior debt securities of any series may waive an event of default resulting in acceleration of the senior debt securities, but only if all events of default with respect to

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senior debt securities of such series have been remedied and all payments due, other than those due as a result of acceleration, have been made.

If an event of default occurs and is continuing, the trustee may, in its discretion, and at the written request of holders of not less than a majority in aggregate principal amount of the outstanding senior debt securities of any series and upon reasonable indemnity against the costs, expenses and liabilities to be incurred in compliance with such request and subject to certain other conditions set forth in the indenture will, proceed to protect the rights of the holders of all the senior debt securities of that series. Prior to acceleration of maturity of the outstanding senior debt securities of any series, the holders of a majority in aggregate principal amount of the senior debt securities may waive any past default under the indenture except a default in the payment of principal of or any premium or interest on the senior debt securities of that series.

The indenture provides that upon the occurrence of an event of default specified in clauses (1) or (2) of the first paragraph in this subsection, we will, upon demand of the trustee, pay to it, for the benefit of the holders of any senior debt securities, the whole amount then due and payable on the affected senior debt securities for principal, premium, if any, and interest, if any. The indenture further provides that if we fail to pay such amount upon demand, the trustee may, among other things, institute a judicial proceeding for the collection of those amounts.

The indenture also provides that, notwithstanding any of its other provisions, the holder of any senior debt security of any series will have the right to institute suit for the enforcement of any payment of principal of or any premium or interest on the senior debt securities when due and that such right will not be impaired without the consent of that holder.

We are required to file annually with the trustee a written statement of our officers as to the existence or non-existence of defaults under the indenture or the senior debt securities.

Satisfaction and Discharge and Defeasance

The indenture provides, among other things, that when all senior debt securities not previously delivered to the trustee for cancellation (1) have become due and payable or (2) will become due and payable at their stated maturity (or be called for redemption) within one year, we may deposit with the trustee funds, in trust, for the purpose and in an amount sufficient to pay and discharge the entire indebtedness on the senior debt securities not previously delivered to the trustee for cancellation. Those funds will include all principal, premium, if any, and interest, if any, to the date of the deposit or to the stated maturity, as applicable. Upon such deposit, the indenture will cease to be of further effect except as to our obligations to pay all other sums due under the indenture and to provide the officers’ certificates and opinions of counsel required under the indenture. At such time, we will be deemed to have satisfied and discharged the indenture.

In addition, at the time that we establish a series of senior debt securities under the indenture, we can provide that the senior debt securities are subject to the defeasance and discharge provisions of the indenture. Unless we specify otherwise in the applicable prospectus supplement, the senior debt securities offered thereby will be subject to the defeasance and discharge provisions of the applicable indenture, and we may elect either (1) to defease and be discharged from any and all obligations with respect to the senior debt securities of a series (except for, among other things, obligations to register the transfer or exchange of the debt securities, to replace temporary or mutilated, destroyed, lost or stolen debt securities, to maintain an office or agency with respect to the debt securities and to hold moneys for payment in trust) (“legal defeasance”) or (2) to be released from our obligations to comply with the restrictive covenants we designate when we establish the series of senior debt securities, and any omission to comply with such obligations will not constitute a default or an event of default with respect to such senior debt securities (“covenant defeasance”). Legal defeasance or covenant defeasance, as the case may be, will be conditioned upon, among other things, the irrevocable deposit by us with the trustee, in trust, of an amount in U.S. dollars, or U.S. government obligations, or both, applicable to the debt securities of that series which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal or premium, if any, and interest, if any, on the senior debt securities on the scheduled due dates therefor.

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If we effect covenant defeasance with respect to any series of senior debt securities, the amount in money, or U.S. government obligations, or both, on deposit with the trustee will be sufficient, in the opinion of a nationally recognized firm of independent accountants, to pay amounts due on the senior debt securities of that series in accordance with the terms of the indenture and such senior debt securities.

We will be required to deliver to the trustee an opinion of counsel that the deposit and related defeasance will not cause the holders and beneficial owners of the senior debt securities of that series to recognize income, gain or loss for U.S. federal income tax purposes. If we elect legal defeasance, that opinion of counsel must be based upon a ruling from the U.S. Internal Revenue Service or a change in law to that effect.

We may exercise our legal defeasance option notwithstanding our prior exercise of our covenant defeasance option.

Governing Law

The indenture and the senior debt securities will be governed by, and construed in accordance with, the laws of the State of New York.

Regarding the Trustee

Computershare Trust Company, N.A., is the trustee under the indenture for the senior debt securities. The trustee and any agents under the indenture may resign or be removed and a successor may be appointed.

The trustee under the indenture for the senior debt securities and its affiliates have engaged, currently engage, and may in the future engage in transactions, including commercial banking and other transactions, with us and our subsidiaries from time to time, subject to the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”). An affiliate of the senior trustee may act as underwriter with respect to one or more series of senior debt securities. Consequently, if an actual or potential event of default occurs with respect to any of our senior debt securities, the trustee may be considered to have a conflicting interest for purposes of the Trust Indenture Act. In that case, the trustee may be required to resign and we would be required to appoint a successor trustee. If the trustee resigns following a default or for any other reason, it may be difficult to identify and appoint a qualified successor trustee.

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DESCRIPTION OF SUBORDINATED DEBT SECURITIES

General

The following description applies to the subordinated debt securities (including junior subordinated debt securities) offered by this prospectus. The subordinated debt securities will be unsecured, subordinated obligations of Black Hills. The subordinated debt securities may be issued in one or more series. The subordinated debt securities will be issued under, and references in this section to the indenture refer to, the junior subordinated indenture dated November 23, 2015 between us and U.S. Bank Trust Company, National Association (as successor in interest to U.S. Bank National Association), as junior subordinated trustee.

The statements under this caption are brief summaries of the provisions contained in the indenture, do not claim to be complete and are qualified in their entirety by reference to the indenture, the form of which is filed as an exhibit to the registration statement of which this prospectus forms a part. Whenever defined terms are used but not defined in this prospectus, those terms have the meanings given to them in the indenture.

The following describes the general terms and provisions of the subordinated debt securities to which any prospectus supplement may relate. The particular terms of any subordinated debt security and the extent, if any, to which these general provisions may apply to the subordinated debt securities will be described in the prospectus supplement relating to the subordinated debt securities.

The indenture does not limit the aggregate principal amount of subordinated debt securities which may be issued under it. Rather, the indenture provides that subordinated debt securities of any series may be issued under it up to the aggregate principal amount which we may authorize from time to time. Subordinated debt securities may be denominated in any currency or currency unit we designate. Neither the indenture nor the subordinated debt securities will limit or otherwise restrict the amount of other debt which we may incur or the other securities which we may issue.

The subordinated debt securities will be our unsecured subordinated obligations. Our assets consist primarily of equity in our subsidiaries. We are a separate and distinct legal entity from our subsidiaries. As a result, our ability to make payments on our subordinated debt securities depends on our receipt of dividends, loan payments and other funds from our subsidiaries. Various federal and state statutes and regulations, including the Federal Power Act and settlement agreements with state regulatory jurisdictions, limit the amount of dividends that may be paid to us as a utility holding company.

In addition, if any of our subsidiaries becomes insolvent, the direct creditors of that subsidiary will have a prior claim on its assets. Holders of the subordinated debt securities are not creditors of our subsidiaries. The claims of holders of the subordinated debt securities to the assets of our subsidiaries derive from our own equity interests in those subsidiaries. Claims of such subsidiaries’ creditors will generally have priority as to the assets of such subsidiaries over our own equity interest claims and will therefore have priority over the holders of the subordinated debt securities. Our subsidiaries’ creditors may include general creditors, trade creditors, debt holders, any preferred stockholders and taxing authorities. The subordination of creditors of a parent company to prior claims of creditors of its subsidiaries is commonly referred to as structural subordination.

Subordinated debt securities of a series may be issuable in the form of registered securities or global securities.

You must review the prospectus supplement for a description of the following terms, where applicable, of each series of subordinated debt securities for which this prospectus is being delivered:

the title of the subordinated debt securities;

the limit, if any, on the aggregate principal amount or aggregate initial public offering price of the subordinated debt securities;

the priority of payment of the subordinated debt securities;

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the price or prices, which may be expressed as a percentage of the aggregate principal amount, at which the subordinated debt securities will be issued;

the date or dates on which the principal of the subordinated debt securities will be payable;

the interest rate or rates, which may be fixed or variable, for the subordinated debt securities, if any, or the method of determining the same;

the date or dates from which interest, if any, on the subordinated debt securities will accrue, the date or dates on which interest, if any, will be payable, the date or dates on which payment of interest, if any, will commence and the regular record dates for the interest payment dates;

the extent to which any of the subordinated debt securities will be issuable in temporary or permanent global form, or the manner in which any interest payable on a temporary or permanent global subordinated debt security will be paid;

each office or agency where the subordinated debt securities may be presented for registration of transfer or exchange;

the place or places where the principal of and any premium and interest on the subordinated debt securities will be payable;

the date or dates, if any, after which the subordinated debt securities may be redeemed or purchased in whole or in part, (1) at our option, or (2) mandatorily pursuant to any sinking, purchase or similar fund, or (3) at the option of the holder, and the redemption or repayment price or prices;

the terms, if any, upon which the subordinated debt securities may be convertible into or exchanged for any other kind of our securities or indebtedness and the terms and conditions upon which the conversion or exchange would be made, including the initial conversion or exchange price or rate, the conversion period and any other additional provisions;

the authorized denomination or denominations for the subordinated debt securities;

the currency, currencies or units based on or related to currencies for which the subordinated debt securities may be purchased and the currency, currencies or currency units in which the principal of and any premium and interest on the subordinated debt securities may be payable;

any index used to determine the amount of payments of principal of and any premium and interest on the subordinated debt securities;

the payment of any additional amounts with respect to the subordinated debt securities;

whether any of the subordinated debt securities will be issued with original issue discount;

information with respect to book-entry procedures, if any;

the terms of subordination;

any additional covenants or events of default not currently included in the indenture relating to the subordinated debt securities; and

any other terms of the subordinated debt securities not inconsistent with the provisions of the indenture.

If any of the subordinated debt securities are sold for one or more foreign currencies or foreign currency units or if the principal of or any premium or interest on any series of subordinated debt securities is payable in one or more foreign currencies or foreign currency units, the restrictions, elections, tax consequences, specific terms and other information with respect to that issue of subordinated debt securities and those currencies or currency units will be described in the applicable prospectus supplement.

A judgment for money damages by courts in the United States, including a money judgment based on an obligation expressed in a foreign currency, will ordinarily be rendered only in U.S. dollars. New York statutory law provides that a court shall render a judgment or decree in the foreign currency of the underlying obligation and that the judgment or decree shall be converted into U.S. dollars at the exchange rate prevailing on the date of entry of the judgment or decree.

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Subordinated debt securities may be issued as original issue discount securities, to be sold at a substantial discount below their stated principal amount due at the stated maturity of the subordinated debt securities. There may be no periodic payments of interest on original issue discount securities. In the event of an acceleration of the maturity of any original issue discount security, the amount payable to the holder of the original issue discount security upon such acceleration will be determined in accordance with the prospectus supplement, the terms of the security and the indenture, but will be an amount less than the amount payable at the maturity of the principal of the original issue discount security.

If the subordinated debt securities are issued with “original issue discount” within the meaning of the Internal Revenue Code of 1986, as amended, then a holder of those subordinated debt securities will be required under the Internal Revenue Code to include original issue discount in ordinary income for federal income tax purposes as it accrues, in accordance with a constant interest method that takes into account the compounding of interest, in advance of receipt of cash attributable to that income. Generally, the total amount of original issue discount on a subordinated debt security will be the excess of the stated redemption price at maturity of the security over the price at which the security is sold to the public. To the extent a holder of a subordinated debt security receives a payment (at the time of acceleration of maturity, for example) that represents payment of original issue discount already included by the holder in ordinary income or reflected in the holder’s tax basis in the security, that holder generally will not be required to include the payment in income. The specific terms of any subordinated debt securities that are issued with original issue discount and the application of the original discount rules under the Internal Revenue Code to those securities will be described in the prospectus supplement for those securities.

Registration and Transfer

Unless otherwise indicated in the applicable prospectus supplement, subordinated debt securities will be issued only as registered securities. Subordinated debt securities issued as registered securities will not have interest coupons.

