Proxy Statement (Form DEF 14A)

250 SW TAYLOR STREET

PORTLAND, OREGON 97204

(503) 226-4211

April 17, 2026

Dear Shareholders of Northwest Natural Holding Company:

We cordially invite you to attend the 2026 Annual Meeting of Shareholders of Northwest Natural Holding Company, which will be held on Thursday, May 28, 2026, commencing at 2:00 p.m. Pacific Daylight Time, conducted via live webcast at www.virtualshareholdermeeting.com/NWN2026. We have found that this format allows shareholders to participate regardless of where they are located, and affords our shareholders the same rights and access as if the meeting were held in person, including the ability to vote shares and submit questions electronically during the meeting.

At the meeting you will be asked to consider and vote upon three proposals: (1) the election of three Class III directors for terms of three years; (2) an advisory vote to approve named executive officer compensation; and (3) the ratification of the appointment of PricewaterhouseCoopers LLP as NW Holdings' independent registered public accountants for the fiscal year 2026. Your Board of Directors unanimously recommends that you vote FOR each of Proposals 1, 2 and 3. In connection with the meeting, we enclose a notice of the meeting, a Proxy Statement, and a proxy card. You are entitled to participate in the Annual Meeting if you were a holder of record of NW Holdings common stock at the close of business on April 10, 2026, the record date set for the meeting. Please see page 2 for further instructions on attending the Annual Meeting.

Detailed information relating to NW Holdings' business activities and operating performance is contained in our 2025 Annual Report, which is also enclosed. We also invite you to review NW Holdings' annual Community and Sustainability report found at https://ir.nwnaturalholdings.com/Sustainability, which highlights all of the work NW Holdings has accomplished in these areas.

It is important that your shares are represented and voted at the meeting. Whether or not you plan to attend, please vote your shares in one of three ways: via internet, telephone or mail. Instructions regarding internet and telephone voting are included on the proxy card or Voting Instruction Form. If you elect to vote by mail, please sign, date and return the proxy card or Voting Instruction Form in the enclosed postage-paid envelope. Your proxy may be revoked at any time before it is exercised in the manner set forth in the Proxy Statement.

NOTICE OF 2026 ANNUAL MEETING OF SHAREHOLDERS

To our Shareholders:

The 2026 Annual Meeting of Shareholders of Northwest Natural Holding Company (NW Holdings or the Company) will be held on Thursday, May 28, 2026 at 2:00 p.m. Pacific Daylight Time, in a virtual meeting format only, conducted via live webcast at www.virtualshareholdermeeting.com/NWN2026 for the following purposes:

We are holding the Annual Meeting in an electronic meeting format to allow shareholders to participate regardless of their location. This format will allow you to vote your shares and submit questions electronically during the meeting in accordance with the rules of conduct for the meeting.

If you were a holder of record of NW Holdings common stock at the close of business on April 10, 2026, the record date set for the Annual Meeting, you will be entitled to vote upon all matters properly submitted to shareholder vote at the meeting.

Our Board of Directors is soliciting the proxies of all holders of NW Holdings common stock who may be unable to attend the meeting or who desire to vote by proxy before the meeting. These proxies also will instruct the fiduciary under NW Holdings' Dividend Reinvestment and Direct Stock Purchase Plan to vote any shares held for shareholders' benefit thereunder, as indicated on the proxies. In addition, the trustee of the Northwest Natural Retirement K Savings Plan (401(k) Plan) will vote any shares of NW Holdings common stock that are allocated to participants' 401(k) Plan accounts as directed by the participants. To the extent participants do not provide voting directions, the trustee will vote the undirected shares in the same proportion as the 401(k) Plan shares for which voting directions are received. A proxy card and postage-paid return envelope are included for your convenience. No postage is required if mailed within the United States. You can also vote online or by telephone using the instructions on the enclosed proxy card or Voting Instruction Form.

Your vote is very important to us. Whether or not you plan to attend the Annual Meeting, we encourage you to vote as soon as possible by promptly marking, signing, dating, and returning the enclosed proxy card or Voting Instruction Form, or by granting a proxy via the Internet or telephone in accordance with the instructions on the enclosed proxy card or Voting Instruction Form. Prompt submission of your proxy will help us avoid the additional expense of further solicitation to ensure that a quorum is present. Shareholders may vote electronically at the virtual Annual Meeting even if they have previously submitted a proxy.

April 17, 2026

Portland, Oregon

Important Notice Regarding the Availability of Proxy Materials for the 2026 Annual Meeting of Shareholders

This Proxy Statement and our 2025 Annual Report are available at www.nwnaturalholdings.com.

Table of Contents

Information Regarding 2026 Annual Meeting Of Shareholders

To Be Held May 28, 2026

PROXY STATEMENT

The Board of Directors of Northwest Natural Holding Company (NW Holdings or the Company) is soliciting the proxies of all holders of NW Holdings common stock who may be unable to attend or who desire to vote by proxy prior to the Annual Meeting of Shareholders to be held on Thursday, May 28, 2026, at 2:00 p.m. Pacific Daylight Time, in a virtual meeting format only, conducted via live webcast at www.virtualshareholdermeeting.com/NWN2026. We are holding the Annual Meeting in an electronic meeting format to allow all shareholders to participate regardless of their location. This format will allow you to vote your shares and submit questions electronically during the meeting in accordance with the rules of conduct for the meeting. The close of business on April 10, 2026 is the record date for the determination of shareholders entitled to notice of and to vote at the meeting. We request that you sign and return the enclosed proxy card or Voting Instruction Form promptly. Alternatively, you may grant your proxy by the internet or telephone.

NW Holdings' Annual Report for the fiscal year ended December 31, 2025, including audited financial statements (Annual Report), is being sent to all shareholders, together with this Proxy Statement and the accompanying proxy card or Voting Instruction Form, commencing April 17, 2026.

How to Vote by Proxy and Revoke Your Proxy

Voting by Proxy

You may vote your shares either electronically during the meeting or by duly authorized proxy. You may use the proxy card or Voting Instruction Form accompanying this Proxy Statement if you are unable to attend the meeting or you wish to have your shares voted by proxy, even if you do attend the meeting. If you are a registered shareholder, you may vote by internet, telephone, or mail, or you may vote your shares electronically during the meeting. To vote:

By internet (do not return your proxy card)

By telephone (do not return your proxy card)

By mail

2026 ANNUAL PROXY STATEMENT | 1

Revoking Your Proxy

You may revoke your proxy at any time before the proxy is exercised by: (1) delivering a written notice of revocation; (2) filing with the Corporate Secretary a subsequently dated, properly executed proxy; (3) voting after the date of the proxy by the internet or telephone; or (4) attending the meeting and voting electronically during the meeting. Your attendance at the meeting, by itself, will not constitute a revocation of a proxy. You should address any written notices of proxy revocation to: Northwest Natural Holding Company, 250 SW Taylor Street, Portland, OR 97204, Attention: Corporate Secretary.

Shares Held by Bank or Broker

If your shares are held in nominee or street name by a bank or broker, you should follow the directions on the Voting Instruction Form you receive from your bank or broker as to how to vote, change your vote, or revoke your proxy. Revocation of proxies for shares held through a broker, bank, or other nominee must be made through the appropriate nominee in accordance with its instructions.

Adjournment

If an adjournment of the meeting occurs, it will have no effect on the ability of shareholders of record as of the record date to exercise their voting rights or to revoke any previously delivered proxies.

Voting Your Securities

The 42,080,010 shares of NW Holdings common stock outstanding on April 10, 2026 were held by 3,485 shareholders residing in 50 states, the District of Columbia, and a number of foreign countries.

Each holder of NW Holdings common stock of record at the close of business on April 10, 2026 will be entitled to one vote for each share of NW Holdings common stock so held on all matters properly submitted at the meeting. Such holder will be entitled to cumulative voting for directors; that is, to cast as many votes for one candidate as shall equal the number of shares held of record multiplied by the number of directors to be elected, or to distribute such number of votes among any number of the nominees.

A majority of the shares of NW Holdings common stock outstanding at the close of business on April 10, 2026 must be represented at the meeting, either in attendance at the virtual meeting or by proxy, to constitute a quorum for the transaction of business.

It is important that your shares be represented at the meeting. Accordingly, regardless of the number of shares you hold, you are urged to submit your proxy in advance of the meeting. Alternatively, you may grant your proxy by the Internet or telephone as described above.

Attending the Annual Meeting

To allow all shareholders, regardless of location, to participate at the Annual Meeting, NW Holdings is holding the Annual Meeting in a virtual meeting format only, conducted via live webcast. In order to attend and to participate in the virtual meeting, please visit www.virtualshareholdermeeting.com/NWN2026, where you will be prompted to enter the 16-digit control number found on your proxy card or your Voting Instruction Form provided by your broker, bank, or other nominee. If you receive your Annual Meeting materials electronically and wish to attend the virtual meeting, please follow the instructions provided online for attendance. Once you have joined the virtual meeting, you may, just as you would be able to do so in person, vote your shares or submit a question electronically during the meeting by following the instructions available on the meeting website. To permit as many shareholders as possible to participate, only shareholders or their valid proxy holders may participate in the meeting. If you plan on attending the virtual meeting, we encourage you to allow ample time to log in online and recommend that you do so fifteen minutes before the meeting start time to ensure that you are logged in when the meeting begins. If you have difficulty accessing the Annual Meeting through the meeting website, a phone number will be posted on the meeting website to connect you to technical support.

2 | NORTHWEST NATURAL HOLDING COMPANY

Proposal 1-Election of Directors

NW Holdings' Restated Articles of Incorporation (Restated Articles) provide that the Board of Directors of NW Holdings (Board of Directors or Board) shall be composed of not less than nine nor more than thirteen directors, with the exact number of directors to be determined by the Board. The Board has currently fixed the number of directors at eleven. As previously disclosed, on February 25, 2026, Karen Lee notified NW Holdings that she intends to retire from the Board at the end of her current term, which expires at this year's Annual Meeting. In connection with Ms. Lee's notice and in accordance with NW Holdings' Amended and Restated Articles of Incorporation, the Board approved a resolution reducing the number of directors comprising NW Holdings' Board from eleven to ten members, effective as of the expiration of Ms. Lee's term.

