NorthWestern Energy : Earnings Presentation Q1 2026

Published: 2026-04-29 20:16:19 ET NWE

Published on 04/29/2026 at 08:16 pm EDT

8-K Date: April 30, 2026

NorthWestern Energy

NorthWestern Energy Group, Inc.

dba: NorthWestern Energy Ticker: NWE (Nasdaq)

https://www.northwesternenergy.com

Corporate Support Office 3010 West 69th Street Sioux Falls, SD 57108 (605) 978-2900

Director - Corporate Development & Investor Relations Officer

Travis Meyer 605-978-2967

[email protected]

Recent Highlights

Reported GAAP diluted EPS of $1.03

Non-GAAP diluted EPS of $1.311

Affirming 2026 earnings guidance range of $3.68 - $3.832

Affirming long-term rate base and EPS growth rates targets of 4% - 6%3

Merger Progress

Received shareholder approval of NWE-BKH merger proposals

Constructive settlements reached with certain key intervenors in Montana,

Nebraska, and South Dakota merger dockets

Regulatory & Legislative

Constructive wildfire legislation passed in South Dakota4

Submitted a Large New Load tariff rule proposal with the MPSC

Data Centers: Signed Development Agreement with Quantica Infrastructure5

Dividend Declared: $0.67 per share payable June 30, 2026 (June 15 record date)

See slides "First Quarter 2026 Non-GAAP Earnings" and "Non-GAAP Financial Measures" that follow.

See "Strong Growth Outlook" slide that follows for major assumptions included in guidance.

Based on 2024 Adjusted Diluted Non-GAAP EPS of $3.40 and 2024 estimated rate base of $5.38 billion. See "Non-GAAP Financial

Measures" slide in appendix for additional information.

(4) See "South Dakota Wildfire Bill" slide that follows for additional information.

(5) See "Large-Load Customers" slide that follows for additional information.

Near Bozeman, Montana

(1) Utility Margin is a non-GAAP Measure. See appendix slide titled "Reconciling Gross Margin to Utility Margin" for additional disclosure.

Note: Subtotal variances may exist due to rounding.

First Quarter Net Income vs Prior Period

GAAP:

$13.4 or (17.4)%

Non-GAAP1:

$5.3 or 7.0%

First Quarter EPS vs Prior Period

GAAP:

$0.22 or (17.6)%

Non-GAAP1:

$0.09 or 7.4%

First Quarter 2026 Earnings Drivers

After-Tax EPS vs Prior Year

(1) Utility Margin is a non-GAAP measure. See appendix slide titled "Reconciling Gross Margin to Utility Margin" for additional disclosure.

The decrease in GAAP diluted EPS for the quarter vs prior year was primarily due to retail volumes and operating expenses, including merger-related costs and incremental Colstrip operating costs, partly offset by an improvement in Utility Margin primarily due to a Montana electric base rates increase.

First Quarter 2026 Utility Margin Bridge

Pre-Tax Millions vs Prior Year

$15.0 million or 4.6% increase in Utility Margin items that impact Net Income

First Quarter 2026 Non-GAAP Earnings

We estimate weather to be a $14.4 million pre-tax detriment as compared to normal, and a $16.6 million detriment as compared to first quarter 2025.

As a result of the adoption of Accounting Standard Update 2017-07 in March 2018, pension and other employee benefit expense is now disaggregated on the GAAP income statement with portions now recorded in both OG&A expense and Other (Expense) Income lines. To facilitate better understanding of trends in year-over-year comparisons, the non-GAAP adjustment above re-aggregates the expense in OG&A

- as it was historically presented prior to the ASU 2017-07 (with no impact to net income or earnings per share).

Certain merger-related costs are not tax-deductible.

Power prices in the Pacific Northwest associated with the designated power sales contracts included within our temporary PCCAM tariff waiver were insufficient to recover the operating expenses associated with the Avista Interests.

Utility Margin is a non-GAAP Measure. See appendix slide titled "Reconciling Gross Margin to Utility Margin" for additional disclosure.

Note: Subtotal variances may exist due to rounding.

