Northwest Natural : March 2024

Investor Presentation

March 2024

Investor Information

Company Information

NW Natural Holdings 250 SW Taylor Street Portland, OR 97204 nwnaturalholdings.com

Nikki Sparley

Director, Investor Relations and

Treasury

1. [e-mail]

Forward Looking Statements

This and other presentations made by NW Natural Holdings from time to time, may contain forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995, which are subject to the safe harbors created by such Act. Forward-looking statements can be identified by words such as "anticipates," "intends," "plans," "seeks," "believes," "estimates," "expects" and similar references to future periods. Examples of forward-looking statements include, but are not limited to, statements regarding the following: plans; objectives; estimates; timing; goals; strategies; future events; projections; expectations; acquisitions and timing; completion and integration thereof; storage, pipeline and other infrastructure investments; safety; system modernization and reliability; risk profile; commodity costs and sourcing; competitive advantage; marketing success; service territory; customer service; customer and business growth; customer satisfaction ratings; weather; customer rates and timing and magnitude of potential rate changes; price advantage; customer preference; conversion potential; business risk; efficiency of business operations; regulatory recovery; business development and new business initiatives; water and wastewater industry and investments including timing, completion and integration of such investments; environmental initiatives and remediation recoveries; gas storage markets and business opportunities; gas storage development, costs, timing or returns related thereto; dispositions and timing, completion and outcomes thereof; accretion, financial positions and performance; economic and housing market trends and performance; shareholder return and value; capital expenditures; technological innovations and investments; availability and sources of liquidity; strategic goals and visions; decarbonization and the role of natural gas and the gas delivery system, including competitive renewable natural gas strategy; use of renewables such as renewable natural gas and hydrogen; low carbon pathway and Vision 2050; carbon emissions and savings; renewable natural gas projects or investments and timing related thereto; procurement of renewable natural gas for customers; workforce trends; diversity, equity and inclusion initiatives; hedge efficacy; cash flows and adequacy thereof; return on equity; capital structure; return on invested capital; revenues and earnings and timing thereof; margins; net income; operations and maintenance expense; dividends; credit ratings and profile; debt and equity issuances; the regulatory environment; effects of regulatory disallowance; timing or effects of future regulatory proceedings or future regulatory approvals; regulatory prudence reviews or deferrals; timing, outcome and effects of regulatory dockets or mechanisms or approvals, including, but not limited to, OPUC approval of the Oregon general rate case comprehensive stipulation; effects of legislation and changes in laws and regulations, including but not limited to carbon, renewable natural gas and renewable hydrogen regulations; gas supply; supply chain; effects, extent, severity and duration of COVID-19 and resulting economic disruption; the impact of efforts to mitigate risks posed by its spread, the ability of our workforce, customers or suppliers to operate or conduct business, COVID-19 expenses and financial impact and cost recovery including through regulatory deferrals, impact on capital projects, governmental actions and timing thereof, including actions to reopen the economy; and other statements that are other than statements of historical facts.

Forward-looking statements are based on our current expectations and assumptions regarding our business, the economy and other future conditions. Because forward-looking statements relate to the future, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict. Our actual results may differ materially from those contemplated by the forward-looking statements, so we caution you against relying on any of these forward-looking statements. They are neither statements of historical fact nor guarantees or assurances of future performance. Important factors that could cause actual results to differ materially from those in the forward-looking statements are discussed by reference to the factors described in Part I, Item 1A "Risk Factors," and Part II, Item 7 and Item 7A "Management's Discussion and Analysis of Financial Condition and Results of Operations," and "Quantitative and Qualitative Disclosure about Market Risk" in the Company's most recent Annual Report on Form 10-K, and in Part I, Items 2 and 3 "Management's Discussion and Analysis of Financial Condition and Results of Operations" and "Quantitative and Qualitative Disclosures About Market Risk", and Part II, Item 1A, "Risk Factors", in the Company's quarterly reports filed thereafter.

All forward-looking statements made in this presentation and all subsequent forward-looking statements, whether written or oral and whether made by or on behalf of the Company, are expressly qualified by these cautionary statements. Any forward-looking statement speaks only as of the date on which such statement is made, and we undertake no obligation to publicly update any forward-looking statement, whether as a result of new information, future developments or otherwise, except as may be required by law.

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Leadership Presenting

JUSTIN B. PALFREYMAN • President NW Natural Holdings, NW Natural, & NW Natural Water

Mr. Palfreyman is currently NW Natural Holdings' President effective May 2023. Previously, Mr. Palfreyman was NW Natural's Senior Vice President of Strategy and Business Development effective 2016. In addition, he is the President of NW Natural Water. Previously, Mr. Palfreyman was with Lazard, Freres & Co. serving as a Director in the Energy & Infrastructure Group and worked in the Infrastructure Investment Banking Group at Goldman Sachs in New York. Mr. Palfreyman has an MBA and a Master of Public Policy from The University of Chicago, and a Bachelor of Business Administration from Pacific Lutheran University.