The Restated Articles also provide that the Board of Directors be divided into three classes and that the number of directors in each class be as nearly equal in number as possible. Members of each class are elected to serve a three-year term with the terms of office of each class ending in successive years. The terms of the Class III directors expire at this year's Annual Meeting. Directors Anderson, Bragdon and Partain are nominees for election to the Board as Class III directors to serve until the 2029 Annual Meeting or until their successors have been duly qualified and elected. Directors Anderson and Partain were each last re-elected to the Board of Directors by the shareholders at the 2023 Annual Meeting. Mr. Bragdon was appointed to the Board of Directors effective July 12, 2025. In case any of the nominees should become unavailable for election for any reason, the persons named in the proxy will have discretionary authority to vote for a substitute. Management knows of no reason why any of the nominees would be unable to serve if elected.

Vote Required

Under Oregon law, if a quorum of shareholders is present at the Annual Meeting, the three nominees for the Class III director positions who receive the greatest number of votes cast at the meeting shall be elected directors. Abstentions and broker non-votes are counted for purposes of determining whether a quorum exists at the Annual Meeting, but are not counted and have no effect on the results of the vote for directors.

The Corporate Governance Standards adopted by the Board of Directors provide that any nominee for director in an uncontested election who receives a greater number of votes "withheld" than votes "for" is required to tender their resignation for consideration by the Governance Committee. The Governance Committee will then determine whether to recommend acceptance of, and the Board of Directors will decide whether to accept, such resignation.

INFORMATION CONCERNING NOMINEES AND DIRECTORS

Set forth below is information with respect to the nominees and continuing directors, including their recent employment or principal occupation, a summary of their specific experience, qualifications, attributes or skills that led to the conclusion they are qualified to serve as a director, the names of other public companies for which they currently serve as a director or have served as a director within the past five years, the committees on which they currently serve, and their age. Also listed is the year in which each director was elected to the NW Holdings, or Northwest Natural Gas Company (NW Natural) as the predecessor of NW Holdings, Board of Directors, as applicable.

2026 ANNUAL PROXY STATEMENT | 3

Nominees For Election to the Board of Directors

Class III Nominee Directors for Terms Expiring in 2029

Mr. Anderson served as Chief Executive Officer of NW Holdings and NW Natural until his retirement on April 1, 2025. He began serving as Chief Executive Officer of NW Natural in August 2016 and assumed the role of Chief Executive Officer of NW Holdings upon its formation in 2018. He also previously served as President of NW Natural from July 2016 to May 2023 and of NW Holdings from its inception to May 2023. Prior to that, he held positions at NW Natural, including as President and Chief Operating Officer from August 2015 to July 2016, as Executive Vice President and Chief Operating Officer from February 2014 to July 2015, as Executive Vice President of Operations and Regulation from February 2013 to February 2014, and as Senior Vice President and Chief Financial Officer from when he joined NW Natural in 2004 to February 2013. Before joining NW Natural, Mr. Anderson was Senior Vice President and Chief Financial Officer at TXU Gas. He previously held executive positions within TXU Corporation (formerly Texas Utilities) including Senior Vice President and Chief Accounting Officer, and Vice President of Investor Relations and Shareholder Services.

In addition to serving on the Boards of NW Holdings and NW Natural, Mr. Anderson serves on the Board of Directors of National Fuel Gas Company (NYSE: NFG) where he has been appointed to the Audit, Financing and Compensation Committees. Mr. Anderson previously served as Chair and a board member of the American Gas Association (AGA), where he also at various times served as Chair and/or member of numerous AGA committees, including the AGA Finance Committee, Audit Committee, Compensation Committee, Fiscal and Tax Committee, Executive Committee, and Safety, Resilience/Reliability, and Security Task Force and Clean Energy Task Force. He also served as a board trustee of the American Gas Foundation. Mr. Anderson is a past board member of the Northwest Gas Association, the Oregon Business Council, Portland Business Alliance, Portland State University Foundation, Greater Portland Inc., and a past President of The Oregon Partnership, Inc. (Lines for Life). Mr. Anderson is also a past Chair of the Associated Oregon Industries (AOI) Fiscal Policy Committee, and PSU Foundation Investment Committee, and is a past advisory board member for PSU School of Business and Oregon Department of Education Business Advisory Team. Mr. Anderson was also previously appointed by former Governor Kate Brown and served on Oregon's Global Warming Commission. Mr. Anderson holds a BBA in Accounting from Texas Tech University and is a Certified Public Accountant (ret.) and Chartered Global Management Accountant.

Mr. Anderson's over 20 years with NW Natural, including nine years as Chief Executive Officer, and his over 35 years' experience in the electric, gas, and water/wastewater industries, and his extensive involvement with the AGA and Northwest Gas Association enable him to bring to the Board a comprehensive understanding of the Company's business operations, as well as the energy industry generally. Mr. Anderson's service on local business, educational, charitable and public service boards provides an important connection between NW Holdings and the communities it serves. Additionally, his extensive experience in finance and operations provides important perspectives with respect to the Company's strategy, risk oversight, change management, business, operations, and financial positioning. Mr. Anderson's combined professional skills and insights from his former position as Chief Executive Officer, as well as his other roles and experiences, strengthen the Board's collective knowledge, capabilities and experience.

4 | NORTHWEST NATURAL HOLDING COMPANY

Mr. Bragdon was appointed President of Columbia Sportswear Company (Nasdaq: COLM) in November 2025. Prior to his appointment, Mr. Bragdon served as Executive Vice President, Chief Administrative Officer and General Counsel of Columbia since 2015. He joined Columbia in 1999 and served as Senior Counsel and Director of Intellectual Property until January 2003. From 2003 to 2004, Mr. Bragdon served as Chief of Staff in the Oregon Governor's office. Mr. Bragdon returned to Columbia in 2004 as Vice President, General Counsel and Secretary and was named Senior Vice President of Legal and Corporate Affairs, General Counsel and Secretary in 2010 and Executive Vice President, Chief Administrative Officer, General Counsel and Secretary in 2015. In 2017, he assumed oversight of Columbia's international distributor business. Prior to Columbia, Mr. Bragdon served as an attorney in the corporate securities and finance group at Stoel Rives LLP, and Special Assistant Attorney General for the Oregon Department of Justice. Mr. Bragdon also sits on the Board of NW Natural. He currently serves as Chair of the Board of the Oregon Community Foundation, a board member of the Portland Branch of the Federal Reserve Bank of San Francisco, and sits on the Board of Trustees of Reed College. He also serves on the Board of the World Federation of the Sporting Goods Industry. He received a Juris Doctorate from Stanford Law School, a Master of Studies in Law from Yale Law School, and a Bachelor of Arts from Amherst College.

Mr. Bragdon brings to the NW Holdings Board deep executive, legal, and governance experience developed over more than two decades at Columbia Sportswear Company, where he currently serves as President. He has overseen legal matters, corporate governance, public company compliance, enterprise risk management, mergers and acquisitions, and strategic business development, equipping him to provide valuable guidance on complex legal and strategic matters. In addition, his leadership of public policy, government relations, and stakeholder engagement at Columbia, together with his prior service as Chief of Staff to the Governor of Oregon, enables him to contribute meaningful insights on legislative, regulatory, and public affairs matters. His combined strategic, policy, and legal experience strengthens the Board's collective knowledge, capabilities and experience.

Mr. Partain is the former President and Co-Chief Investment Officer of Duff & Phelps Investment Management Co., a position he held from 2005 until December 2020. Previously, Mr. Partain served as Executive Vice President of Duff & Phelps. Earlier, he was with Duff & Phelps Investment Research Co., where he served as the Director of Utility Research, Director of Equity Research, and Director of Fixed Income Research. Mr. Partain also previously served as President and Chief Executive Officer of DNP Select Income Fund Inc. (DNP), from 2001 to March 2021, and was Chief Investment Officer of DNP from 1998 to 2017. He also served as President and Chief Executive Officer of Duff & Phelps Utility and Corporate Bond Trust Inc. (DUC) and DTF Tax-Free Income Inc. (renamed DTF Tax-Free Income 2028 Term Fund Inc. in 2022) (DTF) from 2004 to March 2021 and President and Chief Executive Officer of Duff & Phelps Utility and Infrastructure Fund Inc. (DPG) from 2011 to March 2021. DNP, DTF and DPG (and formerly DUC until its merger with DNP in 2021) are part of a single "fund complex" of registered investment companies under SEC rules that share a common board of directors (the Duff & Phelps Fund Complex). Mr. Partain previously served as a director of the Duff & Phelps Fund Complex until March 2022, having served as a director of DNP and DTF since 2007 and DPG since 2011 (he also served as a director of DUC from 2007 to 2021). Prior to joining Duff & Phelps, Mr. Partain held financial and regulatory positions with Gulf States Utilities Company. Mr. Partain serves on the Board of NW Natural and has served on the Board of Directors of Otter Tail Corporation (Nasdaq: OTTR), an electricity and energy services company, since 1993 and as its Chair since 2011. Mr. Partain is

2026 ANNUAL PROXY STATEMENT | 5

a past National Association of Corporate Directors (NACD) Board Leadership Fellow. He earned a BS and MBA from Sam Houston State University. Mr. Partain is a Chartered Financial Analyst (CFA) and a member of the CFA Society of Chicago.

Mr. Partain brings to the NW Holdings Board significant board oversight and executive leadership, financial, strategic and governance expertise as a result of his many years of experience at Duff & Phelps. Mr. Partain's service as Chair of the Board of Otter Tail Corporation enables him to provide important insight and advice to the Board on a wide range of matters related to the utility and energy industry, including in areas of renewable energy, decarbonization and sustainability. He additionally brings to the Board extensive knowledge of the utility industry gained from over 30 years of providing utility investment research and management services to institutional clients of Duff & Phelps and from his roles with Gulf States Utilities Company, and he is well positioned to advise management on matters of business strategy, growth and development, finance and capital markets, human capital management, and executive compensation. Mr. Partain's deep industry knowledge, as well as his financial, governance and executive experience, strengthen the Board's collective knowledge, capabilities and experience.