Registered securities (other than a global security) may be presented for transfer, with the form of transfer endorsed thereon duly executed, or exchanged for other subordinated debt securities of the same series at the office of the security registrar specified in the indenture. The indenture provides that we will maintain a security register within the continental U.S. for such transfer or exchange. Transfer or exchange will be made without service charge, but we may require payment of any taxes or other governmental charges.

Book-Entry Subordinated Debt Securities

Subordinated debt securities of a series may be issued in whole or in part in the form of one or more global securities. Each global security will be deposited with, or on behalf of, a depositary identified in the applicable prospectus supplement. Global securities will be issued in registered form and in either temporary or permanent form. Until exchanged in whole or in part for the individual securities which it represents, a global security may not be transferred except as a whole by the depositary for the global security to a nominee of the depositary or by a nominee of the depositary to the depositary or another nominee of the depositary or by the depositary or any nominee to a successor depositary or any nominee of the successor. The specific terms of the depositary arrangement for a series of subordinated debt securities will be described in the applicable prospectus supplement.

Payment and Paying Agents

Unless otherwise indicated in an applicable prospectus supplement, payment of principal of and any premium and interest on registered securities will be made at the office of such paying agent or paying agents as we may designate from time to time. In addition, at our option, payment of any interest may be made by:

check mailed to the address of the person entitled to the payment at the address in the applicable security register; or

wire transfer to an account maintained by the person entitled to the payment as specified in the applicable security register.

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Unless otherwise indicated in an applicable prospectus supplement, payment of any installment of interest on registered securities will be made to the person in whose name the subordinated debt security is registered at the close of business on the regular record date for the payment.

Subordination

The subordinated debt securities will be subordinated and junior in right of payment to our senior indebtedness. Unless otherwise specified in the applicable prospectus supplement, “senior indebtedness” means the principal of, premium, if any, interest (including all interest accruing subsequent to the commencement of any bankruptcy or similar proceeding, whether or not a claim for post-petition interest is allowable as a claim in any such proceeding) and rent payable on or in connection with, and all fees, costs, expenses and other amounts accrued or due on or in connection with any of our indebtedness, whether outstanding on the date of the indenture or thereafter created, incurred, assumed, guaranteed or in effect guaranteed by us (including all deferrals, renewals, extensions or refundings of, or amendments, modifications or supplements to, the foregoing). However, senior indebtedness does not include our indebtedness to any of our subsidiaries or any particular indebtedness the instrument creating or evidencing the same or the assumption or guarantee thereof expressly provides that such indebtedness shall not be senior in right of payment to the subordinated debt securities or expressly provides that such indebtedness is “pari passu” or “junior” to the subordinated debt security.

Consolidation, Merger or Sale of Assets

The indenture provides that we may not merge or consolidate with any other person or sell or convey all or substantially all of our assets to any person unless (i) either we are the continuing person, or the successor (if other than us) is a corporation, limited liability company, partnership or trust organized and existing under the laws of the United States of America or a State thereof or the District of Columbia and such person expressly assumes the due and punctual payment of the principal of and interest on the subordinated debt securities, and the due and punctual performance and observance of all of the covenants and conditions of the indenture to be performed by us by supplemental indenture in form satisfactory to the indenture trustee, executed and delivered to the indenture trustee by such person, and (ii) immediately after giving effect to such merger or consolidation, or such sale or conveyance, no event of default, and no event which, after notice or lapse of time or both, would become an event of default, will occur and be continuing.

In case of any such consolidation, merger or conveyance, such successor will succeed to and be substituted for us, with the same effect as if it had been named as us in the indenture, and in the event of such conveyance (other than by way of a lease), we will be discharged of all of our obligations and covenants under the indenture and the subordinated debt securities.

Leveraged and Other Transactions

The indenture and the subordinated debt securities do not contain provisions which would protect holders of the subordinated debt securities in the event we engage in a highly leveraged or other transaction which could adversely affect the holders of subordinated debt securities.

Modification of the Indenture

The indenture provides that, with the consent of the holders of not less than a majority in aggregate principal amount of the outstanding subordinated debt securities of each affected series, modifications and alterations of the indenture may be made which affect the rights of the holders of the subordinated debt securities. However, no modification or alteration may be made without the consent of the holder of each subordinated debt security affected which would, among other things:

modify the terms of payment of principal of or any premium or interest on the subordinated debt securities;

adversely modify the subordination terms of the subordinated debt securities; or

reduce the percentage in principal amount of outstanding subordinated debt securities required to modify or alter the indenture.

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Events of Default, Waivers, Etc.

An “event of default” with respect to subordinated debt securities of any series is defined in the indenture to include:

(1)

default in the payment of principal of or any premium on any of the outstanding subordinated debt securities of that series when due;

(2)

default in the payment of interest on any of the outstanding subordinated debt securities of that series when due and continuance of such default for 30 days;

(3)

default in the performance of any of our other covenants in the indenture with respect to the subordinated debt securities of that series and continuance of such default for 90 days after written notice;

(4)

certain events of bankruptcy, insolvency or reorganization relating to us; and

(5)

any other event that may be specified in the prospectus supplement with respect to any series of subordinated debt securities.

If an event of default with respect to any series of outstanding subordinated debt securities occurs and is continuing, either the trustee or the holders of not less than 25% in aggregate principal amount of the outstanding subordinated debt securities of that series may declare the principal amount (or with respect to original issue discount securities, the portion of the principal amount as may be specified in the terms of that series) of all subordinated debt securities of that series to be immediately due and payable. The holders of a majority in aggregate principal amount of the outstanding subordinated debt securities of any series may waive an event of default resulting in acceleration of the subordinated debt securities, but only if all events of default with respect to subordinated debt securities of such series have been remedied and all payments due, other than those due as a result of acceleration, have been made.

If an event of default occurs and is continuing, the trustee may, in its discretion, and at the written request of holders of not less than a majority in aggregate principal amount of the outstanding subordinated debt securities of any series and upon reasonable indemnity against the costs, expenses and liabilities to be incurred in compliance with such request and subject to certain other conditions set forth in the indenture will, proceed to protect the rights of the holders of all the subordinated debt securities of that series. Prior to acceleration of maturity of the outstanding subordinated debt securities of any series, the holders of a majority in aggregate principal amount of the subordinated debt securities may waive any past default under the indenture except a default in the payment of principal of or any premium or interest on the subordinated debt securities of that series.

The indenture provides that upon the occurrence of an event of default specified in clauses (1) or (2) of the first paragraph in this subsection, we will, upon demand of the trustee, pay to it, for the benefit of the holders of any subordinated debt securities, the whole amount then due and payable on the affected subordinated debt securities for principal, premium, if any, and interest, if any. The indenture further provides that if we fail to pay such amount upon demand, the trustee may, among other things, institute a judicial proceeding for the collection of those amounts.

The indenture also provides that, notwithstanding any of its other provisions, the holder of any subordinated debt security of any series will have the right to institute suit for the enforcement of any payment of principal of or any premium or interest on the subordinated debt securities when due and that such right will not be impaired without the consent of that holder.

We are required to file annually with the trustee a written statement of our officers as to the existence or non-existence of defaults under the indenture or the subordinated debt securities.

Satisfaction and Discharge and Defeasance

The indenture provides, among other things, that when all subordinated debt securities not previously delivered to the trustee for cancellation (1) have become due and payable or (2) will become due and payable at their stated maturity (or called for redemption) within one year, we may deposit with the trustee funds,

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in trust, for the purpose and in an amount sufficient to pay and discharge the entire indebtedness on the subordinated debt securities not previously delivered to the trustee for cancellation. Those funds will include all principal, premium, if any, and interest, if any, to the date of the deposit or to the stated maturity, as applicable. Upon such deposit, the indenture will cease to be of further effect except as to our obligations to pay all other sums due under the indenture and to provide the officers’ certificates and opinions of counsel required under the indenture. At such time, we will be deemed to have satisfied and discharged the indenture.

In addition, at the time that we establish a series of subordinated debt securities under the indenture, we can provide that the subordinated debt securities are subject to the defeasance and discharge provisions of that indenture. Unless we specify otherwise in the applicable prospectus supplement, the debt securities offered thereby will be subject to the defeasance and discharge provisions of the applicable indenture, and we may elect either (1) to defease and be discharged from any and all obligations with respect to the subordinated debt securities of a series (except for, among other things, obligations to register the transfer or exchange of the debt securities, to replace temporary or mutilated, destroyed, lost or stolen debt securities, to maintain an office or agency with respect to the subordinated debt securities and to hold moneys for payment in trust) (“legal defeasance”) or (2) to be released from our obligations to comply with the restrictive covenants we designate when we establish the series of subordinated debt securities, and any omission to comply with such obligations will not constitute a default or an event of default with respect to such subordinated debt securities (“covenant defeasance”). Legal defeasance or covenant defeasance, as the case may be, will be conditioned upon, among other things, the irrevocable deposit by us with the trustee, in trust, of an amount in U.S. dollars, or U.S. government obligations, or both, applicable to the debt securities of that series which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal or premium, if any, and interest, if any, on the subordinated debt securities on the scheduled due dates therefor.

If we effect covenant defeasance with respect to any series of subordinated debt securities, the amount in money, or U.S. government obligations, or both, on deposit with the trustee will be sufficient, in the opinion of a nationally recognized firm of independent accountants, to pay amounts due on the subordinated debt securities of that series in accordance with the terms of the indenture and such subordinated debt securities.

We will be required to deliver to the trustee an opinion of counsel that the deposit and related defeasance will not cause the holders and beneficial owners of the debt securities of that series to recognize income, gain or loss for U.S. federal income tax purposes. If we elect legal defeasance, that opinion of counsel must be based upon a ruling from the U.S. Internal Revenue Service or a change in law to that effect.

We may exercise our legal defeasance option notwithstanding our prior exercise of our covenant defeasance option.

Governing Law

The indenture and the subordinated debt securities will be governed by, and construed in accordance with, the laws of the State of New York.

Regarding the Trustee

U.S. Bank Trust Company, National Association, is the trustee under the indenture for the subordinated debt securities. The trustee and any agents under the indenture may resign or be removed and a successor may be appointed.

The trustee under the indenture for the subordinated debt securities and its affiliates have engaged, currently engage, and may in the future engage in transactions, including commercial banking and other transactions, with us and our subsidiaries from time to time, subject to the Trust Indenture Act. An affiliate of the subordinated trustee may act as underwriter with respect to one or more series of subordinated debt securities. Consequently, if an actual or potential event of default occurs with respect to any of our subordinated debt securities, the trustee may be considered to have a conflicting interest for purposes of the Trust Indenture Act. In that case, the trustee may be required to resign and we would be required to appoint a successor trustee. If the trustee resigns following a default or for any other reason, it may be difficult to identify and appoint a qualified successor trustee.

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DESCRIPTION OF CAPITAL STOCK

General

As of the date hereof, our authorized capital stock consists of 100,000,000 shares of common stock, par value $1.00 per share, and 25,000,000 shares of preferred stock, without par value. On April 2, 2026, our shareholders approved an amendment to our restated articles of incorporation to increase the authorized shares of common stock from 100,000,000 to 300,000,000, contingent upon and effective concurrently with the effective time of the Merger. As of May 14, 2026, 76,128,118 shares of common stock and no shares of preferred stock were outstanding.

Common Stock

The holders of our common stock are entitled to one vote for each share held of record on all matters submitted to a vote of shareholders. Holders may use cumulative voting for the election of directors. Subject to preferences that may be applicable to any outstanding series of preferred stock, holders of our common stock are entitled to receive equally dividends as they may be declared by our board of directors out of funds legally available for the payment of dividends. Our revolving credit facility and other debt obligations contain restrictions on the payment of cash dividends upon a default or event of default. In the event of our liquidation or dissolution, holders of our common stock are entitled to share equally in all assets remaining after payment of liabilities and the liquidation preference of any outstanding series of preferred stock.

Holders of our common stock have no preemptive rights and have no rights to convert their common stock into any other securities. All of the outstanding shares of our common stock are, and the shares of common stock we sell in any offering will be, duly authorized, validly issued, fully paid and nonassessable.

Preferred Stock

Our board of directors has the authority, without further action by our shareholders, to issue shares of undesignated preferred stock from time to time in one or more series and to fix the related number of shares and the designations, voting powers, preferences, optional and other special rights, and restrictions or qualifications of that preferred stock. The particular terms of any series of preferred stock will be described in the prospectus supplement relating to that series of preferred stock. The rights, preferences, privileges and restrictions or qualifications of different series of preferred stock may differ from common stock and other series of preferred stock with respect to dividend rates, amounts payable on liquidation, voting rights, conversion rights, redemption provisions, sinking fund provisions and other matters. The issuance of additional series of preferred stock could:

decrease the amount of earnings and assets available for distribution to holders of common stock and other series of preferred stock;

adversely affect the rights and powers, including voting rights, of holders of common stock and other series of preferred stock; or

have the effect of delaying, deferring or preventing a change in control.