Strong Growth Outlook

Affirming 2026 Non-GAAP EPS Guidance of

$3.68 - $3.83 per diluted share

Affirming long-term growth rate from 2024 base1

EPS growth of 4% to 6%

Rate base growth of 4% to 6%

Continued focus on closing the gap between earned & authorized returns

$3.2 billion 5-year capital plan including approximately $300 million

This guidance range is based upon, but not limited to, the following major assumptions:

Normal weather in our service territories;

Excludes costs related to the pending merger with Black Hills Corp.;

Approval of PCCAM waiver and power prices sufficient to recover operating expense from incremental Avista and Puget Colstrip interests;

An effective income tax rate of approximately 14%-18%; and

Diluted average shares outstanding of approximately 61.7 million.

of investment for generation development in South Dakota

Cash from operations and debt to fund base capital plan.

Equity issuances expected beginning in 2027 to fund South Dakota generation investment

Targeting FFO / Debt > 14%

(1) Based on 2024 Adjusted Diluted Non-GAAP EPS of $3.40 and 2024 estimated rate base of $5.38 billion. See "Non-GAAP Financial Measures" slide in appendix for additional information.

Highly diversified, executable, and low-risk critical capital investment plan.

Regulated Utility Five-Year Capital Plan (millions)

South Dakota Wildfire Bill

No Strict Liability:

Strict liability cannot be applied to utility operations alleged to have caused wildfire-related damages

Legal Protections for Providers:

Rebuttable presumption that a valid and current wildfire mitigation plan is reasonable

preparation for, and mitigation of, wildfire risk (burden of proof rests on plaintiffs)

4-year statute of limitations from date of initial ignition of the wildfire

Damages:

Economic: Property damages (including real property, personal property, livestock, and crops) and monetary losses (such as loss of business income)

Noneconomic: Only if death or bodily injury occurs

Punitive: Only with clear & convincing evidence of willful and wanton misconduct

SB 36 was passed by the South Dakota Legislature with broad bipartisan support in both the House (63-2) and Senate (31-3) and has been signed into law. The new law clarifies and limits wildfire-related liability risks, protecting our customers, communities, and investors.

NorthWestern plans to submit a Wildfire Mitigation Plan for SDPUC approval in the second half of 2026 and expects to update the plan every two years going forward.

Merger with Black Hills Benefits Stakeholders

Increases Scale

Position and Growth

Increases the combined company target EPS growth rate to 5-7%, supported by the doubling of each company's rate base to total of ~$11 bn with significant growth opportunities

Expands

Investment Opportunity

Leverages enhanced resources to make strategic investments that foster economic development, including addressing the growing demand for energy, including from data centers

Bringing together two complementary teams focused on reliability and exceptional customer service to deliver even greater value.

Strengthens

Balance Sheet

Strong and predictable cash flows support a customer-focused capital investment program while producing high-quality, investment-

grade credit metrics

Enhances Business Diversity

Delivering energy to more than 2.1 mm customers across multiple contiguous jurisdictions, served by a highly skilled workforce focused on safety and reliability

Strategic combination represents a highly attractive value creation opportunity for both companies.

For more information, see https://www.blackhillsnorthwesternbettertogether.com

Merger with Black Hills Timeline

Filed joint applications for approval in Montana, Nebraska, and South Dakota in Q4 2025

Nebraska hearing held on April 7, 2026; final order anticipated in Q2 2026

Settlements reached with certain key intervenors in Montana, Nebraska, and South Dakota

o Montana and South Dakota hearings are scheduled to commence on May 12th and June 22nd, respectively

Filed joint application with FERC on December 22, 2025

o Federal Power Act provides 180 days for approval with extension for good cause

Filed S-4/Joint Proxy Statement on January 30, 2026

Shareholder approvals received by both companies on April 2, 2026

Filed Hart-Scott-Rodino on March 20, 2026

The 30-day waiting period expired on April 20, 2026, satisfying a U.S. antitrust condition to closing

Data Center Process (Montana & South Dakota)

Data Center

Request

Load & Location

Supply Potential

Customer/Developer Required Timing

Queue Count: 8

High-Level

Assessment

Viability Assessment

Southwest Power Pool Screening

High Level Cost

Estimate

Queue Count: 4

Letter of Intent (LOI)

Supply Development Estimates

Development Agreement Negotiations

Queue Count: 0

Energy Service Agreement (ESA)

Regulatory Approvals (as needed)