Members of the Board of Directors Continuing in Office

Class I Directors With Terms Expiring in 2027

In 2008, Ms. Enand founded Zapproved, Inc., a cloud-based software provider for corporate legal departments, where she served as Chief Executive Officer until February 2023 following the acquisition of Zapproved by Exterro. Prior to founding Zapproved, she was the Director of Business Development and Marketing at Avnera Corporation, a fabless semiconductor manufacturer. Ms. Enand has also held sales and marketing positions at IBM and was a program manager in the compiler and architecture group at Intel. Ms. Enand also serves as a board member of NW Natural. Additionally, she currently serves as Chair of the Board of Curity and sits on the boards of Nextpoint, Inc., the Oregon Community Foundation, where she chairs the Investment and Audit Committees, and Project Wayfinder. She is also an Oregon Business Council Fellow. Ms. Enand has previously served as Chair of Auth0 and Technology Association of Oregon, and as a member of Oregon Growth Board, Oregon Innovation Council, and Oregon Investment Council. She received the 2018 Sam Blackman Award for Civic Engagement, the 2016 Portland Business Journal Entrepreneur of the Year Award and the 2010 Portland Business Journal Orchid Award for achievement for women in business. Ms. Enand earned a bachelor's degree in computer engineering from Carnegie Mellon University and a Masters of Business Administration from the University of Portland.

Ms. Enand brings to the NW Holdings Board entrepreneurial and executive expertise from her more than a decade of experience founding and leading Zapproved, as well as substantial technological background from years of working in the technology industry. Ms. Enand's current and previous professional and management experiences in technology, business development, sales, and marketing allow Ms. Enand to provide oversight of, and contribute important insights on, the Company's strategy and strategic direction, business development, growth and expansion activities, mergers and acquisitions, business diversification, change management, cyber and information security, finance, compliance, human capital management, marketing and sales, and customer experience and support, which strengthens the Board's collective knowledge, capabilities and experience.

6 | NORTHWEST NATURAL HOLDING COMPANY

Mr. Palfreyman is President and Chief Executive Officer of NW Holdings and Chief Executive Officer of NW Natural, effective as of April 1, 2025. From May 2023 to March 2025, Mr. Palfreyman served as President of NW Holdings and NW Natural. He previously served as Senior Vice President, Strategy and Business Development of NW Natural from February 2023 to May 2023, and from 2016 to 2023, he was Vice President, Strategy and Business Development of NW Natural. Before joining NW Natural, he was with Lazard, Freres & Co., a global financial advisory and asset management firm, serving as a Director in Lazard's Power, Energy & Infrastructure Group from 2009 to 2016. In that position, he provided strategic and financial advice to corporations, institutional investors, private equity funds and government clients. Prior to Lazard, Mr. Palfreyman was an associate in the Infrastructure Investment Banking Group at Goldman Sachs in New York. He has also held various positions in finance, strategy and business development at both Apex Learning and Accenture in Seattle, Washington. In addition to serving on the Boards of NW Holdings and NW Natural, Mr. Palfreyman is a member of the Board of Directors for various NW Holdings' subsidiaries, including NW Natural Renewables Holdings, LLC, SiEnergy Operating, LLC (SiEnergy) and NW Natural Water Company, LLC (NW Natural Water) and their respective subsidiaries.

Mr. Palfreyman currently serves as a board member of the American Gas Association (AGA), a board trustee of the American Gas Foundation, a board member of the Oregon Business Council and a board member of CASA for Children of Multnomah, Washington, Columbia and Tillamook Counties, having been the past President. Mr. Palfreyman graduated from Pacific Lutheran University with a Bachelor of Business Administration. He also holds a Master of Business Administration from The University of Chicago Booth School of Business and a Master of Public Policy from The University of Chicago Irving B. Harris School of Public Policy.

Mr. Palfreyman serves a key leadership role on the Boards of NW Holdings and NW Natural and provides the Boards with in-depth knowledge of each area of NW Holdings' and NW Natural's business, its finances and operations, the energy and utilities industries generally, and the Company's strategy, challenges and opportunities. He acts as the principal intermediary between management and the non-management directors of our Board. Mr. Palfreyman has served in several key officer roles at NW Natural over the past decade, which enables him to provide important insights on the Company's business, operations and strategy as well as matters relating to the energy and utilities industries generally, including gas, water and renewables. Additionally, his extensive professional experience enables him to provide valuable guidance on matters related to strategy, business development, risk oversight, mergers and acquisitions, growth, and operations. Mr. Palfreyman's insights from his position as Chief Executive Officer as well as his other roles and experiences, strengthen the Board's collective knowledge, capabilities and experience.

Since March 2015, Ms. Wasson has been the Chief Executive Officer of Sand Creek Advisors LLC, which provides business consulting to chief executive officers of public and private companies. Previously, Ms. Wasson was an Executive Vice President of Commercial Banking at U.S. Bank, N.A., and served as President of U.S. Bank's Oregon and Southwest Washington operations from 2005 to 2015. She also led the U.S. Bank, N.A. Advisory Board in Portland, Oregon. Ms. Wasson is a 33-year veteran of the banking industry. Prior to joining U.S. Bank in 1989, she held various commercial lending positions with the former Oregon Bank and Security Pacific Bank of Oregon. Ms. Wasson was elected as Chair of the Boards of NW Holdings and NW Natural in August 2021. Ms. Wasson

2026 ANNUAL PROXY STATEMENT | 7

currently serves on the Board of Directors of Columbia Sportswear Company (Nasdaq: COLM), where she is Chair of the Audit Committee and serves on the Nominating and Corporate Governance Committee. Ms. Wasson formerly served on the boards of Oregon Health & Science University Foundation, Inc., OHSU Knight Cancer Institute, Portland Business Alliance, Greater Portland Inc., Portland Mall Management, Inc., SOLVE Founders' Circle and the American Red Cross-Oregon Trail Chapter and was past Chair of the Oregon Business Plan and Oregon Business Council. She also serves as a Senior Fellow at American Leadership Forum. Ms. Wasson holds a Bachelor of Science and Commerce degree in finance from Santa Clara University.

Ms. Wasson brings to the NW Holdings Board extensive experience in commercial banking, finance and accounting and remarkable local and regional experience. Ms. Wasson's management and leadership roles in the banking industry as well as her strong community presence position her to provide insight and advice to the Board on a wide range of financial, accounting, commercial and local and regional strategic matters, including, but not limited to, regulated industry, mergers and acquisitions, consumer and commercial businesses, public and government policy and relations, human capital management and diversity, media relations, marketing, change management and compliance. In addition, Ms. Wasson's service as Chair of the Audit Committee of Columbia Sportswear and prior service as Chair of the Audit Committee of NW Natural and NW Holdings highlights her substantial experience in finance and accounting matters, which has led the Board to determine that she is an "audit committee financial expert" as defined by the SEC rules. Ms. Wasson's experience enables her to provide valuable guidance to the Board on accounting, finance, risk oversight, business strategy and development, and corporate governance. Together with her background in commercial banking and regulation and her strong community ties, this experience strengthens the Board's collective knowledge, capabilities and expertise.

Class II Directors With Terms Expiring in 2028

Since September 2021, Ms. McDonough has been the owner of Quetzal Consulting, a business consulting firm. From 2018 to 2021, Ms. McDonough served as President and CEO of Oregon Business & Industry (OBI), Oregon's largest statewide general business organization, with members across the state representing a wide variety of industries. Before joining OBI, Ms. McDonough served as President and CEO of the Portland Business Alliance, Greater Portland's Chamber of Commerce for 14 years. Ms. McDonough previously worked in the energy industry for two decades, including as a Vice President, External Affairs, for PG&E National Energy Group and Vice President, Communications and External Affairs, for PG&E Gas Transmission Northwest, both companies being former operating units of San Francisco-based PG&E Corporation. Earlier, Ms. McDonough worked for PacifiCorp, holding positions in Oregon and Washington, D.C. Ms. McDonough currently serves on the boards of NW Natural and the non-profit New Avenues for Youth. She also serves on the Oregon advisory board for Regence and is a senior fellow of the American Leadership Forum/Oregon. She previously served on the Oregon advisory board for U.S. Bank National Association. She holds two bachelor's degrees from the University of Oregon.

Ms. McDonough brings to the NW Holdings Board extensive experience in governmental and public affairs through her leadership of OBI and the Portland Business Alliance, allowing her to contribute valuable insights on policy development and governmental relations. In addition, her strong community ties and familiarity with the Oregon business landscape position her to provide oversight on matters related to the local economy, business environments, and the communities served by NW Natural and NW Holdings. Her breadth of experience and leadership, including two decades of experience in the energy industry, positions her to provide insights to the Board and management on a wide variety of matters, including, but not limited to: utility operations, regulatory matters, change management, decarbonization, sustainability and climate change, and business development and strategy, all of which strengthen the Board's collective knowledge, capabilities and experience.

8 | NORTHWEST NATURAL HOLDING COMPANY

From 2005 to January 2009, Ms. Peverett served as President and Chief Executive Officer of British Columbia Transmission Corporation (BCTC), an electric utility in Vancouver, British Columbia. Between 2003 and 2005, she served as Chief Financial Officer of BCTC. Prior to joining BCTC, from 1988 through 2003, Ms. Peverett held various senior positions with Westcoast Energy Ltd., including serving as President and Chief Executive Officer of Union Gas Limited, a Westcoast Energy company, between 2001 and 2003. Ms. Peverett currently serves on the Boards of Directors of NW Natural, Suncor Energy Inc. (Suncor) ((NYSE: SU)(TSX: SU)), Capital Power Corporation (TSX: CPX), and Canadian Pacific Kansas City (formerly Canadian Pacific Railway Limited) ((NYSE: CP)(TSX: CP)). She currently serves as a member of the Audit and Finance Committee of Canadian Pacific Kansas City, where she previously served as Chair, on the Audit and Health, Safety & Environment Committees of Capital Power, and on the Audit and Governance Committees of Suncor. Ms. Peverett additionally serves as Chair of the CSA Group (formerly the Canadian Standards Association). Ms. Peverett has also previously served on the Board of Directors of Canadian Imperial Bank of Commerce (CIBC) ((NYSE: CM)(TSX: CM)) from 2009 to 2023. She has also previously served on the boards of Hydro One Inc., AEGIS, Encana Corporation, Postmedia Network Canada Corp., BC Ferry Authority, BC Ferries Services, Inc. (BC Ferries), and the United Way of Lower Mainland, also serving as Chair of BC Ferry Authority, Chair of the Corporate Governance Committee and a member of the Audit Committee at CIBC, and as Chair of the Audit Committee of Encana Corporation. Ms. Peverett earned a Bachelor of Commerce degree from McMaster University and a Master of Business Administration degree from Queen's University. She is a certified management accountant.