Special Meetings of Shareholders

Our amended and restated bylaws provide that special meetings of the shareholders may be called by a majority of our board of directors and shall be called by our board of directors upon the written demand of the holders of at least 10% of the votes entitled to be cast on any issue proposed to be considered at the special meeting.

Notice Requirements for Shareholder Proposals and Director Nominees

Shareholders wishing to nominate a director or to propose other action at an annual meeting must generally give advance written notice of such nomination or proposal that complies with Article I, Section 9, of our amended and restated bylaws to our secretary not less than 90 nor more than 120 days prior to the anniversary date of the immediately preceding year’s annual meeting.

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Depositary Shares

We may issue fractional shares of preferred stock rather than full shares of preferred stock. If we exercise this option, we will issue receipts for depositary shares, and each of these depositary shares will represent a fraction (to be set forth in the prospectus supplement relating to such depositary shares) of a share of a particular series of preferred stock.

The shares of any series of preferred stock underlying the depositary shares will be deposited under a deposit agreement between us and a bank or trust company selected by us. The depositary will have its principal office in the United States and a combined capital and surplus of at least $50,000,000. Subject to the terms of the deposit agreement, each owner of a depositary share will be entitled, in proportion to the applicable fraction of a share of preferred stock underlying the depositary share, to all of the rights and preferences of the preferred stock underlying that depositary share. Those rights may include dividend, voting, redemption, conversion and liquidation rights.

The depositary shares will be evidenced by depositary receipts issued under a deposit agreement. Depositary receipts will be distributed to those persons purchasing the fractional shares of preferred stock underlying the depositary shares, in accordance with the terms of the offering. We will describe the material terms of the deposit agreement, the depositary shares and the depositary receipts in the prospectus supplement relating to the depositary shares. You should also refer to the forms of the deposit agreement and depositary receipts that will be filed with the SEC in connection with the offering of the specific depositary shares.

Forum Selection Bylaw

Our amended and restated bylaws provide that the state or federal courts in Pennington County, South Dakota are the sole and exclusive forums for certain litigation.

Anti-Takeover Effects of South Dakota Law and Provisions of Our Charter and Bylaws

South Dakota law and our restated articles of incorporation and amended and restated bylaws contain certain provisions that may be characterized as anti-takeover provisions. These provisions may make it more difficult to acquire control of us or remove our management.

Control Share Acquisitions

We have elected in our restated articles of incorporation not to be subject to the control share acquisition provisions of the South Dakota Domestic Public Corporation Takeover Act, which would otherwise apply to us. These provisions provide generally that the shares of a publicly held South Dakota corporation (the “target company”) acquired by a person that exceed the thresholds of voting power described below will have the same voting rights as other shares of the same class or series only if approved by:

the affirmative vote of the majority of all outstanding shares entitled to vote, including all shares held by the acquiring person; and

the affirmative vote of the majority of all outstanding shares entitled to vote, excluding all interested shares.

Under these provisions, each time an acquiring person reaches a threshold, the acquiring person must deliver an information statement to the target company and a vote must be held as described above before the acquiring person will have any voting rights with respect to shares in excess of such threshold. The thresholds which require shareholder approval before voting powers are obtained with respect to shares acquired in excess of such thresholds are 20%, 331∕3% and 50%, respectively.

Similarly, under these provisions, shares acquired in the absence of such approval are denied voting rights and are redeemable at their then-current market value by the target company within 10 days after the acquiring person has failed to give a timely information statement to the target company or the date the shareholders voted not to grant voting rights to the acquiring person’s shares.

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Business Combinations

We are subject to the provisions of Section 47-33-17 of the South Dakota Domestic Public Corporation Takeover Act. In general, Section 47-33-17 prohibits a publicly held South Dakota corporation from engaging in a “business combination” with an “interested shareholder,” unless the business combination or the transaction in which the person became an interested shareholder is approved in a prescribed manner. A business combination with the interested shareholder must be approved by (i) our board of directors prior to the date that the person became an interested shareholder (referred to as the person’s “share acquisition date”), (ii) the affirmative vote of all of the holders of all of the outstanding voting shares, or, under some circumstances, by the affirmative vote of the holders of a majority of the outstanding voting shares not including those shares beneficially owned by the interested shareholder or any of its affiliates or associates, (iii) the affirmative vote of the holders of a majority of the outstanding voting shares not including those shares beneficially owned by the interested shareholder or any of its affiliates or associates at a meeting no earlier than four years after the interested shareholder’s share acquisition date, or (iv) the affirmative vote of the holders of a majority of the outstanding voting shares at a meeting no earlier than four years after the interested shareholder’s share acquisition date if the business combination satisfies the conditions of Section 47-33-18 of the South Dakota Domestic Public Corporation Takeover Act. Generally, an “interested shareholder” is a person who, together with affiliates and associates, beneficially owns, directly or indirectly, 10% or more of our voting stock. A “business combination” includes a merger, a transfer of 10% or more of our assets, the issuance or transfer of stock equal to 5% or more of the aggregate market value of all of our outstanding shares, the adoption of a plan of liquidation or dissolution, or other transaction resulting in a financial benefit to the interested shareholder. The provisions of Section 47-33-17 of the South Dakota Domestic Public Corporation Takeover Act may delay, defer or prevent a change in control of us without the shareholders taking further action.

Multiple Constituencies

The South Dakota Domestic Public Corporation Takeover Act further provides that our board, in determining whether to approve a merger or other change of control, may take into account both the long-term as well as short-term interests of us and our shareholders, the effect on our employees, customers, creditors and suppliers, the effect upon the community in which we operate and the effect on the economy of the state and nation. This provision may permit our board to vote against some proposals that, in the absence of this provision, it would otherwise have a fiduciary duty to approve.

Fair Price Provision

Our restated articles of incorporation require the affirmative vote of the holders of 80% or more of the outstanding shares of our voting stock to approve any “business transaction” with any “related person” or any “business transaction” in which a “related person” has an interest. However, if a majority of the continuing members of our board who are not affiliated with the related party approve the business transaction, or if the cash or fair market value of any consideration received by our shareholders pursuant to a business transaction meets certain enumerated requirements, then the 80% voting requirement will not be applicable. Generally, our restated articles of incorporation define a “business transaction” to include, among other things, a merger, asset or stock sale. Our restated articles of incorporation generally define a “related person” as any person, entity or group that, together with its affiliates and associates, beneficially owns 10% or more of our outstanding voting stock. Any amendment to our restated articles of incorporation to amend or repeal this provision similarly requires the affirmative vote of the holders of 80% or more of the outstanding shares of our voting stock. The likely effect of this provision is to delay, defer or prevent a change in control.

Board Composition

Our restated articles of incorporation and amended and restated bylaws provide for a staggered board of directors divided into three classes, with the term of office of one class expiring each year. Our restated articles of incorporation and amended and restated bylaws also provide that our directors may be removed only for cause and by the affirmative vote of the majority of the remaining members of the board of

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directors. The likely effect of our staggered board of directors and the limitation on the removal of directors is an increase in the time required for the shareholders to change the composition of our board of directors.

Authorized but Unissued Shares

The authorized but unissued shares of our common stock and preferred stock are available for future issuance without shareholder approval. These additional shares may be used for a variety of corporate purposes, including future public offerings to raise additional capital, corporate acquisitions and employee benefit plans. The existence of authorized but unissued and unreserved common stock and preferred stock could also render more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

Our board has the authority, without further shareholder approval, to issue one or more series of preferred stock that could, depending on the terms of the series, either impede or facilitate the completion of a merger, tender offer or other takeover attempt.

Shareholder Action by Written Consent Must Be Unanimous

South Dakota law provides that any action that may be taken at a meeting of shareholders may be taken without a meeting if a written consent, setting forth the action taken, is signed by all of the shareholders entitled to vote with respect to the action taken. This provision prevents holders of less than all of our common stock from unilaterally using the written consent procedure to take shareholder action.

Transfer Agent

The transfer agent and registrar for our common stock is Equiniti Trust Company, LLC. Its address is 1110 Centre Pointe Curve #101, Mendota Heights, Minnesota 55120, and its telephone number for shareholder services is (800) 468-9716.

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DESCRIPTION OF WARRANTS

Offered Warrants

We may issue warrants that are debt warrants or equity warrants. We may offer warrants separately or together with one or more additional warrants or debt or equity securities or any combination of those securities in the form of units, as described in the applicable prospectus supplement. If we issue warrants as part of a unit, the accompanying prospectus supplement will specify whether those warrants may be separated from the other securities in the unit prior to the warrants’ expiration date.

Debt Warrants

We may issue, together with debt securities or separately, warrants for the purchase of debt securities on terms to be determined at the time of sale.

Equity Warrants

We may also issue, together with equity securities or separately, warrants to purchase shares of our common or preferred stock on terms to be determined at the time of sale.

General Terms of Warrants

The applicable prospectus supplement will contain, where applicable, the following terms of and other information relating to the warrants:

the specific designation and aggregate number of, and the price at which we will issue, the warrants;

the currency with which the warrants may be purchased;

the date on which the right to exercise the warrants will begin and the date on which that right will expire or, if you may not continuously exercise the warrants throughout that period, the specific date or dates on which you may exercise the warrants;

whether the warrants will be issued in fully registered form or bearer form, in definitive or global form or in any combination of these forms, although, in any case, the form of a warrant included in a unit will correspond to the form of the unit and of any debt security included in that unit;

any applicable material United States federal income tax consequences;

the identity of the warrant agent for the warrants and of any other depositaries, execution or paying agents, transfer agents, registrars, determination agents or other agents;

the proposed listing, if any, of the warrants or any securities purchasable upon exercise of the warrants on any securities exchange;

if applicable, the minimum or maximum amount of the warrants that may be exercised at any one time;

information with respect to book-entry procedures, if any;

the terms of the securities issuable upon exercise of the warrants;

the antidilution provisions of the warrants, if any;

any redemption or call provisions;

the exercise price and procedures for exercise of the warrants;

the terms of any warrant spread and the market price of our common stock which will trigger our obligation to issue shares of our common stock in settlement of a warrant spread;

whether the warrants are to be sold separately or with other securities as part of units; and

any other terms of the warrants.

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Significant Provisions of the Warrant Agreements

We will issue the warrants under one or more warrant agreements to be entered into between us and a bank or trust company, as warrant agent, in one or more series, which will be described in the prospectus supplement for the warrants. The following summaries of significant provisions of the warrant agreements and the warrants are not intended to be comprehensive, and holders of warrants should review the detailed description of the relevant warrant agreement included in any prospectus supplement.

Modifications Without Consent of Warrantholders

We and the warrant agent may amend the terms of the warrants and the warrant certificates without the consent of the holders to:

cure any ambiguity;

cure, correct or supplement any defective or inconsistent provision; or

amend the terms in any other manner which we may deem necessary or desirable and which will not adversely affect the interests of the affected holders in any material respect.

Enforceability of Rights of Warrantholders

The warrant agents will act solely as our agents in connection with the warrant certificates and will not assume any obligation or relationship of agency or trust for or with any holders of warrant certificates or beneficial owners of warrants. Any holder of warrant certificates and any beneficial owner of warrants may, without the consent of any other person, enforce by appropriate legal action, on its own behalf, its right to exercise the warrants evidenced by the warrant certificates in the manner provided for in that series of warrants or pursuant to the applicable warrant agreement. No holder of any warrant certificate or beneficial owner of any warrants will be entitled to any of the rights of a holder of the debt securities or any other warrant property, if any, purchasable upon exercise of the warrants, including, without limitation, the right to receive the payments on those debt securities or other warrant property or to enforce any of the covenants or rights in the relevant indenture or any other similar agreement.

Registration and Transfer of Warrants

Subject to the terms of the applicable warrant agreement, warrants in registered, definitive form may be presented for exchange and for registration of transfer at the corporate trust office of the warrant agent for that series of warrants, or at any other office indicated in the prospectus supplement relating to that series of warrants, without service charge. However, the holder will be required to pay any taxes and other governmental charges as described in the warrant agreement. The transfer or exchange will be effected only if the warrant agent for the series of warrants is satisfied with the documents of title and identity of the person making the request.