Contract Signing

Business Development Handoff

Queue Count: 0

Construction

Project Management

Assignment

Construction Kick-Off

Supply Development

Generation Build Process

Queue Count: 0

Development Agreement

Development Deposit to Fund Studies:

Montana: System Impact Study & Facility Study

South Dakota: Southwest Power Pool Delivery Point Network Study

Queue Count: 3

Large-Load Customers

Montana

Expected to be served by overall utility portfolio, which is long capacity beginning in 2026

Filed

Diversified and highly carbon-free generating portfolio

Submitted a Large New Load tariff rule proposal with the MPSC in March 2026

South Dakota

Significant indications of interest

Any new large-load customers would require incremental capacity with infrastructure rider to provide generation cost recovery

South Dakota PUC has an established process for large-load customers with a deviated rate tariff

Development Agreement signed

Montana Large-Load Opportunities

Confidentially Announced: December 17, 2024

Company: Sabey Data Centers

Study Load: 50 MW ramping to 200 MW

Targeted Start Date: Mid-2028

Agreement Status: Letter of Intent

+ Development Agreement

Announced: December 19, 2024

Company: Atlas Power

Study Load: 75 MW ramping to 150 MW

Targeted Start Date: Late 2027

Agreement Status: Letter of Intent

+ Development Agreement

Announced: July 30, 2025

Company: Quantica Infrastructure

Study Load: 25 MW ramping to 1,100 MW

Targeted Start Date: Early 2029

Agreement Status: Letter of Intent

+ Development Agreement

Announcement:

Effective Date:

Capacity:

Acquisition Price: Status Update:

Avista

January 2023

December 31, 2025

222 MW

(111 MW each of units 3 & 4)

$0.0

Filed a temporary PCCAM tariff waiver request with the MPSC in August 2025 that would provide a near-term cost-recovery mechanism to offset a portion of the ~$18.0 million of incremental annual operating costs resulting from the transfer. The waiver was temporarily granted in January 2026.

Puget

July 2024

December 31, 2025

370 MW

(185 MW each of units 3 & 4)

$0.0

Signed contract in October 2025 to sell the dispatchable capacity and associated energy through late 2027. Revenue from the contract is expected to largely offset the ~$30 million of incremental annual operating costs resulting from the transfer. Filed with FERC for cost-based rates in October 2025, with approval received in February 2026 retroactive to January 1, 2026.

Avista and Puget Sound will remain responsible for their respective pre-closing share of environmental, asset retirement obligations, and

19 pension liabilities attributed to events or conditions existing prior to the closing of the transaction and for any future decommissioning and demolition costs associated with the existing facilities that comprise their interests

NorthWestern's acquisition of Avista and Puget's 592 MW of additional Colstrip capacity:

Avista interests advance our regulated portfolio to resource adequacy and increase facility ownership from 15% to 30%

Puget interests move ownership from 30% to 55% which provides the ability to determine strategic direction and investment decisions at the facility

Combined interests support the integration of large-load customers, delivering substantial benefits to our customers, communities, and investors

Base Capital Plan:

Approximately 4% Dividend Yield

4% to 6% EPS Growth

Incremental Opportunities:

> 6% EPS Growth

2026-2030 Capital Investment

($ Millions)

8% to 10% Total Return

Data centers & new large-load opportunities

FERC Regional Transmission

Incremental generating

capacity

(subject to successful resource procurement bids)

>10% Total Return

$3.21 billion

of highly diversified, executable and low-risk critical capital investment forecasted over the next five years.

This investment is expected to drive annualized earnings and rate base growth of approximately 4% - 6%.

Pure Electric & Gas Utility

Solid Utility Foundation

Best Practices Corporate Governance

Attractive Future Growth Prospects

Strong Earnings & Cash Flows

The pending merger with Black Hills Corporation will combine the strengths of both companies, resulting in an organization with greater scale, financial stability, and operational expertise and is designed to create a stronger, more resilient energy company focused on delivering safe, reliable, and affordable energy solutions to customers.

Rate Base & Authorized Return Summary

The revenue requirement associated with the FERC regulated portion of Montana electric transmission and ancillary services are included as revenue credits to our MPSC jurisdictional customers. Therefore, we do not separately reflect FERC authorized rate base or authorized returns.

The Montana gas revenue requirement includes a step-down which approximates annual depletion of our natural gas production assets included in rate base.