Ms. Peverett's extensive senior management experience at Union Gas Limited of Chatham, Ontario, a natural gas distribution, storage and transmission company, and BCTC, the entity responsible for managing British Columbia's publicly-owned electrical transmission system, as well as her board experience at Capital Power Corporation, a North American power producer, Suncor, a global integrated energy company, Canadian Pacific Kansas City and NW Natural, and her prior board experiences at Hydro One Inc., one of North America's largest electricity delivery companies, AEGIS, Encana Corporation, Postmedia Network Canada Corp., and BC Ferries, position her to provide oversight of and advise management on a wide range of natural gas and energy industry strategic and regulatory matters. In addition, Ms. Peverett's other board experiences, including as Chair of the Audit and Finance Committee of Canadian Pacific Kansas City, member of the Audit and Governance Committees of Suncor, former Chair of the Corporate Governance Committee and Audit Committee of CIBC, former Chair of the Audit Committee of Encana Corporation, and a former Audit Committee member of Postmedia Network Canada Corp., enable her to provide effective oversight of management and insight into a wide variety of corporate governance, risk oversight, change management, and financial matters. Ms. Peverett's extensive knowledge of and training in finance and accounting matters has led the Board to determine that she is an "audit committee financial expert" as defined by the SEC rules. Her cumulative experience strengthens the Board's collective knowledge, capabilities and experience.

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Since 1990, Mr. Wilhoite has worked for, and since 1995 has been a Managing Director of, Willamette Management Associates, Inc., a consulting firm in the fields of business valuation, forensic analysis, and transaction financial advisory services, which firm was acquired by Citizens Financial Group in September 2021. Before his tenure at Willamette Management Associates, Inc., he was a Senior Auditor at KPMG. Mr. Wilhoite currently serves as a member of the Board of Trustees of Meyer Memorial Trust, Board Chair of Legacy Health, and serves as a board member of NW Natural, the Jensen Quality Growth Fund (JENSX), Portland Metropolitan Chamber (formerly Portland Business Alliance), Oregon Business Council, W. Lease Lewis, 4G Clinical, and the National Association of Corporate Directors Northwest Chapter. He also serves as an advisory board member of Black Business Warehouse and was appointed by former Oregon Governor Kate Brown as a member of a blue-ribbon task force to evaluate state and local debt to the Oregon Public Employees Retirement System (PERS). Mr. Wilhoite has previously served as Commissioner and Chair of the Board of the Portland Development Commission (PDC) and the City Charter Review Commission. He is also a past Chair of the Portland Business Alliance, Oregon Health & Science University, SMART, Urban League of Portland, and Meyer Memorial Trust, past Chair of the Portland Police Bureau Budget Advisory Committee, and past Chair and member of The Nature Conservancy of Oregon, Inc. Mr. Wilhoite also previously served on the Boards of PacificSource Health Plans, U.S. Bank of Oregon, the Oregon State Bar, Jesuit High School Portland, Portland State University Foundation, Oregon Health & Science University Medical Group, the Oregon Housing Stability Council, Oregon Investment Council, and the Federal Reserve Bank of San Francisco-Portland Branch, and served as an Economic Advisory Council Member of the Federal Reserve Bank of San Francisco. Mr. Wilhoite earned a Bachelor of Science degree in accounting and a Bachelor of Science degree in finance, both at Arizona State University. He is a certified public accountant, with accreditations in business valuation and financial forensics. His other accreditations are from various financial governing bodies and include certifications in chartered global management accounting, management accounting, financial management, business valuation and appraisal, and fraud examination.

Mr. Wilhoite brings to the NW Holdings Board extensive experience, as well as financial accreditations, in business valuation, finance and accounting, developed from over 35 years of experience as a consultant with Willamette Management Associates, his position as a Senior Auditor with KPMG, and current and former service in numerous regional and local economic and business organizations, including the Federal Reserve Bank of San Francisco-Portland Branch, the Portland Business Alliance, the Oregon Business Council, the Oregon Housing Stability Council, the Portland Development Commission, and the Portland Police Bureau Budget Advisory Committee, positioning him to provide oversight and advice to the Company on financial, accounting, and strategy topics including, but not limited to, mergers and acquisitions, growth and diversification, risk and consumer and commercial businesses. Mr. Wilhoite also has served as Managing Director of Willamette Management Associates, Inc. for over three decades, thereby giving him entrepreneurial and marketing insight valuable to the Board. His experience in highly regulated industries, including his service as a member of the Boards of Directors of Legacy Health and Oregon Health & Science University, and his former service as a member of the Board of Directors of PacificSource, enables him to provide management oversight on subjects including public and government policy and relations, compliance and regulation. Furthermore, Mr. Wilhoite's strong community presence positions him to provide important guidance to the Board on local and regional strategic matters, and provides an important connection between NW Holdings and the communities it serves. Mr. Wilhoite's cumulative experience has led the Board to determine that he is an "audit committee financial expert" as defined by the SEC rules. Mr. Wilhoite's extensive knowledge and experience of finance, accounting and regulated industry, along with his strong community ties strengthen the Board's collective knowledge, capabilities and experience.

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From 2018 until her retirement in 2020, Ms. Ludford served as Deputy Chief Security Officer for Exelon Corporation, a provider of utility services in the United States. Ms. Ludford previously served as Vice President, Corporate Operations of Exelon from 2016 to 2018, and as Chief Audit Executive of Exelon from 2010 until 2016. At PECO Energy (an Exelon company), Ms. Ludford served from 2009 to 2010 as Vice President of Smart Grid and Smart Meters, as Vice President of Customer Operations from 2007 to 2009, and as Vice President Finance from 2006 to 2007. She additionally served as Vice President of Customer Financial Operations at Commonwealth Edison and PECO Energy from 2005 to 2006. Prior to 2005, Ms. Ludford held a variety of roles of increasing responsibility and complexity in the energy industry. Ms. Ludford currently serves on the Boards of NW Natural and Otter Tail Corporation (Nasdaq: OTTR), where she also serves on its Audit and Corporate Governance Committees. She holds a Master of Business Administration from the Quinlan School of Business at Loyola University Chicago and a Bachelor of Business from Western Illinois University.

Ms. Ludford's extensive senior management experience at Exelon Corporation positions her to provide valuable guidance and insight on a wide range of operational, strategic and regulatory matters impacting the energy and utility industries. In addition, her professional and board experience, including as a member of the Audit Committee of Otter Tail Corporation, enable her to provide important oversight of a variety of financial, accounting, auditing, risk management, change management, and cybersecurity matters. Ms. Ludford's cumulative experience has led the Board to determine that she is an "audit committee financial expert" as defined by the SEC rules. Ms. Ludford's extensive knowledge and experience in finance, accounting and energy and utility industry matters strengthen the Board's collective knowledge, capabilities and experience.

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Corporate Governance

THE BOARD OF DIRECTORS AND ITS COMMITTEES

Meeting Attendance

The Board of Directors conducts its annual organizational meeting on the same date as the Annual Meeting of Shareholders, which all of the directors are encouraged to attend. In 2025, 11 of our 13 then-current directors attended the Annual Meeting of Shareholders.

During 2025, there were seven meetings of the Board of Directors, each of which included an executive session of non-management directors. No director attended fewer than 75% of the aggregate meetings of our Board and Committees on which they served.

Independence

The Board of Directors has adopted Director Independence Standards to comply with New York Stock Exchange (NYSE) rules. The Director Independence Standards are available at www.nwnaturalholdings.com and are available in print to any shareholder who requests them. No director is deemed independent unless the Board affirmatively determines that the director has no material relationship with NW Holdings either directly or as a partner, shareholder or officer of an organization that has a relationship with NW Holdings. The Board applies NW Holdings' Director Independence Standards as well as additional qualifications prescribed under the listing standards of the NYSE and applicable state and federal statutes. Annually, the Board determines whether each director meets the criteria of independence, including whether the members of the Governance, Audit and Organization and Executive Compensation Committees (OECC) satisfy the independence requirement for service on those committees. As of February 26, 2026, the Board determined that nine of NW Holdings' eleven current directors met the independence criteria. They are directors Bragdon, Enand, Lee, Ludford, McDonough, Partain, Peverett, Wasson, and Wilhoite. The Board previously determined that directors Timothy P. Boyle, Dave McCurdy and Kenneth Thrasher, who each retired from the Board effective May 22, 2025, were independent.

Board Nominations and Refreshment

The Board is responsible for selecting candidates for Board membership and the Governance Committee has been assigned the responsibility of recommending to the Board of Directors nominees for election as directors. The Governance Committee, with recommendations and input from the Chair of the Board, the Chief Executive Officer (CEO) and other directors, evaluates the qualifications of each director candidate in accordance with the Director Selection Criteria established by the Board. Candidates for director nominees are reviewed in the context of the current composition and diversity of the Board, the operating requirements and existing and prospective business environment faced by NW Holdings, NW Holdings' business strategy, and the long-term interests of shareholders. Director candidates must be able to make a significant contribution to the governance of NW Holdings by virtue of their business and financial expertise, educational and professional background, and current or recent experience as a chief executive officer or other senior leader of a public company or other relevant organization. The business discipline that may be sought at any given time will vary depending on the needs and strategic direction of the Company and the experience represented by our incumbent directors. In addition, the Governance Committee looks at the overall composition of the Board and how a candidate would contribute to the overall synergy and collaborative process of the Board. In conducting its assessment, the Governance Committee considers a variety of criteria, including, but not limited to, the candidate's integrity, reputation, judgment, knowledge, experience, commitment, skills, diversity of background and experience, and independence.

In recent years, the Board undertook a comprehensive succession planning and refreshment review in anticipation of the retirements of several long-tenured directors. In line with those plans, the Board has undergone substantial refreshment, with four of the eleven current directors being added to the Board within the last five years.

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Shareholder Nominations

Shareholders' recommendations for director-nominees may be submitted to NW Holdings' Corporate Secretary for consideration by the Governance Committee. In evaluating shareholder recommendations for director-nominees, the Governance Committee applies the same Director Selection Criteria discussed above. NW Holdings' Restated Articles of Incorporation provide that no person, except those nominated by the Board, shall be eligible for election as a director at any annual or special meeting of shareholders unless a written request that their name be placed in nomination, together with the written consent of the nominee, and received from a shareholder of record entitled to vote at such election by the Corporate Secretary of NW Holdings on or before the later of (a) the thirtieth day prior to the date fixed for the meeting, or (b) the tenth day after the mailing of the notice of that meeting. Shareholders who wish to nominate directors in accordance with the procedures of our Restated Articles, Amended and Restated Bylaws (Bylaws) and Rule 14a-19 under the Securities and Exchange Act of 1934, as amended, should refer to "2027 Annual Meeting of Shareholders" on page 69 of this Proxy Statement for further information.