BRODY J. WILSON • Interim CFO, Vice President, Treasurer, and Chief Accounting Officer

Mr. Wilson is currently interim Chief Financial Officer of NW Natural Holdings and Northwest Natural Gas Company ("NW Natural") effective July 28, 2023. He also currently serves as Vice President, Treasurer, and Chief Accounting Officer of NW Natural Holdings and NW Natural. Mr. Wilson has been serving as Treasurer since 2016 and was appointed NW Natural's Controller and Chief Accounting Officer in 2013. Prior to joining the Company in 2012, he was a Senior Manager in the Energy & Utility Group at PricewaterhouseCoopers LLP. Mr. Wilson holds a Bachelor of Science in Accounting from George Fox University and is a CPA in Oregon.

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Introduction

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NWN At A Glance

Gas Utility	Water & Wastewater Utilities	NW Natural Renewables
•	2.0 million people served	• Over 181,000 people served through approximately	• Investing in renewable energy and
•	800,000 connections		73,000 owned connections	the transition to a decarbonized future
• 14,000 miles of modern pipeline	• Supporting nearly 20,000 O&M service connections	• Focused on the production and supply of
• $4.5 billion in assets	• $146 million of property, plant and equipment	lower carbon fuels supporting a variety of
• Growing service territory in	•	Fast-growing service territories	sectors
	Oregon & Southwest Washington	•	Continued disciplined expansion	• Initial $50 million total investment in RNG
				production facility

Owned Utilities

Hiland

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Corporate Strategy

6	6

Conservative Strategy

Stable gas and water utility margins through progressive regulation

• Gas utility: weather, decoupling and environmental cost recovery mechanisms as well as a renewable natural gas automatic adjustment clause in Oregon
• Constructive relationships with regulators and customer groups benefit both gas and water utilities

Excellent operations and efficient cost structure

•

•

Commitment to safety, reliability, and high-quality service Continued focus on efficient business operations

Long-term growth opportunities that fit NWN's profile

• GAS UTILITY: strong cap-ex profile with attractive and growing service territory
• WATER & WASTEWATER: long-term, disciplined strategy to acquire water utilities and wastewater businesses in a highly fragmented industry with ample infrastructure investment opportunities
• COMPETITIVE RNG: potential for incremental earnings and cash flow through renewable natural gas investments, supported by long-term contracts, that could help decarbonize a variety of sectors including utility, commercial, industrial and transportation sectors

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HIGHLY REGULATED

Majority Revenues from Utilities

2023 Operating Revenues

Interstate

Storage, Water

• Other 5%

Natural

Gas Utility

95%

Favorable Customer Mix

2023 Natural Gas Utility Margin

Other1 5%

Industrial

6%

Commercial

24%

Residential

65%

1 Other is primarily margin from North Mist regulated gas storage services

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Community & Sustainability Achievements

Published ESG Report with disclosures in alignment with SASB and including components of TCFD

Environmental

• On track to meet or exceed carbon savings goal of 30% by 20351
• Saved 535,881 in 2022, taking nearly 119,000 cars off the road
• Our vision forward is being a provider of carbon neutral energy by 2050

Safety

• No cast iron or bare steel pipe in natural gas system, making our system one of the most modern and tightest in the nation
• Performed transmission pipeline inspections at about 2.5x the rate required in 2022
• By end of 2022, we had installed more than 295,000 EFVs on about 40% of service lines, compared to industry average of 27%

Governance

• Maintained well-qualified, diverse, independent and active Board with appropriate business & risk oversight
• In 2022, 10 out of 11 directors were independent
• 27% identify as culturally or racially diverse, 45% identify as women including board chair
• 100% of active NW Natural employees participated in ethics and compliance training in 2022
• Honored as one of the 2022 and 2023 World's Most Ethical
  Companies®3

Customers & Employees

• Ranked #2 in the West for residential customer service2
• In 2022, donated $1 million and 7,584 volunteer hours
• In 2022, 27% of our workforce were women, and 21% were racially or culturally diverse

Full report at nwnatural.com/about-us/the-company/sustainability

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This is an emissions savings goal equivalent to 30% of the carbon emissions from our sales customers' gas use and NW Natural company operations from 2015

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1. 2022 and 2023 J.D. Power Gas Utility Residential Customer Satisfaction Study for Large Utilities
2. "World's Most Ethical Companies" and "Ethisphere" names and marks are registered trademarks of Ethisphere LLC

LongINVESTMENT-Term InvestmentTARGETargetsS

Growth targets over the next five years include:

Consolidated Holding Company

• EPS growth of 4% - 6%1
• Strong and growing dividend2

Natural Gas Utility

• Customer growth averaging 0.8% per year
• Capital plan of $1.4 - $1.6 billion
• Rate base growth of 5% - 7%3

Water & Wastewater

Utilities

• Long-termstrategy, incremental earnings growth and diversity
• Deliberate and disciplined roll-up strategy
• Organic customer growth averaging 2.5 - 3.0% per year
• Capital plan of $120 - $140 million4 for system improvements

1. EPS growth forecasted for period 2022 - 2027 compounded annually; EPS growth rate uses 2022 EPS of $2.54 as base year
2. Future dividends are subject to Board of Director discretion and approval
3. Rate base growth forecasted for period 2023 - 2028
4. Water cap-ex plan is based on projected needs of water and wastewater utilities acquired or pending acquisition as of 12/31/23

Stable and Growing Return Proposition

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