New York Law to Govern

The warrants and each warrant agreement will be governed by, and construed in accordance with, the laws of the State of New York.

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DESCRIPTION OF PURCHASE CONTRACTS

We may issue purchase contracts, including contracts obligating holders to purchase from us, and us to sell to the holders, a specified principal amount of debt securities or a specified number of shares of common stock or preferred stock or any of the other securities that we may sell under this prospectus (or a range of principal amount or number of shares pursuant to a predetermined formula) at a future date or dates. The consideration payable upon settlement of the purchase contracts may be fixed at the time the purchase contracts are issued or may be determined by a specific reference to a formula set forth in the purchase contracts. The purchase contracts may be issued separately or as part of units consisting of a purchase contract and other securities or obligations issued by us or third parties, including United States treasury securities, securing the holders’ obligations to purchase the relevant securities under the purchase contracts. The purchase contracts may require us to make periodic payments to the holders of the purchase contracts or units or vice versa, and the payments may be unsecured or prefunded on some basis. The purchase contracts may require holders to secure their obligations under the purchase contracts in a specified manner and in some circumstances we may deliver newly issued prepaid purchase contracts, often referred to as “prepaid securities,” upon release to a holder of any collateral securing such holder’s obligations under the original purchase contract.

The applicable prospectus supplement will describe the terms of any purchase contracts or purchase units and, if applicable, such other securities or obligations. The description in the prospectus supplement will not necessarily be complete and will be qualified in its entirety by reference to the purchase contracts, and, if applicable, collateral arrangements, relating to the purchase contracts.

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DESCRIPTION OF UNITS

We may issue units consisting of one or more purchase contracts, warrants, debt securities, shares of preferred stock, shares of common stock or any combination of such securities. The applicable prospectus supplement will describe:

the terms of the units and of the purchase contracts, warrants, debt securities, preferred stock and/or common stock comprising the units, including whether and under what circumstances the securities comprising the units may be traded separately;

a description of the terms of any unit agreement governing the units; and

a description of the provisions for the payment, settlement, transfer or exchange of the units.

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PLAN OF DISTRIBUTION

From time to time, we may sell the securities offered by this prospectus:

through underwriters or dealers;

through agents;

directly to purchasers; or

through a combination of any of these methods of sale.

This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement. Any underwriter, dealer or agent may be deemed to be an “underwriter” within the meaning of the Securities Act of 1933.

The applicable prospectus supplement relating to the securities will set forth:

their offering terms, including the name or names of any underwriters, dealers or agents;

the purchase price of the securities and the net proceeds we may receive from the sale;

any underwriting discounts, fees, commissions and other items constituting compensation to underwriters, dealers or agents;

any initial public offering price;

any discounts, commissions or concessions allowed or reallowed or paid by underwriters or dealers to other dealers; and

any securities exchanges on which the securities may be listed.

If underwriters or dealers are used in the sale, the securities will be acquired by the underwriters or dealers for their own account and may be resold from time to time in one or more transactions:

at a fixed price or prices which may be changed;

at market prices prevailing at the time of sale;

at prices related to such prevailing market prices; or

at negotiated prices.

The securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more of such firms. Unless otherwise set forth in the applicable prospectus supplement, the obligations of underwriters or dealers to purchase the offered securities will be subject to certain conditions precedent, and the underwriters or dealers will be obligated to purchase all the offered securities if any are purchased. Any public offering price and any discounts or concessions allowed or reallowed or paid by underwriters or dealers to other dealers may be changed from time to time.

Securities may be sold directly by us or through agents designated by us from time to time. Any agent involved in the offer or sale of the securities in respect of which this prospectus is delivered will be named, and any commissions payable by us to the agent will be set forth, in the applicable prospectus supplement. Unless otherwise indicated in the applicable prospectus supplement, any such agent will be acting on a best efforts basis for the period of its appointment.

If so indicated in the applicable prospectus supplement, we will authorize underwriters, dealers or agents to solicit offers from certain specified institutions to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. Such contracts will be subject to any conditions set forth in the applicable prospectus supplement and the prospectus supplement will set forth the commission payable for solicitation of such contracts. The underwriters and other persons soliciting such contracts will have no responsibility for the validity or performance of any such contracts.

Underwriters, dealers and agents may be entitled under agreements entered into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act of 1933, or

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to contribution by us to payments which they may be required to make. Underwriters, dealers and agents may be customers of, engage in transactions with, or perform services for, us in the ordinary course of business.

Each class or series of securities will be a new issue of securities with no established trading market, other than our common stock, which is listed on the New York Stock Exchange. We may elect to list any other class or series of securities on any exchange, but are not obligated to do so. Any underwriters to whom securities are sold by us for public offering and sale may make a market in such securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice. No assurance can be given as to the liquidity of the trading market for any securities.

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LEGAL OPINIONS

The validity of the securities offered by this prospectus will be passed upon for Black Hills Corporation by Catherine M. Sabers, Associate General Counsel of Black Hills, with respect to matters governed by South Dakota law, and by Faegre Drinker Biddle & Reath LLP, special counsel to Black Hills, with respect to matters governed by New York law. Certain legal matters will be passed upon for Black Hills by Faegre Drinker Biddle & Reath LLP, and for the underwriters, dealers, or agents, if any, by their own legal counsel. As of the date of this prospectus, Ms. Sabers beneficially owns, directly or indirectly, shares of our common stock representing less than 0.1% of our outstanding common stock.

EXPERTS

Black Hills

The consolidated financial statements of Black Hills as of December 31, 2025 and 2024, and for each of the three years in the period ended December 31, 2025, incorporated in this prospectus by reference to Black Hills’ Annual Report on Form 10-K for the year ended December 31, 2025 , and the effectiveness of Black Hills’ internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports, which are incorporated herein by reference. Such consolidated financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

NorthWestern

The consolidated financial statements of NorthWestern as of December 31, 2025 and 2024, and for each of the three years in the period ended December 31, 2025, incorporated by reference in this prospectus by reference to our Form 8-K filed with the SEC on February 19, 2026 , and the effectiveness of NorthWestern’s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such consolidated financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

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WHERE YOU CAN FIND MORE INFORMATION

This prospectus constitutes a part of a registration statement on Form S-3 (together with all amendments, supplements, schedules and exhibits to the registration statement, referred to as the registration statement) that we have filed with the SEC under the Securities Act of 1933 with respect to the securities offered by this prospectus. This prospectus does not contain all the information which is in the registration statement. Certain parts of the registration statement are omitted as allowed by the rules and regulations of the SEC. We refer you to the registration statement for further information about our company and the securities offered by this prospectus. Statements contained in this prospectus concerning the provisions of documents are not necessarily complete, and each statement is qualified in its entirety by reference to the copy of the applicable document filed with the SEC.

We also file annual, quarterly and current reports, proxy statements and other information with the SEC. You can inspect and copy the registration statement and the reports and other information we file with the SEC by accessing its Internet website at www.sec.gov .

The SEC allows us to “incorporate by reference” into this prospectus the information we file with them, which means we can disclose important business and financial information about us to you by referring you to those documents. The information incorporated by reference is considered to be a part of this prospectus, except for any information that is superseded by information included directly in this prospectus and any prospectus supplement. Information that we file later with the SEC will also automatically update and supersede the information included in or incorporated by reference into this prospectus. We incorporate by reference the documents listed below that we previously filed with the SEC (SEC File No. 1-31303) and any future filings we make with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 (other than any portions of such filings that are furnished rather than filed under applicable SEC rules) until the termination of the offerings made under this prospectus:

Our Annual Report on Form 10-K for the fiscal year ended December 31, 2025 (the “2025 Annual Report”), which incorporates by reference certain portions of our definitive proxy statement for the Company’s 2026 Annual Meeting of Shareholders filed on March 18, 2026 ;

Our Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2026 ;

Our Current Reports on Form 8-K filed on February 19, 2026 , April 2, 2026 , May 1, 2026 and May 15, 2026 ; and

The description of our common stock contained in Exhibit 4.5 to our 2025 Annual Report, which updates the description of our common stock originally included in our Registration Statement on Form 8-A filed April 19, 2002 , and any other amendment or report filed for the purpose of updating such description.

These filings have not been included in or delivered with this prospectus. We will provide to each person, including any beneficial owner to whom this prospectus is delivered, a copy of any or all information that has been incorporated by reference in this prospectus but not delivered with this prospectus. You may obtain a copy of these filings, at no cost, from our Internet website www.blackhillscorp.com or by writing or telephoning us at the following address:

Black Hills Corporation

7001 Mount Rushmore Road

Rapid City, South Dakota 57702

Attention: Investor Relations

(605) 721-1700

Information on our Internet website or any other website is not incorporated by reference in this prospectus and does not constitute a part of this prospectus.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.

The following is an estimate, subject to future contingencies, of the expenses to be incurred by the Registrant in connection with the issuance and distribution of the securities being registered:

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SEC registration fee

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$ |

(*)
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Legal fees and expenses

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​ (**)

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Trustee fees and expenses

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​ (**)

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Accounting fees and expenses

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​ (**)

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Printing fees

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​ (**)

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Rating agency fees

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​ (**)

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Listing fee

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​ (**)

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Miscellaneous

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​ (**)

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Total

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$ |

​ (**)

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(*)

In accordance with Rules 456(b) and 457(r) of the Securities Act of 1933, the Registrant is deferring payment of the registration fee. Such registration fee shall be paid at the time of any particular offering of securities under the registration statement, and is therefore not currently determinable.

(**)

The calculation of these fees and expenses is dependent on the number of issuances and amount of securities offered and, therefore, cannot be estimated at this time. An estimate of the aggregate amount of these expenses will be reflected in the applicable prospectus supplement.

Item 15. Indemnification of Directors and Officers.

Section 47-1A-851 of the South Dakota Codified Laws allows a corporation to indemnify any person who was, is, or is threatened to be made a defendant or respondent to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative, arbitrative or investigative and whether formal or informal, by reason of the fact that he is or was a director or officer of the corporation, or is or was serving at the request of the corporation as a director, officer, partner, trustee, employee or agent of another corporation, partnership, joint venture, trust, employee benefit plan or other entity, against judgments, settlements, penalties, fines and reasonable expenses (including attorneys’ fees) incurred by that person in connection with such action, suit or proceeding if that person acted in good faith and in a manner that person reasonably believed to be, in the case of conduct in an official capacity, in the best interests of the corporation, and in all other cases, at least not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe such conduct was unlawful. Unless ordered by a court, the corporation may not indemnify a director (a) in respect of a proceeding by or in the right of the corporation, except for reasonable expenses incurred in connection with the proceeding if it is determined that the director has met the relevant standard of conduct in Section 47-1A-851, or (b) in connection with any proceeding with respect to conduct for which the director was adjudged liable on the basis that the director received a financial benefit to which the director was not entitled, whether or not involving action in the director’s official capacity.

Our amended and restated bylaws provide that we shall indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, including all appeals, by reason of the fact that such person is or was serving or has agreed to serve as a director or officer of us or at our request of another entity, who (1) acted in good faith, (2) reasonably believed (a) in the case of conduct in an official capacity, such conduct was in our best interests or (b) in all other cases, such conduct was at least not opposed to our best interests, and, (3) with respect to any criminal action or proceeding, the person had no reasonable cause to believe such conduct was unlawful, against liability incurred by such person in connection with the defense or settlement of such action or suit and any appeal therefrom. With respect to proceedings by or in our right to procure judgment in our favor, no indemnification

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shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to us unless and only to the extent that the court in which such action or suit was brought shall determine that, despite the adjudication of such liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity. In addition, we have entered into specific agreements with our directors and officers providing for indemnification of such persons under certain circumstances.

Our restated articles of incorporation also eliminate the personal liability of our directors for monetary damages for breach of their fiduciary duty as directors. This provision, however, does not eliminate a director’s liability (a) for any breach of the director’s duty of loyalty to us or our shareholders, (b) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c) for unlawful distributions by directors in violation of the South Dakota Codified Laws, or (d) for any transaction for which the director received an improper personal benefit.

We carry directors’ and officers’ liability insurance to insure our directors and officers against liability for certain errors and omissions and to defray costs of a suit or proceeding against an officer or director.

Item 16. Exhibits.