Board Diversity

As indicated above, NW Holdings' Director Selection Criteria includes a consideration of diversity as a factor in evaluating candidates for Board membership, including with respect to factors such as background, experience, skills, geographic location, race, gender, ethnicity, culture, veteran status, age, disability, and sexual orientation. Currently, of the eleven members of the Board, six directors are women, including the Chair of the Board, three directors identify as racially or culturally diverse, one director is a military veteran, and four directors are from a geographic location other than Portland, Oregon. The Governance Committee believes that, as a group, the nominees presented for election at the 2026 Annual Meeting of Shareholders effectively contribute to the Board's diverse range of backgrounds, experiences, skills and perspectives.

Board Experience

The NW Holdings Board consists of eleven directors with extensive professional experience and a diverse array of skills. This diversity of experience provides our Board with a collective skill set that is advantageous to the Board's oversight of our business and operations. In addition to the qualifications required of all directors that are set forth in NW Holdings' Director Selection Criteria, our Board members have experience in the following areas, among others:

NW HOLDINGS DIRECTOR EXPERIENCE*

For a more detailed description of each director's experiences, please see the director biographies above.

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Board Leadership Structure

The current Board leadership structure separates the roles of Chair and CEO. The Board evaluates its leadership structure and role in risk oversight on an ongoing basis. The decision to combine or separate the Board Chair and CEO roles is determined on the basis of what the Board considers to be best for NW Holdings at any given point in time. Currently, the independent Chair of the Board meets regularly with the CEO and the Corporate Secretary to discuss appropriate business to come before the Board and its committees and recommends agenda items for Board meetings. NW Holdings' Board is structured to promote independence. The directors of the Board meet regularly in executive sessions at which the independent Board Chair presides and only the non-management directors are present. In 2025, NW Holdings also held an executive session composed solely of independent directors, in accordance with NYSE rules.

Under NW Holdings' Bylaws, the Governance Committee, Audit Committee and Organization and Executive Compensation Committee must be composed entirely of independent directors and the Finance Committee and Public Affairs and Environmental Policy Committee must have a majority of independent directors. All committees have an independent chair that works with the executive officer primarily responsible for work with that committee and the Corporate Secretary to discuss appropriate business to come before the committee, and to recommend agenda items for that committee. The Board of Directors believes its leadership structure provides for appropriate independence between the Board and management.

The Governance Committee and the Board annually review the Corporate Governance Standards, which can be accessed electronically in the "Governance" section of NW Holdings' website at www.nwnaturalholdings.com, and the performance of the Board is reviewed annually by the members of the Board.

Board's Role in Risk Oversight

NW Holdings' management is responsible for the day-to-day management of risks faced by the Company, while the Board of Directors, collectively and through its committees, has responsibility for the oversight of risk management. The Corporate Governance Standards describe the Board's primary responsibilities, which include oversight of NW Holdings' mission, and key programs that enable the Board to assess and manage material risks including, but not limited to, risks related to business continuity and disaster response, strategy and business development, business improvement and technology, customer demand and market competition, gas procurement, pricing and hedging, gas distribution and storage operations, water, wastewater and water services operations, renewables operations, environmental and climate change matters, economic environment and financing, effective governance, legislative and regulatory risk and compliance, state and federal regulatory process and environment, financial performance, business integrity and compliance, financial statements and internal controls, pensions and retirement plans, reputational risk, human capital management, compensation and employee benefits, succession planning (including the CEO), human risks, and Company culture. Committee oversight authority with respect to risk management is described in more detail below. The Governance Committee and the Board periodically review its committee oversight authority to ensure the Board has adequate visibility and oversight of the Company's key areas of risk. Appropriate members of management serve as liaisons to Board committees, attend Board and committee meetings and regularly discuss with the Board and the committees various risks confronting the Company.

Management reports regularly to the Board on significant risk categories. Additional review or reporting on enterprise risks is conducted as needed or requested by the Board. The Board and management consider enterprise risks and opportunities in their strategic and capital spending decision process.

Committees

There are five standing committees of the Board: Audit, Finance, Governance, Organization and Executive Compensation (OECC), and Public Affairs and Environmental Policy (PAEPC). Each of the standing committees operates according to a formal written charter, all of which are reviewed annually and are available at www.nwnaturalholdings.com. Copies of the charters are also available in print to any shareholder upon request. The performance of each committee is reviewed annually. Each committee may obtain advice and assistance from internal or external legal, accounting or other advisors, when appropriate. Each committee has the opportunity to meet in executive session with non-management directors at each committee meeting; the independent Chair of the committee presides at these sessions. Each committee regularly reports to the full Board of Directors.

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The table below shows the current membership of the Board and each standing committee and the number of meetings held during 2025.

AUDIT COMMITTEE

NW Holdings' independent Audit Committee, which regularly reports to the full Board, has primary responsibility for oversight and evaluation of the Company's policies with respect to significant risks and exposures faced by the Company and the procedures for assessing, monitoring and managing those risks, and reporting on those matters to the Board. The Audit Committee is responsible for overseeing matters relating to accounting, financial reporting, internal controls, auditing, information technology systems, cybersecurity and artificial intelligence, the Company's enterprise risk management process, business continuity and disaster planning, capital projects and contingencies, and material litigation. It is also responsible for the appointment, oversight and review of the Director of Internal Audit as well as the independent registered public accounting firm, and reviews the audit findings and other internal accounting control matters with the independent auditor. The Audit Committee also oversees the Company's Business Integrity Program, including the Code of Ethics, and the Company's system for review and treatment of the Company's Business Integrity Hotline complaints regarding accounting or financial irregularities as well as other compliance and integrity concerns. It also periodically reviews transactions with related parties, as discussed below under "Transactions with Related Persons," and policies relating to the delegation of management authority. In fulfilling its risk oversight function, the Audit Committee periodically, and as needed, discusses key risks with NW Holdings' Chief Executive Officer and President, Chief Financial Officer, Chief Accounting Officer, General Counsel and Chief Compliance Officer, legal counsel, internal auditors, and the Company's independent registered public accounting firm. A more detailed description of the Audit Committee's responsibilities is included in the "Report of the Audit Committee," below.

FINANCE COMMITTEE

The Finance Committee is responsible for reviewing strategies and making recommendations to the Board with respect to NW Holdings' financing programs, budgets and forecasts, financial policy matters, including hedging policies and practices, capital structure, dividend policy and material regulatory actions and issues as they relate to the Company's financial results, strategy and forecasts. It makes quarterly recommendations to the Board regarding payments of dividends, and periodically reviews financial reports by management and benchmarking financial performance against peers. The Finance Committee also oversees risks related to the economic environment, gas supply and pricing and carbon credit pricing and procurement, and provides oversight of the Company's investor relations program, credit agency and NYSE relationships, as well as the Company's retirement plans and funding status. The Finance Committee charter also provides that the Finance Committee will make recommendations to the

2026 ANNUAL PROXY STATEMENT | 15

Board as to the finance aspects of corporate development strategies, such as the acquisition or disposition of business and capital assets.

GOVERNANCE COMMITTEE

The Governance Committee is empowered, during intervals between Board meetings, to exercise all of the authority of the Board in the management of NW Holdings, except as otherwise may be provided by law. The Governance Committee, which serves as the nominating committee, makes recommendations to the Board regarding nominees for election to the Board and committee composition and structure, establishes criteria for Board and committee membership and policies that govern the Board's activities, reviews and recommends to the Board governance policies and structure, including the Corporate Governance Standards discussed below, evaluates Board and individual director performance and oversees director onboarding and continuing director education. The Governance Committee annually evaluates executive and director stock ownership guidelines and directors' and officers' ownership levels. The Governance Committee also reviews and makes recommendations to the Board regarding Board compensation. It also considers Board succession plans and any questions of possible conflicts of interest of Board members and senior executives, as well as director independence, and, jointly with the OECC, considers CEO succession plans. The Governance Committee is also responsible for oversight of NW Holdings' integrated environmental, social and governance matters.

ORGANIZATION AND EXECUTIVE COMPENSATION COMMITTEE

The Organization and Executive Compensation Committee is charged with oversight of the Company's human capital management. It oversees and reviews plans and preparations for talent succession, including, jointly with the Governance Committee, CEO succession; manages risks associated with the transfer of knowledge and expertise of the Company's workforce; with input from the full Board, reviews the performance of the CEO; considers the performance of other executive officers; makes recommendations to the Board relating to executive compensation programs and benefit plans, as well as monitoring risks related to such plans and programs; and reviews and approves grants under equity incentive plans to eligible employees. The OECC is primarily responsible for ensuring that executive compensation programs and plans are consistent with corporate objectives and the OECC's compensation philosophy. In fulfilling its compensation risk oversight function, the OECC discusses with its outside consultant key compensation design elements of the Company's compensation plans and awards, including, but not limited to, whether those plans and awards properly incentivize executive performance, attract and promote retention of valuable executives, and disincentivize inappropriate risk-taking. In addition to those matters delegated to the OECC by the Board, the OECC also makes recommendations to the Board regarding organization and executive succession matters. Each member of the OECC meets the criteria for a "non-employee director" under applicable SEC rules. For additional information regarding the OECC, see "Executive Compensation-Compensation Discussion and Analysis-Executive Compensation Policies and Practices," below.

PUBLIC AFFAIRS AND ENVIRONMENTAL POLICY COMMITTEE

The Public Affairs and Environmental Policy Committee reviews and monitors NW Holdings' significant legislative and regulatory matters as well as NW Holdings' policies and practices relating to significant public and political issues, including charitable and political contributions and budgets. It identifies and brings to the attention of the Board current and emerging political and societal trends. The PAEPC oversees our programs and policies relating to civic, human rights, charitable and community affairs, customer engagement, employee health and well-being, safety, access and inclusion, employee engagement, equal employment opportunities, and any other significant corporate social responsibility matters. It also reviews and recommends to the Board appropriate environmental policies and informs the Board concerning our sustainability efforts and the status of our compliance with environmental regulations, as well as oversees matters related to our environmental liabilities. It reviews the Company's environmental risks and the Company's plans for managing those risks.