This jurisdiction was acquired in 2025 as part of the acquisition of Energy West Operations.

This table excludes insignificant jurisdictions for Montana propane delivery, Havre Pipeline Company, and Cut Bank Gas natural gas delivery.

For those items marked as "n/a," the respective settlement and/or order was not specific as to these terms.

Revenue from coal generation is not easily identifiable due to the use of bundled rates in South Dakota and other rate design and accounting considerations. However, NorthWestern is a fully regulated utility company for which rate base is the primary driver of earnings. The data to the left illustrates that NorthWestern only derives approximately 8-10% of earnings from its jointly owned coal generation rate base.

Coal Generation Rate Base as a percentage of Total Rate Base

First Quarter 2026 Financial Results

(1) Utility Margin is a non-GAAP Measure. See appendix slide titled "Reconciling Gross Margin to Utility Margin" for additional disclosure.

Note: Subtotal variances may exist due to rounding.

Utility Margin (Q1)

($ in millions)

Three Months Ended March 31,

2026

2025

Variance

Electric

$ 271.8

$ 242.7

$ 29.1

12.0%

Natural Gas

80.2

85.7

(5.5)

(6.4%)

Total Utility Margin1

$ 352.0

$ 328.4

$ 23.6

7.2%

Increase in utility margin due to the following factors:

$ 23.7 Base rates

5.5 Electric margin from the acquisition of the Puget Interests

2.2 Transmission revenue due to market conditions and rates

2.0 Non-recoverable Montana electric supply costs

(12.2) Electric retail volumes

(6.2) Natural gas retail volumes (including a $3.2 million increase due to acquisition of Energy West Operations) (3.3) Montana property tax tracker collections

(0.7) Natural gas production step down

4.0 Other

$ 15.0 Change in Utility Margin Impacting Net Income

$ 5.2 Property & other taxes recovered in revenue, offset in property & other taxes

2.6 Production tax credits, offset in income tax expense

0.8 Operating expenses recovered in revenue, offset in operating & maintenance expense

$ 8.6 Change in Utility Margin Offset Within Net Income

$ 23.6 Increase in Consolidated Utility Margin

25 Note: Subtotal variances

(1) Utility Margin is a non-GAAP Measure. See appendix slide titled "Reconciling Gross Margin to Utility Margin" for additional disclosure.

may exist due to rounding.

Operating Expenses (Q1)

($ in millions)

Three Months Ended March 31,

2026

2025

Variance

Operating & maintenance

$ 74.5

$ 56.7

$ 17.8

31.4%

Administrative & general

46.1

41.4

4.7

11.4%

Property & other taxes

50.4

43.2

7.2

16.7%

Depreciation & depletion

66.8

62.4

4.4

7.1%

Total Operating Expenses*

$ 237.8

$ 203.7

$ 34.1

16.7%

Increase in operating expenses due to the following factors:

$ 10.1 Electric generation maintenance (Including $6.4 million and $3.9 million due to the

acquisition of the Puget Interests and Avista Interests, respectively)

4.4 Depreciation expense due to plant additions and higher depreciation rates

3.5 Labor and benefits(1)

3.4 Merger-related costs, including consulting and legal fees

2.0 Property and other taxes not recoverable within trackers

1.9 Wildfire mitigation expense, partly offset by higher base revenues

0.7 Insurance expense, primarily due to increased wildfire risk premiums

0.5 Uncollectible accounts

0.2 Technology implementation and maintenance expenses

3.1 Other

$ 29.8 Change in Operating Expense Items Impacting Net Income

$ 5.2 Property and other taxes recovered in trackers, offset in revenue

0.8 Operating and maintenance expenses recovered in trackers, offset in revenue (0.7) Pension and other postretirement benefits, offset in other income(1)

(1.0) Deferred compensation, offset in other income

$ 4.3 Change in Operating Expense Items Offset Within Net Income

26 $ 34.1 Increase in Operating Expenses*

*Excluding fuel, purchased supply, and direct transmission expense.

In order to present the total change in labor and benefits, we have included the change in the non-service cost component of our pension and other postretirement benefits, which is recorded within other income on our Condensed Consolidated Statements of Income. This change is offset within this table as it does not affect our operating expenses.