Exhibit

Number
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Description

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1.1*
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Form of Underwriting Agreement.
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2.1
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Agreement and Plan of Merger, dated as of August 18, 2025, by and among Black Hills Corporation, NorthWestern Energy Group, Inc. and River Merger Sub, Inc. (incorporated herein by reference to Exhibit 2.1 to the Registrant’s Form 8-K filed on August 19, 2025) .
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4.1
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Restated Articles of Incorporation of the Registrant (incorporated herein by reference to Exhibit 3 to the Registrant’s Current Report on Form 8-K filed on February 5, 2018) .

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4.2
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Amended and Restated Bylaws of the Registrant (incorporated herein by reference to Exhibit 3.2 to the Registrant’s Form 10-Q for the quarterly period ended September 30, 2025) .

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4.3
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Indenture for Senior Debt Securities dated as of May 21, 2003 between the Registrant and Computershare Trust Company, N.A. (as current successor to LaSalle Bank National Association), as Trustee (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 10-Q for the quarterly period ended June 30, 2003) .
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4.4
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First Supplemental Indenture dated as of May 21, 2003 (incorporated herein by reference to Exhibit 4.2 to the Registrant’s Form 10-Q for the quarterly period ended June 30, 2003) .

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4.5
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Second Supplemental Indenture dated as of May 14, 2009 (incorporated herein by reference to Exhibit 4 to the Registrant’s Form 8-K filed on May 14, 2009) .

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4.6
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Third Supplemental Indenture dated as of July 16, 2010 (incorporated herein by reference to Exhibit 4 to Registrant’s Form 8-K filed on July 15, 2010) .

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4.7
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Fourth Supplemental Indenture dated as of November 19, 2013 (incorporated herein by reference to Exhibit 4 to the Registrant’s Form 8-K filed on November 18, 2013) .

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4.8
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Fifth Supplemental Indenture dated as of January 13, 2016 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on January 13, 2016) .

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4.9
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Sixth Supplemental Indenture dated as of August 19, 2016 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on August 19, 2016) .

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4.10
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Seventh Supplemental Indenture dated as of August 17, 2018 (incorporated herein by reference to Exhibit 4.2 to the Registrant’s Form 8-K filed on August 17, 2018) .

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4.11
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Eighth Supplemental Indenture dated as of October 3, 2019 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on October 4, 2019) .

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4.12
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Ninth Supplemental Indenture dated as of June 17, 2020 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on June 17, 2020) .

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4.13
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Tenth Supplemental Indenture dated as of August 26, 2021 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on August 26, 2021) .

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Exhibit

Number
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Description

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4.14
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Eleventh Supplemental Indenture dated as of March 7, 2023 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on March 7, 2023).

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4.15
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Twelfth Supplemental Indenture dated as of September 15, 2023 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on September 15, 2023).

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4.16
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Thirteenth Supplemental Indenture dated as of May 16, 2024 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on May 16, 2024).

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4.17
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Fourteenth Supplemental Indenture dated as of October 2, 2025 (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on October 2, 2025).

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4.18
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Junior Subordinated Indenture dated as of November 23, 2015 between Black Hills Corporation and U.S. Bank Trust Company, National Association (as successor in interest to U.S. Bank National Association), as trustee (incorporated herein by reference to Exhibit 4.1 to the Registrant’s Form 8-K filed on November 23, 2015).
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4.19
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Form of Stock Certificate for Common Stock, Par Value $1.00 Per Share (incorporated herein by reference to Exhibit 4.2 to the Registrant’s Form 10-K for 2000).

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4.20*
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Form of Deposit Agreement (including Form of Depositary Receipt).
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4.21
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Form of Warrant Agreement (including Form of Warrant Certificate) (incorporated herein by reference to Exhibit 4.10 to the Registrant’s Post-Effective Amendment No. 2 to the Registration Statement on Form S-3 (File No. 333-101541) filed on February 4, 2003).
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4.22
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Form of Purchase Contract (including Form of Purchase Contract Certificate) (incorporated herein by reference to Exhibit 4.12 to the Registrant’s Post-Effective Amendment No. 1 to the Registration Statement on Form S-3 (File No. 333-101541) filed on January 13, 2003).
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4.23*
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Form of Unit Purchase Agreement.
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5.1
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Opinion of Catherine M. Sabers regarding the legality of the securities.

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5.2
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Opinion of Faegre Drinker Biddle & Reath LLP regarding the legality of the securities.

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23.1
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Consent of Deloitte & Touche LLP, independent registered public accounting firm for Black Hills Corporation.

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23.2
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Consent of Deloitte & Touche LLP, independent registered public accounting firm for NorthWestern Energy Group, Inc.

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23.3
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Consent of Catherine M. Sabers (included in Exhibit 5.1).

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23.4
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Consent of Faegre Drinker Biddle & Reath LLP (included in Exhibit 5.2).

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24.1
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Power of Attorney (included on the signature page to the Registration Statement).

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25.1
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Statement of Eligibility and Qualification on Form T-1 of Computershare Trust Company, N.A., Trustee (Senior Debt Securities).

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25.2
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Statement of Eligibility and Qualification on Form T-1 of U.S. Bank Trust Company, National Association, Trustee (Subordinated Debt Securities).

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107
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Filing Fee Table.

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*

To be filed by amendment or as an exhibit to a document to be incorporated by reference herein in connection with a specific offering.

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TABLE OF CONTENTS

Item 17. Undertakings.

(a) The undersigned Registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Filing Fee Table” in an exhibit to the effective registration statement;

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however , that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for purposes of determining liability under the Securities Act of 1933 to any purchaser:

(A) Each prospectus filed by the Registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(B) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5) or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii) or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however , that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or

II-4

TABLE OF CONTENTS

modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(5) That, for purposes of determining liability of the Registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned Registrant undertakes that in a primary offering of securities of the undersigned Registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrant or used or referred to by the undersigned Registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.

(b) The undersigned Registrant hereby undertakes, that, for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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TABLE OF CONTENTS ​

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Rapid City, State of South Dakota, on May 19, 2026.

BLACK HILLS CORPORATION

By:

/s/ Linden R. Evans

Linden R. Evans

President and Chief Executive Officer

POWER OF ATTORNEY

Each of the undersigned officers and directors of Black Hills Corporation, a South Dakota corporation, hereby constitutes and appoints Linden R. Evans, Kimberly Nooney and Darren Nakata, and each of them, as his or her true and lawful attorney-in-fact and agent, severally, with full power of substitution and resubstitution, in his or her name and on his or her behalf, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same with all exhibits thereto and all documents in connection therewith, with the SEC, granting unto said attorneys-in-fact and agents, and each of them full power and authority to do and perform each and every act and thing necessary or appropriate to be done with respect to this Registration Statement or any amendments or supplements hereto in and about the premises, as fully to all intents and purposes as he or she might or could do in person, thereby ratifying and confirming all that said attorneys-in-fact and agents, or their substitute or substitutes, may lawfully do or cause to be done.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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Signature

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Title

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Date

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​ |

/s/ Steven R. Mills

Steven R. Mills

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Director and Chairman
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May 19, 2026
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​ |

/s/ Linden R. Evans

Linden R. Evans

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Director, President and Chief Executive Officer (principal executive officer)
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May 19, 2026
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/s/ Kimberly F. Nooney

Kimberly F. Nooney

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Senior Vice President and Chief Financial Officer (principal financial and accounting officer)
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May 19, 2026
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/s/ Anne G. Waleski

Anne G. Waleski

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Director
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May 19, 2026
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/s/ Barry M. Granger

Barry M. Granger

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Director
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May 19, 2026
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/s/ Kathleen S. McAllister

Kathleen S. McAllister

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Director
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May 19, 2026
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II-6

TABLE OF CONTENTS

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Signature

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Title

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Date

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/s/ Robert P. Otto

Robert P. Otto

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Director
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May 19, 2026
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/s/ Scott M. Prochazka

Scott M. Prochazka

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Director
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May 19, 2026
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/s/ Tony A. Jensen

Tony A. Jensen

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Director
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May 19, 2026
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/s/ Robert F. Beard

Robert F. Beard

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Director
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May 19, 2026
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/s/ Teresa A. Taylor

Teresa A. Taylor

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Director
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May 19, 2026
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II-7

### EX-5.1 - EXHIBIT 5.1
EX-5.1
2
tm2614724d2_ex5-1.htm
EXHIBIT 5.1

Exhibit 5.1

Opinion of Catherine M. Sabers

May 19, 2026

Black Hills Corporation

7001 Mount Rushmore Road

Rapid City, South Dakota 57702

Re:       Registration
Statement on Form S-3 of Black Hills Corporation

Gentlemen:

I am Associate General Counsel
of Black Hills Corporation, a South Dakota corporation (the “ Company ”), and I have acted as counsel for the Company
in connection with the filing of a registration statement on Form S-3 (the “ Registration Statement ”), with the
Securities and Exchange Commission (the “ Commission ”) on the date hereof under the Securities Act of 1933, as amended
(the “ Act ”). The Registration Statement relates to the issuance and sale from time to time, pursuant to Rule 415
of the rules and regulations under the Act, of an indeterminate amount of securities of the Company, with such securities to include
senior debt securities (the “ Senior Debt Securities ”), subordinated debt securities (the “ Subordinated Debt
Securities ”), preferred stock (the “ Preferred Stock ”), fractional shares of Preferred Stock represented by
depositary shares (the “ Depositary Shares ”), common stock (“ Common Stock ”), warrants for the purchase
of debt or equity securities (the “ Warrants ”), purchase contracts for the purchase of debt or equity securities (the
“ Purchase Contracts ”), and units consisting any combination of such securities (“ Units ” and, together
with the Senior Debt Securities, Subordinated Debt Securities, Preferred Stock, Depositary Shares, Common Stock, Warrants, and Purchase
Contracts, the “ Securities ”). The Securities may be offered separately or together with other Securities, in separate
series, in amounts, at prices, and on terms to be set forth in the prospectus and one or more supplements to the prospectus constituting
a part of the Registration Statement, and in the Registration Statement.

Black Hills Corporation

May 19, 2026

Page 2

The
Senior Debt Securities are to be issued from time to time under the indenture dated as of May 21, 2003 between the Company and Computershare
Trust Company, N.A. (as current successor to LaSalle Bank National Association), as trustee, filed as Exhibit 4.3 to the Registration
Statement (the “ Senior Indenture ”). The Subordinated Debt Securities are to be issued from time to time under the indenture
dated as of November 23, 2015 between the Company and U.S. Bank Trust Company, National Association (as successor in interest to
U.S. Bank National Association), as trustee, filed as Exhibit 4.18 to the Registration Statement (the “ Subordinated Indenture ”).
Each series of Preferred Stock is to be issued from time to time under the Restated Articles of Incorporation, as amended, of the Company
(the “ Articles of Incorporation ”) and one or more amendments to the Articles of Incorporation or statements of designations
(each, a “ Statement of Designations ”) to be approved by the Board of Directors of the Company or a committee thereof
and filed with the Office of the Secretary of State of the State of South Dakota in accordance with Part 6 of Chapter 47-1A
of the South Dakota Business Corporation Act. The Depositary Shares are to be issued from time to time under one or more deposit agreements
in a form to be filed and incorporated into the Registration Statement, with appropriate insertions (each, a “ Deposit Agreement ”).
The Common Stock is to be issued from time to time under the Articles of Incorporation of the Company. Such Common Stock may be distributed
pursuant to (i) the Equity Distribution Sales Agreement, dated June 16, 2023, by and among the Company and Bank of Montreal,
Bank of America, N.A., MUFG Securities EMEA plc, Mizuho Markets Americas LLC, and Royal Bank of Canada (each in its capacity as purchaser
and under any Confirmation (as defined below), a “ Forward Purchase r” and together, the “ Forward Purchasers ”),
and BMO Capital Markets Corp., BofA Securities, Inc., MUFG Securities Americas Inc., Mizuho Securities USA LLC, and RBC Capital Markets,
LLC (each in its capacity as sales agent and/or principal in connection with the offering and sale of Issuance Shares, an “ Agent ”
and together, the “ Agents ”), and each in its capacity as agent for its affiliated Forward Purchaser in connection with
the offering and sale of any Forward Hedge Shares (each, a “Forward Seller” and together, the “Forward Sellers ”),
as amended (the “ Sales Agreement ”), and (ii) forward-sales transactions, to be set forth in one or more agreements
that may be entered into between the Company and a Forward Purchaser (each, a “ Confirmation ”). The Warrants are to
be issued from time to time under one or more warrant agreements substantially in the form filed as Exhibit 4.21 to the Registration
Statement, with appropriate insertions (each, a “ Warrant Agreement ”). The Purchase Contracts are to be issued from
time to time under one or more purchase contract agreements substantially in the form filed as Exhibit 4.22 to the Registration Statement,
with appropriate insertions (each, a “ Purchase Contract Agreement ”). The Units are to be issued from time to time under
one or more unit purchase agreements in a form to be filed and incorporated into the Registration Statement, with appropriate insertions
(each, a “ Unit Purchase Agreement ” and, together with the Senior Indenture, the Subordinated Indenture, the Articles
of Incorporation, each Statement of Designations, each Deposit Agreement, each Warrant Agreement, and each Purchase Contract Agreement,
the “ Governing Documents ”).