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CORPORATE GOVERNANCE STANDARDS

The Board of Directors maintains Corporate Governance Standards, which are reviewed annually by the Governance Committee to determine if changes should be recommended to the Board of Directors. The Corporate Governance Standards are available at www.nwnaturalholdings.com, and in print to any shareholder who requests a copy. Among other matters, the Corporate Governance Standards include the following guidelines:

The Code of Ethics is available at www.nwnaturalholdings.com. Copies are also available in print to any shareholder who requests a copy. In addition, the Board of Directors has adopted procedures for the receipt, retention and treatment of concerns of our employees, shareholders, customers and other interested parties regarding accounting, financial reporting, internal controls, auditing or other matters. Concerns may be submitted in writing to the non-management directors of NW Holdings, c/o Corporate Secretary, 250 SW Taylor Street, Portland, OR 97204. Employees and other third parties may also submit concerns anonymously pursuant to the Integrity Hotline at 1-866-546-3696 or www.NWNIntegrity.com which is available through our external and internal websites. Our Chief Compliance Officer and Director of Internal Audit handle matters reported on the hotline and both regularly report to the Audit Committee regarding hotline activity, and the Chief Compliance Officer regularly reports to the Audit Committee regarding the Business Integrity program. All employees are required to annually complete an online education program about our Code of Ethics.

The Senior Vice President, General Counsel, Corporate Secretary and Chief Compliance Officer will refer concerns that come directly before her relating to accounting, financial reporting, internal controls or auditing matters to the Chair of the Audit Committee. She also regularly reports to the Governance Committee regarding concerns submitted to the non-management directors of NW Holdings, if any.

DELINQUENT SECTION 16(a) REPORTS

Section 16(a) of the Securities Exchange Act of 1934, as amended, requires the directors and executive officers of NW Holdings to file initial reports of ownership and changes in ownership of NW Holdings common stock with the SEC. Based solely on a review of the copies of reports furnished to us and written representations that no other such reports were required, we believe that during our fiscal year ended December 31, 2025, all directors and executive officers timely filed all reports required under Section 16(a) of the Securities Exchange Act of 1934, as amended, except the Form 4 filed on behalf of David H. Anderson on February 28, 2025 inadvertently omitted 2,588 shares of common stock sold pursuant to a Rule 10b5-1 trading plan. An amended Form 4/A was filed on March 26, 2025.

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COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION

Peter J. Bragdon, Hon. Dave McCurdy, Nathan I. Partain, Jane L. Peverett, Kenneth Thrasher, Malia H. Wasson and Charles A. Wilhoite each served as members of the OECC in 2025. No member of the OECC has been an executive officer of the Company, and no member of the OECC had any relationships requiring disclosure by the Company under the SEC's rules requiring disclosure of certain relationships and related-party transactions. None of the Company's executive officers served as a director or member of a compensation committee (or other committee serving an equivalent function) of any other entity, the executive officers of which served as a director or member of the OECC during 2025.

TRANSACTIONS WITH RELATED PERSONS

The Board adopted a written policy on the review of related person transactions (Related Party Transactions Policy), specifying certain transactions that involve directors, nominees, executive officers, significant shareholders and certain other related persons in which NW Holdings is or will be a participant, and that are of the type required to be reported as a related person transaction under Item 404(a) of SEC Regulation S-K, are subject to prior review by the Audit Committee. Pursuant to its charter, the Audit Committee is responsible for reviewing related person transactions.

Under the Related Party Transactions Policy, the Audit Committee reviews the material facts and circumstances of any transaction that may require reporting under Item 404(a) of SEC Regulation S-K to determine: (i) whether or not the transaction is on terms comparable to those that could be obtained in arm's length dealings with an unrelated third party; and (ii) whether or not the transaction is otherwise inconsistent with the interests of the Company and its shareholders. Upon review of a transaction, the Audit Committee may approve or disapprove entry into the transaction and direct the officers of the Company to take appropriate action. We are not aware of any transactions entered into during the last fiscal year that did not follow the procedures outlined in the policy.

Compensation to Son of Executive Officer

Sebastian Weber, the son of David A. Weber, Vice President, Gas Supply and Utility Support Services of NW Natural, has been an employee of NW Natural since February 2022. Mr. Sebastian Weber is currently employed as a Major Account Services Account Manager 2. Mr. David Weber was not involved in decisions regarding Mr. Sebastian Weber's hiring or compensation. Compensation paid to Mr. Sebastian Weber in 2025 was approximately $159,114 and is expected to be similar in 2026. Mr. Sebastian Weber does not report to Mr. David Weber, nor is Mr. David Weber in a position of oversight of Mr. Sebastian Weber. Compensation paid to Mr. Sebastian Weber is reviewed periodically by the Audit Committee in accordance with our Related Party Transactions Policy.

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SECURITY OWNERSHIP OF COMMON STOCK OF CERTAIN

BENEFICIAL OWNERS

The following table shows ownership of common stock of NW Holdings on December 31, 2025 by each person who, to our knowledge, owned beneficially more than 5% of NW Holdings common stock, as set forth in a Schedule 13G filed with the SEC:

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BENEFICIAL OWNERSHIP OF COMMON STOCK BY DIRECTORS

AND EXECUTIVE OFFICERS

Set forth below is certain information with respect to beneficial ownership of NW Holdings common stock as of December 31, 2025 by all current directors and nominees, each of the Named Executive Officers (NEOs) included in the Summary Compensation Table below and all directors and current executive officers as a group. For any directors or current executive officers who, as of December 31, 2025, (a) held shares in a deferred compensation account that would not have been distributed to them within 60 days after December 31, 2025 had their service terminated on that date, or (b) any other unvested rights to acquire NW Holdings common stock that were not scheduled to vest within 60 days after December 31, 2025, such shares or rights are not included in the table, but are included in the footnotes below.

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Executive Compensation

REPORT OF ORGANIZATION AND EXECUTIVE COMPENSATION COMMITTEE

The Organization and Executive Compensation Committee (OECC) of the Board of Directors of NW Holdings is responsible for discharging the responsibilities of the Board of Directors relating to the compensation of executives by ensuring that the Chief Executive Officer and other senior executives are compensated appropriately and in a manner consistent with the stated compensation philosophy of NW Holdings and the requirements of the appropriate regulatory authorities.

The OECC is responsible for producing this report and for providing input and guidance to management in the preparation of the Compensation Discussion and Analysis following this report. In fulfilling its responsibilities, the OECC has reviewed and discussed the Compensation Discussion and Analysis with management.

In reliance on the review and discussion referred to above, the OECC recommended to the Board of Directors (and it has approved and directed) that the Compensation Discussion and Analysis be included in this Proxy Statement and incorporated by reference into NW Holdings' Annual Report on Form 10-K for the year ended December 31, 2025.

Respectfully submitted on February 26, 2026 by the Organization and Executive Compensation Committee of the Board of Directors:

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COMPENSATION DISCUSSION AND ANALYSIS

This Compensation Discussion and Analysis (CD&A) describes the elements and objectives of our executive compensation program for 2025, the OECC's assessment of our pay for performance alignment, executive compensation roles and responsibilities, our compensation philosophy and practices, how executive compensation decisions are made, executive compensation plan components and design, and 2025 compensation results for each Named Executive Officer (NEO).

Named Executive Officers

Our NEOs for fiscal year 2025 were all employed by NW Natural and are as follows:

Executive Summary of 2025 Pay and Performance

2025 in Review

The OECC strives to align executive compensation with long-term shareholder value. In reviewing the totality of the circumstances for the short- and long-term award periods ending December 31, 2025, the OECC determined that the Company's compensation programs and payments align NEOs' interests with shareholders and appropriately incentivizes long-term shareholder value creation.

In 2025, NW Holdings' reported earnings per share (EPS) of $2.77, and achieved adjusted EPS of $2.93¹, compared to EPS of $2.03 and adjusted EPS of $2.33¹ for 2024. Management successfully executed on several key strategic initiatives, while maintaining our focus on safety, reliability and customer service, including:

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2025 Pay and Performance Highlights

The Company's executive compensation program aims to provide compensation that is competitive with our industry peers and appropriately awards the achievement of the Company's short and long-term performance goals. Our named executive officer compensation in 2025 consisted of (a) base salary, (b) annual cash incentive compensation under our Executive Annual Incentive Plan (EAIP), (c) long-term incentive compensation comprised of Performance Share Awards (PSAs) and Restricted Stock Units (RSUs), and (d) other benefits as described herein.

ANNUAL INCENTIVES EARNED IN 2025

The Company's financial performance in 2025, together with management's execution of key strategic initiatives, resulted in average EAIP payouts to the NEOs of 138.8% of target, out of a maximum possible 175%. The EAIP is weighted 70% based on the Company Performance Factor (comprised of 71.43% Net Income Factor and 28.57% Operations Factor) and 30% Priority/Individual Goals.

For 2025, Net Income, as adjusted by the OECC,² was $122,136,940, corresponding to 139.4% achievement out of a maximum 175% for the Net Income Factor. Management further achieved 126.2% out of a possible 175% on the Operations Factor, and NEOs earned an average of 145.3% out of a possible 175% for the Priority/Individual Performance Factor.

LONG-TERM INCENTIVES EARNED IN 2025

Long-term incentive targets for NEOs are generally allocated 65% of value to Performance Share Awards (PSAs) and 35% of value to Restricted Stock Units (RSUs). PSAs are not paid unless a return on invested capital (ROIC) threshold is met. Awards are based on achievement of a three-year cumulative earnings per share (EPS) target as modified by the Company's three-year total shareholder return (TSR) relative to a peer group. The three-year average ROIC for the 2023-2025 performance share cycle, as adjusted³ by the OECC, was 5.95%, resulting in achievement of the performance threshold. Cumulative EPS for the three-year cycle was $7.90, as adjusted, resulting in a 119.6% payout factor. The Relative Total Shareholder Return Modifier resulted in a 100% payout, with the Company achieving a 14.79% TSR over the three-year period which ranked at the 36^th percentile of the TSR Peer Group designated by the OECC.

Performance-contingent RSUs do not vest unless NW Holdings' adjusted return on common equity (ROE) exceeds the average cost of long-term debt for the preceding five years. NW Holdings' ROE for 2025, as adjusted,⁴ was 8.39%, which was greater than NW Holdings' average cost of long-term debt for the preceding five years, which was 4.71%, resulting in vesting of outstanding RSUs scheduled to vest in 2026 for 2025 performance.