Operating to Net Income (Q1)

($ in millions)

Three Months Ended March 31,

2026

2025

Variance

Operating Income

$ 114.1

$ 124.7

($10.6)

(8.5%)

Interest expense, net

(39.9)

(36.5)

3.4

9.3%

Other income, net

3.1

3.9

(0.8)

(20.5%)

Income Before Income Taxes

77.3

92.1

(14.8)

(16.1%)

Income tax expense

(13.8)

(15.2)

(1.4)

(9.2%)

Net Income

$ 63.5

$ 76.9

($13.4)

(17.4%)

27 Note: Subtotal variances may

exist due to rounding.

Tax Reconciliation (Q1)

Segment Results (Q1)

*Direct transmission expense excludes depreciation and depletion.

Utility Margin is a non-GAAP Measure. See appendix slide titled "Reconciling Gross Margin to Utility Margin" for additional disclosure.

Consists of unallocated corporate costs, including merger-related costs, and certain limited unregulated activity within the energy industry.

Electric Segment (Q1)

Utility Margin is a non-GAAP Measure. See appendix slide titled "Reconciling Gross Margin to Utility Margin" for additional disclosure.

Natural Gas Segment (Q1)

(1) Utility Margin is a non-GAAP Measure. See

appendix slide titled "Reconciling Gross Margin

Cash from Operating Activities increased by

$6.0 million. The increase in cash provided by working capital is primarily due to a decrease in our net cash outflows for energy supply costs, as shown in the table below.

Funds from Operations decreased by $15.1 million

over prior period.

No Planned Equity Issuances in 2026

Debt financing in 2026

•

Financing plans (targeting a FFO to Debt ratio > 14%) are expected to maintain our

current credit ratings and are subject to change

Amended our existing NorthWestern Energy Group $150 million term loan to extend

the maturity date from April 10, 2026 to December 31, 2026

Priced $150 million, 5.51% coupon, 10-year South Dakota First Mortgage Bonds expected to be issued on June 15, 2026

First Quarter 2026 Cash Flow

Net Under-Collected Supply Costs

($ in millions)

Beginning

(Jan. 1)

Ending

(Mar. 31)

Inflow / (Outflow)

2025

$5.9

$25.6

($19.7)

2026

$44.8

$53.4

($8.6)

2026 Decrease in Net Cash Outflows

$11.1

Balance Sheet

Debt to Total Capitalization slightly down from last quarter and inside our targeted 50% - 55% range.

Reconciling Gross Margin to Utility Margin

Note: Subtotal variances may exist due to rounding.

Management believes that Utility Margin provides a useful measure for investors and other financial statement users to analyze our financial performance in that it excludes the effect on total revenues caused by volatility in energy costs and associated regulatory mechanisms. This information is intended to enhance an investor's overall understanding of results. Under our various state regulatory mechanisms, our supply costs are generally collected from customers. In addition, Utility Margin is used by us to determine whether we are collecting the appropriate amount of energy costs from customers to allow recovery of operating costs, as well as to analyze how changes in loads (due to weather, economic or other conditions), rates and other factors impact our results of operations. Our Utility Margin measure may not be comparable to that of other companies' presentations or more useful than the GAAP information provided elsewhere in this report.

(1) Utility Margin is a non-GAAP Measure.

PCCAM Impact by Quarter

Pre-Tax $ Millions - Shareholder (Detriment) Benefit

Our electric QF liability consists of unrecoverable costs associated with contracts covered under PURPA that are part of a 2002 stipulation with the MPSC and other parties.

Risks / losses associated with these contracts are born by shareholders, not customers. Therefore, any mitigation of prior losses and / or benefits of liability reduction also accrue to shareholders.

Qualified Facility Earnings Adjustment

Remove Q4 2025 PCCAM Expense Following Suspension of 90/10 Sharing

1.7

Non-GAAP Net Income

$ 159.8

$ 160.6

$ 170.1

$ 173.8

$ 169.9

$ 182.4

$ 178.9

$ 197.3

$ 208.9

$ 220.1

Remove Q4 2025 PCCAM Expense Following Suspension of 90/10 Sharing

0.03

Non-GAAP Diluted Earnings per Share

$ 3.30

$ 3.39

$ 3.42

$ 3.35

$ 3.51

$ 3.18

$ 3.27

$ 3.40

$ 3.58

Non-GAAP Financial Measures

Pre-Tax Adjustments ($ Millions)