As part of the corporate action
taken and to be taken (the “ Corporate Proceedings ”) in connection with issuance of the Securities, the Board of Directors,
a committee thereof or certain authorized officers of the Company as authorized by the Board of Directors will, before the Securities
are issued under the Registration Statement, authorize the issuance and approve the terms of any Securities to be issued and sold from
time to time under the Registration Statement in accordance with the terms of the applicable Governing Documents, within the limits of
the then remaining authorized but unreserved and unissued amounts of such Securities.

I have examined or am otherwise
familiar with the Registration Statement, the Senior Indenture, the Subordinated Indenture, the form of Warrant Agreement, the form of
Purchase Contract Agreement, the Corporate Proceedings that have occurred as of the date hereof, the Articles of Incorporation and the
Amended and Restated Bylaws of the Company and such other documents, records and instruments as I have deemed necessary or appropriate
for the purposes of the opinions set forth herein.

Black Hills Corporation

May 19, 2026

Page 3

Based upon and subject to
the foregoing and the limitations, qualifications, exceptions, and assumptions set forth herein, I am of the opinion that:

1.             With
respect to Senior Debt Securities:

(a)             the
Senior Indenture constitutes a valid and binding obligation of the Company;

(b)             upon
(i) completion of all required Corporate Proceedings, and (ii) due authorization, execution, and delivery of a supplemental
indenture in respect of such Senior Debt Securities, such supplemental indenture will constitute a valid and binding obligation of the
Company; and

(c)             upon
(i) completion of the actions in paragraph 1(b) above, (ii) due execution, issuance, and delivery of such Senior Debt Securities
pursuant to the Senior Indenture and such supplemental indenture, and (iii) due authentication by the trustee and/or authenticating
agent under the Senior Indenture and such supplemental indenture of such Senior Debt Securities, such Senior Debt Securities will be valid
and binding obligations of the Company.

2.             With
respect to Subordinated Debt Securities:

(a)             the
Subordinated Indenture constitutes a valid and binding obligation of the Company;

(b)             upon
(i) completion of all required Corporate Proceedings, and (ii) due authorization, execution, and delivery of a supplemental
indenture in respect of such Subordinated Debt Securities, such supplemental indenture will constitute a valid and binding obligation
of the Company; and

(c)             upon
(i) completion of the actions in paragraph 2(b) above, (ii) due execution, issuance, and delivery of such Subordinated
Debt Securities pursuant to the Subordinated Indenture and (if applicable) supplemental indenture, and (iii) due authentication by
the trustee and/or authenticating agent under the Subordinated Indenture and such supplemental indenture of such Subordinated Debt Securities,
such Subordinated Debt Securities will be valid and binding obligations of the Company.

3.             With
respect to Preferred Stock, upon (i) completion of all required Corporate Proceedings, (ii) due authorization, execution, acknowledgement,
delivery and filing with, and recording by, as applicable, an amendment to the Articles of Incorporation or a Statement of Designations
with the Office of the Secretary of State of the State of South Dakota in respect of such Preferred Stock, and (iii) due execution,
registration of issuance, and delivery of certificates representing such Preferred Stock, such Preferred Stock will be duly and validly
issued, fully paid, and nonassessable.

Black Hills Corporation

May 19, 2026

Page 4

4.             With
respect to Depositary Shares, upon (i) completion of all required Corporate Proceedings, (ii) due authorization, execution,
and delivery of a Deposit Agreement, (iii) due authorization, execution, acknowledgement, delivery and filing with, and recording
by, as applicable, an amendment to the Articles of Incorporation or a Statement of Designations with the Office of the Secretary of State
of the State of South Dakota in respect of the Preferred Stock represented by Depositary Shares, (iv) due execution, registration
of issuance, and delivery of certificates representing such Preferred Stock to the depositary or custodian for deposit in accordance with
the terms of such Deposit Agreement, and the recordation of such Preferred Stock on the books of the Company in the name of such depositary,
custodian, or its nominee, and (v) due execution, registration of issuance, and delivery of depositary receipts evidencing such Depositary
Shares pursuant to such Deposit Agreement, such Deposit Agreement will constitute a valid and binding obligation of the Company and the
depositary receipts evidencing such Depositary Shares will be valid and binding obligations of the Company and will entitle the holders
thereof to the rights specified in such Deposit Agreement.

5.             With
respect to Common Stock distributed pursuant to the Sales Agreement or a Confirmation thereunder, such Common Shares have been duly authorized
and, when delivered to and paid for pursuant to the Sales Agreement and any Confirmation will be duly and validly issued, fully paid,
and nonassessable With respect to other Common Stock, upon (i) completion of all required Corporate Proceedings and (ii) due
execution, registration of issuance, and delivery of certificates representing such Common Stock, such Common Stock will be duly and validly
issued, fully paid, and nonassessable.

6.             With
respect to Warrants, upon (i) completion of all required Corporate Proceedings, (ii) due authorization, execution, and delivery
of a Warrant Agreement, (iii) due execution, issuance, and delivery of warrant certificates evidencing such Warrants pursuant to
such Warrant Agreement, countersigned by the warrant agent pursuant to such Warrant Agreement, and (iv) due authorization and reservation
of the Securities issuable upon conversion, exchange, or exercise of such Warrants (within the limits of the then remaining authorized
but unreserved and unissued amounts of such Securities), such Warrant Agreement will constitute a valid and binding obligation of the
Company and the warrant certificates evidencing such Warrants will be valid and binding obligations of the Company and will entitle the
holders thereof to the rights specified in such Warrant Agreement.

7.             With
respect to Purchase Contracts, upon (i) completion of all required Corporate Proceedings, (ii) due authorization, execution,
and delivery of a Purchase Contract Agreement, (iii) due execution, issuance, and delivery of certificates evidencing Purchase Contracts
pursuant to such Purchase Contract Agreement, (iv) due authentication by the purchase contract agent under such Purchase Contract
Agreement of such certificates evidencing such Purchase Contracts, and due execution of each certificate by the holder thereof or by the
purchase contract agent as attorney-in-fact for such holder, and due authorization and reservation of the Securities issuable pursuant
to such Purchase Contracts (within the limits of the then remaining authorized but unreserved and unissued amounts of such Securities),
such Purchase Contract Agreement will constitute a valid and binding obligation of the Company and the certificates evidencing such Purchase
Contracts will be the valid and binding obligations of the Company and will entitle the holders thereof to the rights specified in such
Purchase Contract Agreement.

Black Hills Corporation

May 19, 2026

Page 5

8.             With
respect to Units, upon (i) completion of all required Corporate Proceedings, (ii) if such Units will be issued pursuant to a
Unit Purchase Agreement, due authorization, execution, and delivery of such Unit Purchase Agreement, (iii) if such Units will be
evidenced by certificates, due execution, issuance, and delivery of such certificates pursuant to such Unit Purchase Agreement, and (iv) due
authorization, execution, registration of issuance, and delivery of the Securities comprising such Units (within the limits of the then
remaining authorized but unreserved and unissued amounts of such Securities), such Unit Purchase Agreement (if applicable) will constitute
a valid and binding obligation of the Company and the certificates evidencing such Units (if applicable) will be the valid and binding
obligations of the Company and will entitle the holders thereof to the rights specified in such Unit Purchase Agreement.

The foregoing opinions are
subject to the limitation that the validity, binding effect, or enforceability of the provisions of any agreement or instrument is limited
by (i) applicable bankruptcy, insolvency, reorganization, assignment for the benefit of creditors, moratorium, fraudulent conveyance,
fraudulent transfer, voidable transaction, receivership, and other laws of general application affecting the enforcement of creditors’
rights, (ii) general principles of equity, including, without limitation, concepts of materiality, reasonableness, good faith, fair
dealing, and the possible unavailability of specific performance, injunctive relief, or other equitable remedies, whether considered in
a proceeding at law or in equity, (iii) public policy considerations that may limit the rights of parties to obtain specific remedies
or enforce specific terms, and (iv) governmental authority to limit, delay or prohibit the making of payments outside the United
States.

The
foregoing opinions assume that (a) the Registration Statement and any amendments relating thereto shall have become effective under
the Act and will continue to be effective, (b) the Company will remain duly organized, validly existing, and in good standing
under the laws of the State of South Dakota, (c) at the time of the authentication and/or delivery of Securities, the Corporate Proceedings
related thereto will have been taken and will not have been modified or rescinded, there will not have occurred any change in the law
affecting the authorization, execution, delivery, validity, or enforceability of such Securities or Governing Documents, none of the particular
terms of such Securities or Governing Documents will violate any applicable law, and neither the issuance and sale of such Securities
nor the compliance by the Company with the terms of such Securities or the Governing Documents will result in a violation of any issuance
limit in the Corporate Proceedings, any agreement or instrument then binding upon the Company, or any order of any court or governmental
body having jurisdiction over the Company, (d) the consideration designated in the applicable Corporate Proceedings for any Securities
shall have been received by the Company in accordance with applicable law, (e) the Governing Documents (other than the Senior Indenture
and the Subordinated Indenture) and Securities shall have been duly authorized, executed, and delivered by all parties thereto (including
the Company), and each such party shall have complied with all legal requirements pertaining to its status as such status relates to the
right to enforce such agreements or instruments against it and shall have satisfied those legal requirements applicable to it to the extent
necessary to make such agreements or instruments enforceable against it, (f) the Senior Indenture and the Subordinated Indenture
shall have been qualified under the Trust Indenture Act of 1939, as amended, (g) the terms of the Securities will be established
in conformity with the applicable Governing Documents and so as to not violate or be void under applicable law, (h) a prospectus
supplement describing each class or series of Securities offered pursuant to the Registration Statement, to the extent required by applicable
law, will be timely filed with the Commission, and (i) any Securities issuable upon conversion, exchange, or exercise of any of the
other Securities will have been duly authorized and reserved for issuance (in each case, within the limits of the then remaining authorized
but unreserved and unissued amounts of such Securities), and duly executed and delivered and validly issued, as the case may be.

Black Hills Corporation

May 19, 2026

Page 6

I
have relied as to certain relevant facts upon certificates of public officials as to the accuracy of such factual matters, without independent
verification thereof or other investigation. I have assumed, without investigation, the following: (a) each document submitted
to me for review is accurate and complete, each such document that is an original is authentic, each such document that is a copy conforms
to an authentic original, and all signatures on each such document are genuine, and (b) the legal capacity of natural persons who
are involved on behalf of the Company to enter into and perform the referenced instrument or agreement or to carry out their role in it.

Without limiting any other
qualifications set forth herein, the opinions expressed herein are subject to the effect of generally applicable laws that may limit the
enforceability of provisions imposing increased interest rates or late payment charges upon delinquency in payment or default or providing
for liquidated damages or for premiums upon acceleration.

My opinions set forth herein
are limited to the laws of the States of South Dakota and New York and the federal laws of the United States of America, and I express
no opinion as to the effect of any other laws. Certain of the Governing Documents and Securities purport, or will purport, as applicable,
to be governed by the laws of the State of New York. To the extent the opinions set forth herein relate to the laws of the State of New
York, I have relied, with their permission, as to all matters of New York law on the opinions of Faegre Drinker Biddle &
Reath LLP dated the date hereof, which is filed herewith as Exhibit 5.2 to the Registration Statement.

This opinion is rendered as
of the date first written above and is expressly limited to the matters set forth above, and I render no opinion, whether by implication
or otherwise, as to any other matters relating to the Company or the Securities.