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Key OECC Actions in 2025

One central responsibility of the OECC is to develop a plan and process for CEO succession and selection in collaboration with the Governance Committee, and to oversee executive officer succession planning and development. In anticipation of Mr. Anderson's retirement, the OECC and Governance Committee devoted substantial time and discussion to succession planning over the past several years. On May 23, 2024, Mr. Anderson informed the Board of his decision to retire from his position as CEO of NW Holdings and NW Natural effective April 1, 2025, and the Board designated Mr. Palfreyman as successor to the office of CEO. Mr. Anderson retired on April 1, 2025, and Mr. Palfreyman was appointed as CEO and President of NW Holdings and CEO of NW Natural effective at such time.

The OECC also executed on executive succession plans by:

For 2025, the OECC retained its overall incentive design, including the continued use of both financial and operational performance metrics in annual incentive awards. For long-term awards, PSAs continued to be based on three-year cumulative EPS, as modified by the Company's three-year TSR relative to a peer group, reinforcing the long-term focus of the program. RSUs were generally performance-based and do not vest unless NW Holdings' adjusted ROE exceeds the average cost of long-term debt for the preceding five years.

Executive Compensation Policies and Practices

Our executive compensation and corporate governance policies and programs are designed to closely tie executive pay to company performance and drive long-term shareholder value without encouraging inappropriate risk-taking.

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To achieve our objectives, we have adopted the following policies and practices over time:

Executive Compensation Decision-Making Process

The Organization and Executive Compensation Committee (OECC), composed entirely of independent, non-employee directors, is responsible for establishing our compensation philosophy and practices, and develops, reviews and approves the compensation of the Company's executive officers. The Board has delegated to the OECC authority to grant equity awards under the LTIP and to approve executive officer compensation, except the CEO's cash compensation, which is approved by the full Board.

Compensation Philosophy and Guiding Principles

When making compensation decisions, the OECC applies its Executive Total Remuneration Philosophy and Guiding Principles (Compensation Philosophy) to guide executive compensation decisions. Each year, the OECC approves and updates the Compensation Philosophy as needed. Its guiding principles are to design executive compensation programs that:

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Among other practices, the OECC:

Role of Management

Management supports the OECC to facilitate executive compensation decisions, including working with the compensation consultant engaged by the OECC and legal counsel on plan design changes, preparing reports and materials, communicating with outside advisors, administering plans on a day-to-day basis with oversight by the OECC, including providing information about the Company's performance relative to incentive plan goals, and implementing the Board's and OECC's decisions. The Vice President and Chief People Officer currently serves as the primary management liaison to the OECC. The CEO makes recommendations to the OECC regarding plan design, salary increases, incentive awards and other compensation decisions for executives other than himself, but he does not participate in discussions concerning his own compensation.

Role of the Compensation Consultant

For 2025, the OECC engaged Pay Governance, an independent compensation consulting firm (Consultant), to provide guidance to the OECC on the design, operation and competitiveness of our compensation programs. The Consultant reports directly to the OECC Chair. At the direction and under the guidance of the OECC Chair, the Consultant provides data and analysis that is used to develop recommendations for executive compensation programs to submit to the OECC for its consideration. Among other matters, the Consultant provides advice regarding:

The OECC reviews the engagement, performance and independence of its Consultant periodically, and as part of that process, reviews a summary of all services provided to NW Holdings by the Consultant, the percentage of the total fees paid by NW Holdings in relation to the total revenues of Consultant, any business or personal relationships the Consultant may have with any member of the OECC or any executive officer of NW Holdings, NW Holdings stock owned by the Consultant or any member of Consultant working on the NW Holdings account, and internal

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policies and procedures of the Consultant in place to maintain the objectivity, independence and separation between compensation consulting and investment advisory services, including, but not limited to, the Consultant's code of business conduct requirement that all the Consultant's associates must report any potential conflicts of interest. The Consultant does not provide any services to NW Holdings other than executive compensation consulting.

Results of 2025 Shareholder Advisory Vote on Executive Compensation

At the Annual Meeting of Shareholders held May 22, 2025, over 96% of the shareholder votes cast on the resolution approving the compensation of the NEOs, without regard to abstentions as provided under Oregon law, were cast in favor of the resolution. The OECC considered the level of support indicated by that vote as reflecting favorably on our executive compensation system and determined that no changes in response to the vote were needed.

How Compensation Decisions Are Made

Guided by its Remuneration Philosophy and Company performance, the OECC begins by reviewing each component of executive compensation for the NEOs using the median of peer proxy data, energy service company survey data, and general industry survey data as guides for each relevant position. For 2025, the Consultant recommended, and the OECC approved, a peer group of the following 18 gas, electric, water and combination utilities, based on industry, company type/geography, size (including revenues and market capitalization) and other qualitative factors.

For 2025, the OECC selected the following companies to serve as our compensation peer group, and the Consultant provided compensation data from the most recent proxy statements of these peer companies:

For 2025, the Consultant also presented a blend of two sets of survey data, for companies identified in the Willis Towers Watson (WTW), Energy Services Executive Compensation Database, 2024, which covers comparable energy companies with revenues less than $3 billion (identified in Exhibit A), and the WTW, General Industry Executive Compensation Database, 2024, which covers comparably sized companies (identified in Exhibit B). Survey data is formulated based on functional responsibilities of each NEO's position. The Consultant also used the American Gas Association Compensation Survey, 2024 as a reference. The Consultant selects the most appropriate market comparisons for each executive position and synthesizes that data to provide to the OECC for its review. At that time, the Consultant recommends levels for each compensation component for each relevant position, including circumstances when other data, or adjustments to presented data, may be a more appropriate guide.

The OECC also considers a number of factors beyond applicable median market information, all of which inform, but none of which individually dictate, the OECC's decisions, including the following:

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Elements and Objectives of our Executive Compensation Program for 2025

The following is a summary of our 2025 executive compensation program:

2025 Allocation of Current versus At-Risk Compensation

We believe our executive compensation programs provide executive officers with a balanced mix of market-competitive base salaries and pay "at risk". The majority of our executives' pay is in the form of variable compensation that is "at risk" based on achieving short-term and long-term performance goals, which are designed to drive shareholder value. At risk components include annual incentive cash awards and long-term incentive awards which include Performance Share Awards (PSAs) and restricted stock units (RSUs). The portion of total direct compensation designed to be paid in base salary versus pay at risk depends upon the executive's position and the ability of that position to influence outcomes, as well as market factors. The CEO has the largest portion of pay at risk.

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The charts below illustrate the components of target total direct compensation in 2025 for the CEO and for the other NEOs. Pay at risk represented 74% of total target direct compensation for the CEO and averaged 60% for the other NEOs.

2025 Target Total Direct Compensation Mix^{(1), (2), (3)}

Overview of CEO Compensation

The following table shows the OECC's target value for each component of our current CEO's 2025 compensation along with information regarding the applicable median market for each component of compensation and the CEO's total compensation. As illustrated, the OECC set Mr. Palfreyman's targeted total compensation approximately 11% below the median of the applicable market data.

Further information regarding Mr. Palfreyman's components of compensation and actual amounts paid are provided below, along with similar information for the other NEOs.

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Components of Compensation

Base Salaries

The following table shows the salaries of the NEOs before and after salary adjustments went into effect on March 1, 2025, and with subsequent salary adjustments in connection with organizational changes, as applicable.

As part of its salary review, the OECC considered applicable market data for each NEO's functional position and areas of responsibility and applied an adjustment to Mr. Kaszuba's position, reflecting his additional responsibilities for the information technology, business development, project management office and purchasing; an adjustment to Ms. Saathoff's position comparator to reflect additional responsibilities of rates, regulatory affairs and security and facilities; and an adjustment to Ms. Rush's position comparator to reflect additional responsibilities for NW Natural profit and loss oversight and serving as the public face of the gas company. The OECC set base salaries for all NEOs after application of these adjustments and consideration of applicable median market information and other relevant factors, including each NEO's areas of responsibility, professional experience and tenure.

Executive Annual Incentive Plan

The EAIP ties executive pay to achievement of annual financial, operating and individual performance goals.⁵ Participation in the EAIP, as of December 31, 2025, was limited to 14 participants, who were all employed by NW Natural, including the NEOs. Awards approved by the OECC are paid by March 15 of the following year, and are subject to "clawback" under the Company's Compensation Recovery Policy.

Target and actual awards in dollars, for 2025 incentive awards paid in 2026, are set forth in the table below.

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In determining total cash compensation (salary plus target annual award), the OECC considered each NEO's functional position and areas of responsibility and applied the same adjustments to Mr. Kaszuba's and Mses. Saathoff's and Rush's positions that were applied for purposes of base salary. The OECC set target total cash compensation after application of these adjustments and consideration of applicable median market information and other relevant factors, including each NEO's areas of responsibility, professional experience and tenure.

The formula for the EAIP total incentive award is as follows:

The Net Income Factor and the Operations Factor represent 50% and 20%, respectively, of each participant's total EAIP award. The OECC sets the Net Income and Operations Factor goals, ranges and targets each year taking into account the current economic and regulatory environment, management's annual objectives, and the way in which those annual objectives fit within the larger strategic and growth goals for our businesses. Given the factors considered by the OECC, and the importance of retaining executive focus during challenging times, the ranges and targets may be higher or lower than in prior years.

The OECC has authority to authorize adjustments to performance measure calculations to take into account unanticipated circumstances or significant, non-recurring or unplanned impacts as the OECC determines is appropriate. The OECC retains this authority as a compensation plan risk mitigation strategy to avoid circumstances where EAIP goals could incent executive actions that would not be aligned with the best interests of our businesses or shareholders long-term. The OECC has authority to recommend an award increase up to a maximum of 175% of the target when goals are exceeded or to reduce an executive's performance-based award when goals are not achieved.

The OECC exercised its authority in 2025 by adjusting 2025 Net Income upward by $8.8 million to $122,136,940, reflecting the exclusion of transaction and business development costs, including fees and expenses incurred in connection with the acquisitions of SiEnergy and Pines as well as the exclusion of severance expenses incurred in the fourth quarter of 2025 in connection with certain workforce restructuring activities (collectively, the Net Income Adjustments).