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

Reported GAAP Pre-Tax Income

$ 156.5

$ 176.1

$ 178.3

$ 182.2

$ 144.2

$ 190.2

$ 182.4

$ 201.6

$ 214.7

$ 187.6

Non-GAAP Adjustments to Pre-Tax Income:

Weather

15.2

(3.4)

(1.3)

(7.3)

9.8

1.1

(8.9)

4.3

10.6

14.4

Lost revenue recovery related to prior periods

(14.2)

QF liability adjustment

(17.5)

(6.9)

Electric tracker disallowance of prior period costs

12.2

9.9

Income tax adjustment

9.4

Community Renewable Energy Project Penalty

2.5

(2.3)

1.3

Impairment of Alternative Energy Storage Investment

4.2

NWE-BKH Merger Transaction Costs (not tax deductible)

9.3

Regulatory Disallowance of Certain YCGS Capital Costs

31.2

Remove Q4 2025 PCCAM Expense Following Suspension of 90/10 Sharing

2.3

Adjusted Non-GAAP Pre-Tax Income

$ 169.7

$ 172.7

$ 168.9

$ 174.9

$ 163.9

$ 184.4

$ 176.0

$ 205.9

$ 227.2

$ 246.1

Tax Adjustments to Non-GAAP Items ($ Millions)

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

GAAP Net Income

$ 164.2

$ 162.7

$ 197.0

$ 202.1

$ 155.2

$ 186.8

$ 183.0

$ 194.1

$ 224.1

$ 181.1

Non-GAAP Adjustments Taxed at 38.5% (12'-17') and 25.3% (18'-current):

Weather

9.3

(2.1)

(1.0)

(5.5)

7.3

0.8

(6.6)

3.2

7.9

10.8

Lost revenue recovery related to prior periods

(8.7)

QF liability adjustment

(13.1)

(5.2)

Electric tracker disallowance of prior period costs

7.5

7.4

Income tax adjustment

(12.5)

(12.8)

(22.8)

Community Renewable Energy Project Penalty

2.5

(2.3)

1.3

Previously claimed AMT credit

3.2

Release of Unrecognized Tax Benefit

(3.2)

(16.9)

(7.4)

Impairment of Alternative Energy Storage Investment

3.1

Natural Gas Safe Harbor Method Change

(7.0)

NWE-BKH Merger Transaction Costs (not tax deductible)

9.3

Regulatory Disallowance of Certain YCGS Capital Costs

23.3

Non-GAAP Diluted Earnings per Share

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025

Diluted Average Shares (Millions)

48.5

48.7

50.2

50.8

50.7

51.9

56.3

60.4

61.4

61.5

Reported GAAP Diluted Earnings per Share

$ 3.39

$ 3.34

$ 3.92

$ 3.98

$ 3.06

$ 3.60

$ 3.25

$ 3.22

$ 3.65

$ 2.94

Non-GAAP Adjustments:

Weather

0.19

(0.04)

(0.02)

(0.11)

0.14

0.01

(0.11)

0.05

0.13

0.18

Lost revenue recovery related to prior periods

(0.18)

QF liability adjustment

(0.26)

(0.10)

Electric tracker disallowance of prior period costs

0.16

0.15

Income tax adjustment

(0.26)

(0.25)

(0.45)

Community Renewable Energy Project Penalty

0.04

(0.04)

0.02

Previously claimed AMT credit

0.05

Release of Unrecognized Tax Benefit

(0.05)

(0.28)

(0.12)

Impairment of Alternative Energy Storage Investment

0.05

Natural Gas Safe Harbor Method Change

(0.11)

NWE-BKH Merger Transaction Costs (not tax deductible)

0.15

Regulatory Disallowance of Certain YCGS Capital Costs

0.38

Non-GAAP Financial Measures

This presentation includes financial information prepared in accordance with GAAP, as well as other financial measures, such as Utility Margin, Adjusted Non-GAAP pretax income, Adjusted Non-GAAP net income and Adjusted Non-GAAP Diluted EPS that are considered "non-GAAP financial measures." Generally, a non-GAAP financial measure is a numerical measure of a company's financial performance, financial position or cash flows that excludes (or includes) amounts that are included in (or excluded from) the most directly comparable measure calculated and presented in accordance with GAAP.