*           *            *

Black Hills Corporation

May 19, 2026

Page 7

I hereby consent to the filing
of this opinion as an exhibit to the Registration Statement and to being named in the Registration Statement under the caption “Legal
Opinions” with respect to the matters stated therein without implying or admitting that I am an “expert” within the
meaning of the Act, or other rules and regulations of the Commission issued thereunder with respect to any part of the Registration
Statement, including this exhibit.

|
Very truly yours, |

|
|

|
/s/ Catherine M. Sabers |

|
Catherine M. Sabers, Associate General Counsel |

### EX-5.2 - EXHIBIT 5.2
EX-5.2
3
tm2614724d2_ex5-2.htm
EXHIBIT 5.2

Exhibit 5.2

|
Faegre Drinker Biddle & Reath LLP
2200 Wells
Fargo Center
90 South Seventh Street
Minneapolis, Minnesota 55402
+1 612 766 7000 main
+1 612 766 1600 fax |

May 19, 2026

Catherine M. Sabers

Associate General Counsel

Black Hills Corporation

7001 Mount Rushmore Road

Rapid City, South Dakota 57702

Re: Registration
Statement on Form S-3 of Black Hills Corporation

Dear Ms. Sabers:

You are acting as counsel
in connection with a Registration Statement on Form S-3 (the “ Registration Statement ”) to be filed by Black Hills
Corporation, a South Dakota corporation (the “ Company ”), with the Securities and Exchange Commission (the “ Commission ”)
on the date hereof under the Securities Act of 1933, as amended (the “ Act ”). As such counsel, you are furnishing an
opinion in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Act. In connection with such opinion,
you have asked us to opine with respect to certain matters under New York law.

The Registration Statement
relates to the issuance and sale from time to time, pursuant to Rule 415 of the rules and regulations under the Act, of an indeterminate
amount of securities of the Company, with such securities to include, among others, senior debt securities (the “ Senior Debt
Securities ”), subordinated debt securities (the “ Subordinated Debt Securities ”), fractional shares of preferred
stock represented by depositary shares (the “ Depositary Shares ”), warrants for the purchase of debt or equity securities
(the “ Warrants ”), purchase contracts for the purchase of debt or equity securities (the “ Purchase Contracts ”),
and units consisting of one or more debt securities, equity securities, Warrants, Purchase Contracts, or any combination of such securities
(“ Units ” and, together with the Senior Debt Securities, Subordinated Debt Securities, Depositary Shares, Warrants,
and Purchase Contracts, the “ Securities ”). The Securities may be offered separately or together with other Securities,
in one or more series, and in amounts, at prices and on terms to be set forth in the prospectus and one or more supplements to the prospectus
constituting a part of the Registration Statement, and in the Registration Statement.

Catherine M. Sabers, Esq.

May 19, 2026

Page 2

The Senior Debt Securities
are to be issued from time to time under the indenture dated as of May 21, 2003 between the Company and Computershare Trust Company,
N.A. (as current successor to LaSalle Bank National Association), as trustee (the “ Senior Trustee ”), filed as Exhibit 4.3
to the Registration Statement (the “ Senior Indenture ”). The Subordinated Debt Securities are to be issued from time
to time under the indenture dated as of November 23, 2015 between the Company and U.S. Bank Trust Company, National Association (as
successor in interest to U.S. Bank National Association), as trustee (the “ Subordinated Trustee ”), filed as Exhibit 4.18
to the Registration Statement (the “ Subordinated Indenture ”). The Depositary Shares are to be issued from time to time
under one or more deposit agreements in a form to be filed and incorporated into the Registration Statement, with appropriate insertions
(each, a “ Deposit Agreement ”). The Warrants are to be issued from time to time under one or more warrant agreements
substantially in the form filed as Exhibit 4.21 to the Registration Statement, with appropriate insertions (each, a “ Warrant
Agreement ”). The Purchase Contracts are to be issued from time to time under one or more purchase contract agreements substantially
in the form filed as Exhibit 4.22 to the Registration Statement, with appropriate insertions (each, a “ Purchase Contract
Agreement ”). The Units are to be issued from time to time under one or more unit purchase agreements in a form to be filed and
incorporated into the Registration Statement, with appropriate insertions (each, a “ Unit Purchase Agreement ” and, together
with the Senior Indenture, the Subordinated Indenture, any supplemental indentures to the Senior Indenture or the Subordinated Indenture,
each Deposit Agreement, each Warrant Agreement, and each Purchase Contract Agreement, the “ Governing Documents ”).

As part of the corporate action
taken and to be taken (the “ Corporate Proceedings ”) in connection with issuance of the Securities, the Board of Directors
of the Company, a committee thereof or certain officers of the Company to whom such authority has been properly delegated by the Board
of Directors will be required to, before the Securities are issued under the Registration Statement, duly authorize the issuance and approve
the terms of any Securities to be issued and sold from time to time under the Registration Statement in accordance with the terms of the
applicable Governing Documents, and within the limits of the then remaining authorized but unreserved and unissued amounts of such Securities.

We have examined or are otherwise
familiar with the Registration Statement, the Senior Indenture, the Subordinated Indenture, the form of Warrant Agreement, the form of
Purchase Contract Agreement, and such other documents, records and instruments as we have deemed necessary or appropriate for the purposes
of the opinions set forth herein.

Based upon and subject to
the foregoing and the limitations, qualifications, exceptions, and assumptions set forth herein, we are of the opinion that:

1. With
respect to Senior Debt Securities:

(a) the
Senior Indenture constitutes a valid and binding obligation of the Company;

(b) upon
(i) completion of all required Corporate Proceedings, and (ii) due authorization, execution, and delivery of a supplemental
indenture by the Company and the Senior Trustee in respect of such Senior Debt Securities, such supplemental indenture will constitute
a valid and binding obligation of the Company; and

Catherine M. Sabers, Esq.

May 19, 2026

Page 3

(c) upon
(i) completion of the actions in paragraph 1(b) above, (ii) due execution, issuance, and delivery by the Company of such
Senior Debt Securities pursuant to the Senior Indenture and such supplemental indenture, (iii) due authentication by the Senior Trustee
and/or authenticating agent under the Senior Indenture and such supplemental indenture of such Senior Debt Securities, and (iv) in
the case of Senior Debt Securities issuable upon conversion, exercise or settlement of, or constituting a component of, any other Securities,
completion of all actions in respect of such other Securities referred to in the applicable paragraph hereof, such Senior Debt Securities
will be valid and binding obligations of the Company.

2. With
respect to Subordinated Debt Securities:

(a) the
Subordinated Indenture constitutes a valid and binding obligation of the Company;

(b) upon
(i) completion of all required Corporate Proceedings, and (ii) due authorization, execution, and delivery of a supplemental
indenture by the Company and the Subordinated Trustee in respect of such Subordinated Debt Securities, such supplemental indenture will
constitute a valid and binding obligation of the Company; and

(c) upon
(i) completion of the actions in paragraph 2(b) above, (ii) due execution, issuance, and delivery by the Company of such
Subordinated Debt Securities pursuant to the Subordinated Indenture and such supplemental indenture, (iii) due authentication by
the Subordinated Trustee and/or authenticating agent under the Subordinated Indenture and such supplemental indenture of such Subordinated
Debt Securities, and (iv) in the case of Subordinated Debt Securities issuable upon conversion, exercise or settlement of, or constituting
a component of, any other Securities, completion of all actions in respect of such other Securities referred to in the applicable paragraph
hereof, such Subordinated Debt Securities will be valid and binding obligations of the Company.

3. With
respect to Depositary Shares, upon (i) completion of all required Corporate Proceedings, (ii) due authorization, execution,
and delivery by the Company and the depositary or custodian for deposit of a Deposit Agreement, (iii) due authorization, execution,
acknowledgement, delivery and filing with, and recording by, as applicable, an amendment to the Articles of Incorporation of the Company
or a statement of designations with the Office of the Secretary of State of the State of South Dakota in respect of the preferred stock
of the Company represented by Depositary Shares, (iv) due authorization and issuance of such preferred stock (within the limits of
the then remaining authorized but unreserved or unissued amounts of preferred stock), (v) due execution, registration of issuance,
and delivery of certificates representing such preferred stock to the depositary or custodian for deposit in accordance with the terms
of such Deposit Agreement, and the recordation of such preferred stock on the books of the Company in the name of such depositary, custodian,
or its nominee, and (vi) due execution, registration of issuance, and delivery of depositary receipts evidencing such Depositary
Shares pursuant to such Deposit Agreement, such Deposit Agreement will constitute a valid and binding obligation of the Company and the
depositary receipts evidencing such Depositary Shares will be valid and binding obligations of the Company and will entitle the holders
thereof to the rights specified in such Deposit Agreement.

Catherine M. Sabers, Esq.

May 19, 2026

Page 4

4. With
respect to Warrants, upon (i) completion of all required Corporate Proceedings, (ii) due authorization, execution, and delivery
by the Company and the warrant agent of a Warrant Agreement, (iii) due execution, registration of issuance, and delivery of warrant
certificates evidencing such Warrants pursuant to such Warrant Agreement, countersigned by the warrant agent pursuant to such Warrant
Agreement, (iv) due authorization and reservation of the securities issuable upon conversion, exchange, or exercise of such Warrants
(within the limits of the then remaining authorized but unreserved and unissued amounts of such securities), and (v) in the case
of Warrants issuable upon conversion, exercise or settlement of, or constituting a component of, any other Securities, completion of all
actions in respect of such other Securities referred to in the applicable paragraph hereof, such Warrant Agreement will constitute a valid
and binding obligation of the Company and the warrant certificates evidencing such Warrants will be valid and binding obligations of the
Company and will entitle the holders thereof to the rights specified in such Warrant Agreement.

5. With
respect to Purchase Contracts, upon (i) completion of all required Corporate Proceedings, (ii) due authorization, execution,
and delivery by the Company and the purchase contract agent of a Purchase Contract Agreement, (iii) due execution, registration of
issuance, and delivery of certificates evidencing such Purchase Contracts pursuant to such Purchase Contract Agreement, (iv) due
authentication by the purchase contract agent under such Purchase Contract Agreement of such certificates evidencing such Purchase Contracts,
and due execution of each certificate by the holder thereof or by the purchase contract agent as attorney-in-fact for such holder, (v) due
authorization and reservation of the securities issuable pursuant to such Purchase Contracts (within the limits of the then remaining
authorized but unreserved and unissued amounts of such securities), and (vi) in the case of Purchase Contracts issuable upon conversion,
exercise or settlement of, or constituting a component of, any other Securities, completion of all actions in respect of such other Securities
referred to in the applicable paragraph hereof, such Purchase Contract Agreement will constitute a valid and binding obligation of the
Company and the certificates evidencing such Purchase Contracts will be the valid and binding obligations of the Company and will entitle
the holders thereof to the rights specified in such Purchase Contract Agreement.

6. With
respect to Units, upon (i) completion of all required Corporate Proceedings, (ii) due authorization, execution, and delivery
by the Company and the unit purchase agent of a Unit Purchase Agreement, (iii) if such Units will be evidenced by certificates, due
execution, issuance, and delivery of such certificates pursuant to such Unit Purchase Agreement, and (iv) due authorization, execution,
issuance, and delivery of the securities comprising such Units (within the limits of the then remaining authorized but unreserved and
unissued amounts of such securities), such Unit Purchase Agreement will constitute a valid and binding obligation of the Company and the
certificates evidencing such Units (if applicable) will be the valid and binding obligations of the Company and will entitle the holders
thereof to the rights specified in such Unit Purchase Agreement.

Catherine M. Sabers, Esq.

May 19, 2026

Page 5

The foregoing opinions are
subject to the limitation that the validity, binding effect, or enforceability of the provisions of any agreement or instrument is limited
by (i) applicable bankruptcy, insolvency, reorganization, assignment for the benefit of creditors, moratorium, fraudulent conveyance,
fraudulent transfer, voidable transaction, receivership, and other laws of general application affecting the enforcement of creditors’
rights, (ii) general principles of equity, including, without limitation, concepts of materiality, reasonableness, good faith, fair
dealing, and the possible unavailability of specific performance, injunctive relief, or other equitable remedies, whether considered in
a proceeding at law or in equity, (iii) public policy considerations that may limit the rights of parties to obtain specific remedies
or enforce specific terms, and (iv) governmental authority to limit, delay or prohibit the making of payments outside the United
States.

