NorthWestern Energy : BofA Power, Utilities & Clean Energy Conference

BofA Power, Utilities

& Clean Energy Conference

March 5, 2024

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8-K March 5, 2024

NorthWestern Energy

NorthWestern Energy Group, Inc.

dba: NorthWestern Energy

Ticker: NWE (Nasdaq) www.northwesternenergy.com

Corporate Support Office

3010 West 69th Street Sioux Falls, SD 57108 [phone]

Investor Relations Officer

Travis Meyer

605-978-2967 [e-mail]

Forward Looking Statements

During the course of this presentation, there will be forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Forward- looking statements often address our expected future business and financial performance, and often contain words such as "expects," "anticipates," "intends," "plans," "believes," "seeks," or "will."

The information in this presentation is based upon our current expectations as of the date of this document unless otherwise noted. Our actual future business and financial performance may differ materially and adversely from our expectations expressed in any forward-looking statements. We undertake no obligation to revise or publicly update our forward-looking statements or this presentation for any reason. Although our expectations and beliefs are based on reasonable assumptions, actual results may differ materially. The factors that may affect our results are listed in certain of our press releases and disclosed in the Company's 10-K and 10-Q along with other public filings with the SEC.

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Overview

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NWE - An Investment for the Long Term

Pure Electric &

Gas Utility

Solid Utility Foundation

Earnings &

Cash Flow

• 100% pure electric & natural gas utility with over 100 years of operating history
• Solid economic indicators in service territory
• Diverse electric supply portfolio ~55% hydro, wind & solar
• Residential electric & gas rates below national average
• Solid system reliability
• Low leaks per 100 miles of pipe
• Solid JD Power Overall Customer Satisfaction scores
• Approved Montana electric & natural gas and South Dakota electric rate reviews aid earnings, cash flow, and balance sheet strength
• History of consistent annual dividend growth

Recognized as one of

America's Greatest Workplaces

Attractive

Future Growth

Prospects

Financial Goals

& Metrics

Best Practices

Corporate

4 Governance

• Disciplined maintenance capital investment program focus on reliability, capacity, asset life and compliance
• Further opportunity for energy supply investment to meet significant capacity shortfalls
• Target 4%-6% EPS growth plus dividend yield to provide competitive total return
• Target dividend long-term payout ratio of 60%-70%
• Target debt to capitalization ratio of 50%-55% with liquidity of $100 million or greater

5th Best Governance Score

About NorthWestern

Montana Operations

Electric

405,500 customers

25,274 miles - transmission & distribution lines

887 MW maximum capacity owned power generation

Natural Gas

212,100 customers

7,390 miles of transmission and distribution pipeline

17.85 Bcf of gas storage capacity

Own 31.5 Bcf of proven natural gas reserves

South Dakota Operations

Electric

64,800 customers

3,675 miles - transmission & distribution lines

446 MW nameplate owned power generation

Natural Gas

49,800 customers

1,802 miles of transmission and distribution pipeline

Nebraska Operations

Natural Gas

43,100 customers

826 miles of distribution pipeline

5 Data as of 12/31/2023

The NorthWestern Value Proposition

+	~5% Dividend Yield
+
Base Capital Plan:	Incremental Opportunities:
4%-6% EPS Growth	6% + EPS Growth

	 FERC Transmission
	 Incremental generating
	capacity
	(subject to successful resource
	procurement bids)
	 Qualifying Facility and / or
	Power Purchase Agreement
	buyouts
	 Electrification supporting
	economic development
=	=
9%-11% Total Growth	11%+ Total Growth

Nearly $2.5 billion of highly executable and low-risk capital investment forecasted over the next five years.

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

See slide titled "Affirming Guidance and Growth Rate Targets" for additional information.

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A Diversified Electric and Gas Utility

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1

7

($Millions)

* Reflects settled filings in Montana and South Dakota.

NorthWestern's '80/20' rules:

Approximately 80% Electric and 80% Montana.

Over $4.8 billion of rate base investment to serve our customers

Data as reported in our 2023 10-K	(1) Utility Margin is a non-GAAP Measure. See appendix for additional disclosure.

Highly Carbon-Free Supply Portfolio

MT

SD

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Contracted coke and waste tailings as well as a majority of the contracted wind, hydro and solar are federally mandated Qualifying Facilities, as defined

NWEunder the Public Utility Regulatory Policies Act of 1978 (PURPA).

NorthWestern does not own all the renewable energy certificates (RECs) generated by contracted wind, and periodically sells its own RECs with proceeds benefiting retail customers. Accordingly, we cannot represent that 100% of carbon-free energy in the portfolio was delivered to our customers.

Based upon 2023 MWH's of owned and long-term contracted resources. Approximately 55% of our total company of owned and contracted supply is carbon-free - better than the national average of ~40% in 2022. (eia.gov table 7.2b)

Strong Utility Foundation

NWE rates as of 7/1/2023 (Electric) and December 2023 (Natural Gas) Electric source: Edison Electric Institute Typical Bills and Average Rates Report, Summer (July) 2023 Natural Gas source: US EIA - Monthly residential supply and delivery rates as of December 2023

 Solid and generally improving JD Power Overall	 Solid electric system reliability
Customer Satisfaction Scores	 Better than average natural gas leaks per mile

9 Residential electric and natural gas rates below national average

Solid Economic Indicators

Source: Company 10K's, 2020/2021 EEI Statistical Yearbook - Table 7.2 and EIA.gov

• Customer growth rates historically exceed National Averages.
• Projected population growth in our service territories in-line or better than the National Average.

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