We define Utility Margin as Operating Revenues less fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion) as presented in our Consolidated Statements of Income. This measure differs from the GAAP definition of Gross Margin due to the exclusion of Operating and maintenance, Property and other taxes, and Depreciation and depletion expenses, which are presented separately in our Consolidated Statements of Income. A reconciliation of Utility Margin to Gross Margin, the most directly comparable GAAP measure, is included in this presentation.

Management also believes the presentation of Adjusted Non-GAAP pre-tax income, Adjusted Non-GAAP net income and Adjusted Non-GAAP Diluted EPS is more representative of normal earnings than GAAP pre-tax income, net income and EPS due to the exclusion (or inclusion) of certain impacts that are not reflective of ongoing earnings. The presentation of these non-GAAP measures is intended to supplement investors' understanding of our financial performance and not to replace other GAAP measures as an indicator of actual operating performance. Our measures may not be comparable to other companies' similarly titled measures.

Additional Merger Related Disclosures

No Offer or Solicitation

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

U.S. Securities Act of 1933, as amended.

Important Information and Where to Find It

Black Hills filed a registration statement on Form S-4 (No. 333-293105) with the SEC on January 30, 2026 to register the shares of Black Hill's capital stock that will be issued to NorthWestern stockholders in connection with the proposed transaction. The registration statement was declared effective on February 6, 2026, at which time Black Hills filed a final prospectus and NorthWestern filed a definitive proxy statement. Black Hills and NorthWestern commenced mailing of the joint proxy statement/prospectus to their respective stockholders on or about February 10, 2026. Investors and security holders are urged to read the registration statement and joint proxy statement/prospectus (and any other documents filed with the SEC in connection with the transaction or incorporated by reference into the joint proxy statement/prospectus) because such documents contain important information regarding the proposed transaction and related matters. Investors and security holders may obtain free copies of these documents and other documents filed with the SEC by NorthWestern or Black Hills through the website maintained by the SEC at http://www.sec.gov or by contacting the investor relations department of NorthWestern or Black Hills at [email protected] or [email protected], respectively.

Before making any investment decision, investors and security holders of NorthWestern and Black Hills are urged to read carefully the entire registration statement and joint proxy statement/prospectus, including any amendments thereto when they become available (and any other documents filed with the SEC in connection with the transaction), because they contain or will contain important information about the proposed transaction. Free copies of these documents may be obtained as described above.

Participants in Solicitation

NorthWestern, Black Hills and certain of their directors and executive officers may be deemed participants in the solicitation of proxies from the stockholders of each of NorthWestern and Black Hills in connection with the proposed transaction. Information regarding the directors and executive officers of NorthWestern and Black Hills and other persons who may be deemed participants in the solicitation of the stockholders of NorthWestern or of Black Hills in connection with the proposed transaction is included in the joint proxy statement/prospectus related to the proposed transaction, which was filed with the SEC on February 6, 2026. Information about the directors and executive officers of NorthWestern and their ownership of NorthWestern common stock can also be found in NorthWestern's filings with the SEC, including its Annual Report on Form 10-K for the fiscal year ended December 31, 2025, which was filed on February 12, 2026, under the header "Information About Our Executive Officers" and its Proxy Statement on Schedule 14A, which was filed on March 12, 2026, under the headers "Election of Directors" and "Who Owns our Stock". Information about the directors and executive officers of Black Hills and their ownership of Black Hills common stock can also be found in Black Hills' filings with the SEC, including its Annual Report on Form 10-K for the fiscal year ended December 31, 2025, which was filed on February 11, 2026, under the header "Information About Our Executive Officers," and its Proxy Statement on Schedule 14A, which was filed on March 18, 2026, under the headers "Election of Directors" and "Security Ownership of Management and Principal Shareholders," and other documents subsequently filed by Black Hills with the SEC. To the extent any such person's ownership of NorthWestern's or Black Hills' securities, respectively, has changed since the filing of such proxy statement, such changes have been or will be reflected on Forms 3, 4 or 5 filed with the SEC. Additional information regarding the interests of such participants are included in the joint proxy statement/prospectus and other relevant documents regarding the proposed transaction filed with the SEC.

Disclaimer

Northwestern Energy Group Inc. published this content on April 30, 2026, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on April 30, 2026 at 00:15 UTC.