The foregoing opinions assume
that (a) the Registration Statement and any amendments relating thereto shall have become effective under the Act and will continue
to be effective, (b) the Company is and will remain duly organized, validly existing, and in good standing under the laws of the
State of South Dakota, (c) the Company has had and will have the power and authority under its organizational documents and the laws
of its jurisdiction of incorporation to authorize, execute and deliver any relevant documents and to issue and deliver any Securities,
(d) at the time of the issuance, execution, authentication acknowledgement and/or delivery of any Securities or Governing Documents,
the Corporate Proceedings related thereto will have been validly taken and will not have been modified or rescinded, there will not have
occurred any change in the law affecting the authorization, issuance, execution, authentication, acknowledgement, delivery, filing, validity,
or enforceability of such Securities or Governing Documents, none of the particular terms of such Securities or Governing Documents will
violate or be void or voidable under any applicable law, the issuance of such Securities will not result in a violation of any issuance
limit in the Corporate Proceedings, and neither the authorization, issuance, execution, authentication, acknowledgement, delivery, filing
validity, or enforceability of such Securities nor the compliance by the Company with the terms of such Securities or the Governing Documents
will result in a violation of any issuance limit in the Corporate Proceedings, any agreement or instrument then binding upon the Company,
or any order of any court or governmental body having jurisdiction over the Company, (e) the consideration designated in the applicable
Corporate Proceedings and any relevant agreements for any Securities shall have been received by the Company and such consideration shall
be legally sufficient, (f) the Governing Documents and Securities shall have been duly authorized, executed, and delivered by the
Company and each other party thereto, and each other party thereto shall have complied with all legal requirements pertaining to its status
as such status relates to the right to enforce such agreements or instruments against it and shall have satisfied those legal requirements
applicable to it to the extent necessary to make such agreements or instruments enforceable against it, (g) the terms of the Securities
will be established in conformity with the applicable Governing Documents, (h) a prospectus supplement and any other offering material
describing each class or series of Securities offered pursuant to the Registration Statement, to the extent required by applicable law,
will be timely filed with the Commission, (i) any securities issuable upon conversion, exchange, or exercise of any of the other
Securities will have been duly authorized and reserved for issuance (in each case, within the limits of the then remaining authorized
but unreserved and unissued amounts of such securities), and any issuance of such Securities will be effected in accordance with the terms
and conditions set forth in such other Securities and the Governing Documents related thereto, and (j) any legally required consents,
approvals, authorizations and other orders of the Commission and any other regulatory authorities will be obtained.

Catherine M. Sabers, Esq.

May 19, 2026

Page 6

We
have relied as to certain relevant facts upon certificates of public officials and certificates of and information provided by officers
and employees of the Company as to the accuracy of such factual matters, in each case without independent verification thereof or other
investigation. We have assumed, without investigation, the following: (a) the genuineness of signatures appearing upon certifications,
documents, and proceedings, (b) each document submitted to us for review is accurate and complete, each such document that is an
original is authentic and each such document that is a copy conforms to an authentic original, (c) the legal capacity of natural
persons who are involved on behalf of the Company to enter into and perform the referenced instrument or agreement or to carry out their
role in it, (d) the truth, accuracy and completeness of the information, representations and
warranties contained in the documents, instruments, certificates and records we have reviewed, (e) the absence of any undisclosed
modifications to the agreements and instruments reviewed by us, and (f) that New York law has or will be chosen
to govern each Governing Document and the Securities and/or certificates evidencing such Securities described in the foregoing opinions.

Without limiting any other
qualifications set forth herein, the opinions expressed herein are subject to the effect of generally applicable laws that (a) provide
for the enforcement of oral waivers or modifications where a material change of position in reliance thereon has occurred or provide that
a course of performance may operate as a waiver, (b) limit the enforcement of provisions of instruments or agreements that purport
to require waiver of the obligations of good faith, fair dealing, diligence and reasonableness, (c) limit the availability of a remedy
under certain circumstances where another remedy has been elected, (d) limit the enforceability of provisions releasing, exculpating
or exempting a party from, or requiring indemnification of or contribution to a party for, liability for its own action or inaction, to
the extent the action or inaction involves negligence, recklessness, willful misconduct or unlawful conduct or insofar as such provisions
otherwise contravene public policy, (e) may, where less than all of an instrument or agreement may be unenforceable, limit the enforceability
of the balance of the instrument or agreement to circumstances in which the unenforceable portion is not an essential part of the agreed
exchange, (f) govern and afford judicial discretion regarding the determination of damages and entitlement to attorneys’ fees
and other costs, (g) may permit a party who has materially failed to render or offer performance required by a contract to cure that
failure unless either permitting a cure would unreasonably hinder the aggrieved party from making substitute arrangements for performance
or it is important under the circumstances to the aggrieved party that performance occur by the date stated in the instrument or agreement,
(h) may require mitigation of damages, (i) may limit the enforceability of certain waivers, and (j) provide a time limitation
after which a remedy may not be enforced (i.e., statutes of limitation).

Catherine M. Sabers, Esq.

May 19, 2026

Page 7

We express no opinion as to
(i) whether a court would award a judgment in a currency other than United States dollars or as to the enforceability of any provision
specifying rates of exchange for, or requiring indemnity against loss in, converting into a specified currency the proceeds or amount
of a court judgment in another currency, (ii) any agreement to submit to the jurisdiction of any particular court or other governmental
authority (either as to personal jurisdiction or subject matter jurisdiction), any waivers of the right to jury trial, any waivers of
service of process requirements that would otherwise be applicable, any agreement that a judgment rendered by a court in one jurisdiction
may be enforced in another jurisdiction, or any provision otherwise affecting the jurisdiction or venue of courts, or (iii) any provision
waiving legal, statutory or equitable defenses or other procedural, judicial or administrative rights.

Without limiting any other
qualifications set forth herein, the opinions expressed herein are subject to the effect of generally applicable laws that may limit the
enforceability of provisions imposing increased interest rates or late payment charges upon delinquency in payment or default or providing
for liquidated damages or for premiums upon acceleration.

Our opinions set forth herein
are limited to the laws of the State of New York.

This opinion is rendered as
of the date first written above and is expressly limited to the matters set forth above, and we render no opinion, whether by implication
or otherwise, as to any other matters relating to the Company, the Securities or the Governing Documents.

We hereby consent to the filing
of this opinion as an exhibit to the Registration Statement and to being named in the Registration Statement under the caption “Legal
Opinions” with respect to the matters stated therein without implying or admitting that we are “experts” within the
meaning of the Act, or other rules and regulations of the Commission issued thereunder with respect to any part of the Registration
Statement, including this exhibit.

|
Very truly yours, |

|
|

|
/s/ Faegre Drinker Biddle & Reath LLP |

|
FAEGRE DRINKER BIDDLE & REATH LLP |

### EX-23.1 - EXHIBIT 23.1
EX-23.1
4
tm2614724d2_ex23-1.htm
EXHIBIT 23.1

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement
on Form S-3 of our reports dated February 11, 2026 relating to the financial statements of Black Hills Corporation and the effectiveness
of Black Hills Corporation's internal control over financial reporting, appearing in the Annual Report on Form 10-K of Black Hills Corporation
for the year ended December 31, 2025. We also consent to the reference to us under the heading "Experts" in such Registration
Statement.

/s/ DELOITTE & TOUCHE LLP

Minneapolis, Minnesota

May 19, 2026

### EX-FILING FEES - EX-FILING FEES
EX-FILING FEES

0001130464

2026-05-15
2026-05-15

0001130464

1

2026-05-15
2026-05-15

0001130464

2

2026-05-15
2026-05-15

0001130464

3

2026-05-15
2026-05-15

0001130464

4

2026-05-15
2026-05-15

0001130464

5

2026-05-15
2026-05-15

0001130464

6

2026-05-15
2026-05-15

0001130464

7

2026-05-15
2026-05-15

0001130464

8

2026-05-15
2026-05-15

iso4217:USD

xbrli:pure

xbrli:shares

Calculation of Filing Fee Tables

|

S-3

|

BLACK HILLS CORP /SD/

|

Table 1: Newly Registered and Carry Forward Securities
|

☐Not Applicable
|

|

|

Security Type

|

Security Class Title

|

Fee Calculation or Carry Forward Rule

|

Amount Registered

|

Proposed Maximum Offering Price Per Unit

|

Maximum Aggregate Offering Price

|

Fee Rate

|

Amount of Registration Fee

|

Carry Forward Form Type

|

Carry Forward File Number

|

Carry Forward Initial Effective Date

|

Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward

|

Newly Registered Securities
|

Fees to be Paid
|

1
|

Debt
|

Debt Securities
|

457(r)
|

|

|

|

0.0001381
|

|

|

|

|

|

Fees to be Paid
|

2
|

Equity
|

Preferred Stock
|

457(r)
|

|

|

|

0.0001381
|

|

|

|

|

|

Fees to be Paid
|

3
|

Equity
|

Depositary Shares
|

457(r)
|

|

|

|

0.0001381
|

|

|

|

|

|

Fees to be Paid
|

4
|

Equity
|

Common stock, par value $1.00
|

457(r)
|

|

|

|

0.0001381
|

|

|

|

|

|

Fees to be Paid
|

5
|

Other
|

Warrants
|

457(r)
|

|

|

|

0.0001381
|

|

|

|

|

|

Fees to be Paid
|

6
|

Other
|

Purchase Contracts
|

457(r)
|

|

|

|

0.0001381
|

|

|

|

|

|

Fees to be Paid
|

7
|

Other
|

Units
|

457(r)
|

|

|

|

0.0001381
|

|

|

|

|

|

Fees Previously Paid
|

|

|

|

|

|

|

|

|

|

|

|

|

|

Carry Forward Securities
|

Carry Forward Securities
|

8
|

Equity
|

Common stock, par value $1.00
|

415(a)(6)
|

|

|

$
183,376,179.78
|

|

|

S-3
|

333-272739
|

06/16/2023
|

$
25,324.25
|

|

|

|

Total Offering Amounts:

|

|

$
183,376,179.78

|

|

$
0.00

|

|

|

|

|

|

|

|

Total Fees Previously Paid:

|

|

|

|

$
0.00

|

|

|

|

|

|

|

|

Total Fee Offsets:

|

|

|

|

$
0.00

|

|

|

|

|

|

|

|

Net Fee Due:

|

|

|

|

$
0.00

|

|

|

|

|

Offering Note

|

1

|

Note 1a. An indeterminate aggregate initial offering price or number of securities of each identified class is being registered as may from time to time be offered at indeterminate prices. Separate consideration may or may not be received for securities that are issuable on exercise, conversion or exchange of other securities. In accordance with Rules 456(b) and 457(r) under the Securities Act of 1933, the Registrant is deferring payment of the registration fees.

Note 1b. The Debt Securities to be offered hereunder will consist of one or more series of Senior Debt Securities, Subordinated Debt Securities, Junior Subordinated Debt Securities, or any combination thereof.
|

|

2

|

See Note 1a.
|

|

3

|

See Note 1a.
|

|

4

|

See Note 1a.
|

|

5

|

See Note 1a.
|

|

6

|

See Note 1a.
|

|

7

|

See Note 1a.

Any securities registered hereunder may be sold separately or as units with other securities registered hereunder.
|

|

8

|

Pursuant to Rule 415(a)(6) under the Securities Act of 1933, this Registration Statement includes unsold securities originally registered under the Registrant's Registration Statement on Form S-3 filed with the Securities and Exchange Commission on June 16, 2023 (Registration No. 333-272739), as follows: an aggregate amount of $183,376,179.78 of common stock issuable under the registrant's at-the-market equity offering program.
|

|

Table 2: Fee Offset Claims and Sources
|

☑Not Applicable
|

|

|

Registrant or Filer Name
|

Form or Filing Type
|

File Number
|

Initial Filing Date
|

Filing Date
|

Fee Offset Claimed
|

Security Type Associated with Fee Offset Claimed
|

Security Title Associated with Fee Offset Claimed
|

Unsold Securities Associated with Fee Offset Claimed
|

Unsold Aggregate Offering Amount Associated with Fee Offset Claimed
|

Fee Paid with Fee Offset Source
|

Rules 457(b) and 0-11(a)(2)
|

Fee Offset Claims
|

|

|

|

|

|

|

|

|

|

|

|

|

Fee Offset Sources
|

|

|

|

|

|

|

|

|

|

|

|

|

Rule 457(p)
|

Fee Offset Claims
|

|

|

|

|

|

|

|

|

|

|

|

|

Fee Offset Sources
|

|

|

|

|

|

|

|

|

|

|

|

|

Table 3: Combined Prospectuses
|

☑Not Applicable
|

|

Security Type

|

Security Class Title

|

Amount of Securities Previously Registered

|

Maximum Aggregate Offering Price of Securities Previously Registered

|

Form Type

|

File Number

|

Initial Effective Date

|

|

|

|

|

|

|

|

|

FormS-3
Normalized event typeDilution Risk