In exercising this authority and consistent with its Compensation Philosophy, the OECC determined that management's compensation should not be impacted by costs incurred in advancing strategic initiatives that support the Company's long-term growth and shareholder value. In reaching this determination, the OECC noted that such costs were not reflected in the 2025 Net Income Factor Target approved by the OECC and were not indicative of core operating performance. Accordingly, the OECC determined that an adjustment was appropriate to preserve alignment between compensation outcomes and the OECC's objective of aligning executives' interests with those of NW Holdings' shareholders.

NET INCOME FACTOR

The NW Holdings Net Income Factor is used to align executives' interests with shareholders' interests and in recognition of the importance earnings have in influencing our future stock price. Net income results, as adjusted by the Net Income Adjustments, are interpolated to determine the corresponding performance factor, up to a maximum of 175%. For 2025, Net Income Factor levels were:

Amounts less than $106,022,026 result in a 0% payout factor.

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NW Holdings net income for 2025, as adjusted by the Net Income Adjustments, was $122,136,940, resulting in a Net Income Factor equal to 139.4%.

OPERATIONS FACTOR

The OECC selected NW Natural operating goals of significant importance to public and employee safety and customer satisfaction, as well as supporting profitability and productivity to comprise the Operations Factor. These operating goals are substantially aligned with the incentive programs for all non-bargaining unit NW Natural employees. While each goal can contribute a goal rating between 0 and 200% multiplied by the assigned goal weight based on actual results, the aggregate of the Operations Factor is limited to a maximum of 175%. Actual results are interpolated to determine the performance factor for each goal. The Operations Factor was determined using the following formula:

A summary of the operating goals for 2025, the weighting of each goal to the overall factor, and the 2025 goal performance rating achieved is set forth in the following table:

Lower-than-targeted meter growth was driven by a slowdown in residential new construction, reflecting broader economic and housing market conditions in NW Natural's service territory. Combined, our operating performance in 2025 resulted in an Operations Factor of 126.2%.

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PRIORITY/INDIVIDUAL PERFORMANCE FACTOR

Thirty percent of each NEO's annual incentive target award is based on the Priority/Individual Performance Factor determined by individual performance goals, which include some significant "stretch" goals. In the case of the CEO, individual goals are determined by the OECC in consultation with the CEO. Whether the CEO has attained his goals is determined largely based on the OECC's assessment, with input from the full Board, of the CEO's performance. The other NEOs' individual performance goals align with the CEO's goals and support our strategic plans. The 2025 priority goals from which executives derive their Individual Performance Factors included a range of goals across NW Holdings and its subsidiaries, including:

In addition to the above shared executive officer goals, Mr. Palfreyman identified 2025 CEO performance goals, which reflected NW Holdings' strategic objectives across its businesses and provided a framework for evaluating Mr. Palfreyman's performance through an enterprise-wide set of strategic, financial, operational and safety measures. These CEO goals included: continued effective leadership, including strengthening executive management team alignment, development, and succession planning, advancing strategy formulation and execution at NW Holdings and its subsidiaries, achieving targeted financial performance and operations and safety outcomes, and advancing the Company's regulatory and other stakeholder engagement.

The CEO evaluated the 2025 individual performance of each NEO on a scale from 0 to 175%, based on priority/strategic goals specifically identified for each NEO. A rating of 100% indicates goals, including a particular "stretch" goal, were met, while ratings between 100 and 175% indicate extraordinary performance or achievement of multiple "stretch" goals. The OECC, with input from the full Board, uses this same method of assessment to establish the year-end performance rating for the CEO. The OECC reviewed Mr. Palfreyman's performance during the year, noting particularly strong performance with respect to his goals related to leadership and strategy formulation and

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execution, and above target performance with regard to financial performance, regulation, operations and safety, and stakeholder relations goals. The OECC calculated Mr. Palfreyman's overall rating at 145.0% for Mr. Palfreyman's individual performance. Performance ratings of the other NEOs ranged from 125.0% to 163.1% reflecting strong performance on individual goals in a challenging environment.

Together with the Net Income Factor of 139.4% and Operations Factor of 126.2%, the priority/individual performance of the NEOs resulted in an overall average payout under the EAIP of 138.8% out of a possible 175% of target.

Long-Term Incentives

The OECC considered the financial performance and alignment of NEO interests with shareholders when making decisions regarding long-term incentives. Specifically, the OECC noted:

In 2025, the long-term incentive portion of our executive compensation program consisted of two components: RSUs with performance threshold and Performance Share Awards (PSAs). For purposes of setting the targeted value of long-term incentives, the OECC uses the market price of NW Holdings common stock near the grant date. The OECC targeted an allocation of long-term incentive value for 2025 at approximately 35% RSUs with a performance threshold and 65% PSAs. The OECC believes the allocation between RSUs with a performance threshold and PSAs provides a balanced performance focus for executives.

The targeted value of long-term incentives granted to the NEOs in 2025 were informed by the same considerations as all other components of compensation, and are displayed in the below table.

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PERFORMANCE SHARES

The first component of our executives' long-term compensation program is provided through Performance Share Awards (PSAs) under our LTIP. All of the NEOs participated in the PSA program in 2025, except for Mr. Anderson, who did not receive a long-term award in light of his planned retirement. The agreement for PSAs "claws back" any erroneously inflated payouts pursuant to NW Holdings' Compensation Recovery Policy.

PSAs are determined by multiplying the targeted PSA by a Performance Share Factor. For the 2025-2027 performance cycle (and 2024-2026 and 2023-2025 performance cycles), PSAs are determined as follows:

ROIC Performance Threshold

A three-year average ROIC threshold was established to focus executives on long-term return on invested capital, given the amount of capital that is deployed in utility operations. ROIC for each year in the performance period is defined as (i) NW Holdings' net income for the year before interest income and expense divided by (ii) NW Holdings' adjusted average long-term capital, consisting of the average of NW Holdings' opening and closing shareholders' equity plus long-term debt for the year. The average ROIC is then the average of the adjusted ROICs achieved in each of the three years of the performance cycle. In order for PSAs to be paid, the ROIC threshold must be satisfied. For PSAs made in 2025, the ROIC threshold is 4.63%. For PSAs made in 2024, the ROIC threshold is 4.26%. For PSAs made in 2023, the ROIC threshold is 4.21%.

Once the ROIC threshold is met, the Performance Share Factor is determined by the following formula:

3-Year Cumulative EPS Component

Three-Year Cumulative EPS was chosen to align executives' interests with shareholder interests and to drive a focus on earnings over the three-year period. For this purpose, EPS is defined as NW Holdings' diluted earnings per share. Performance is based on an EPS achievement percentage calculated by dividing NW Holdings' cumulative EPS over the three-year performance period by the sum of the EPS targets set by the OECC during each of the three years in the performance period. The OECC determined to set EPS targets on an annual basis in February of each year of the cycle in light of the Company's evolving business plan and the timing of investments and strategic initiatives, while still maintaining a cumulative, multi-year performance framework. The EPS payout factor is based on cumulative EPS achievement percentage as follows:

3-Year Relative Total Shareholder Return (TSR) Modifier

Relative TSR was chosen because it aligns executives' interests with those of shareholders, as this is the amount a shareholder might receive from ownership in NW Holdings. Relative TSR measures the change in share price, assuming dividends are reinvested over the three-year period, using the three-month average daily closing price immediately prior to the start of the performance period and prior to the end of the performance period. The Relative TSR peer group consists of a designated peer group of natural gas local distribution companies and gas/electric utilities that continue to have publicly-traded common stock through December 31 of the final year of the 3-year performance cycle, excluding any peer company that is party to a signed acquisition agreement pursuant to which the stock or substantially all of the assets of the peer company will be acquired by a third party. The Relative TSR peer group for the 2025-2027, 2024-2026 and 2023-2025 performance cycles was selected by the OECC in

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consultation with the Consultant based on their comparable market capitalization, notable gas utility operations and strong trading correlations with NW Holdings and consists of the following companies:

Relative TSR modifier levels are based on the percentile rank of our TSR as compared to the TSR peer group and are as follows:

For the same reasons the OECC retained authority under the EAIP to adjust for certain extraordinary, non-recurring or unplanned impacts as the OECC determines is appropriate, the OECC designed the ROIC performance threshold and EPS component of the PSAs to permit the OECC to approve adjustments to take into account unanticipated circumstances or significant non-recurring or unplanned events, including but not limited to adjustments to eliminate the impact of changes in accounting principles, gain or loss on the sale of a business, impairments, tax impacts or tax rate changes.

2023-2025 Performance Share Results

The Performance Share Factor for this period resulted in 119.6% of target, or 59.8% of a possible 200% total opportunity. Minimum, target, maximum and actual share awards for the 2023-2025 PSAs are set forth in the table below.

PSAs are performance-based and are not paid unless a ROIC threshold is met. Awards are based on achievement of a three-year cumulative EPS target as modified by the Company's three-year TSR relative to a peer group.

For the 2023-2025 performance share cycle, the OECC exercised the same adjustment authority applicable to PSAs that it retains under the Executive Annual Incentive Plan.

For 2024, the OECC adjusted the EPS and ROIC components of the PSAs to exclude the impact of a $10.1 million after-tax non-cash charge resulting from the disallowance of undepreciated line extension costs ordered in NW Natural's 2024 Oregon general rate case, as well as transaction expenses incurred in connection with the

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Company's acquisition of SiEnergy. The OECC concluded that these items were not indicative of core operating performance, and, with respect to the 2024 regulatory disallowance, was outside of management's control.

Similarly, for 2025, the OECC adjusted the EPS and ROIC components to eliminate the impact of transaction and business development costs, including fees and expenses incurred in connection with the acquisitions of SiEnergy and Pines in 2025. For 2025 the OECC also excluded certain severance expenses incurred in the fourth quarter of 2025 in connection with workforce restructuring actions. The OECC determined that these costs advanced strategic initiatives undertaken to support the Company's long-term growth and operational efficiency and, accordingly, management should not be discouraged from pursuing such initiatives.

Combined, these "Performance Share Adjustments" increased cumulative EPS by $0.51 and increased Average ROIC by 0.21%. In exercising this authority and consistent with its Compensation Philosophy, the OECC sought to align incentive compensation outcomes with core operating performance, while neither insulating management from performance accountability nor discouraging the pursuit of strategic actions that the OECC believes are in the best interests of the Company and its shareholders.

ROIC Performance Threshold

For the 2023-2025 performance cycle, the three-year average ROIC threshold, which must be satisfied in order for the cycle to pay out, was set at 4.21%. The three-year average ROIC for the performance period was 5.74%, and as adjusted by the Performance Share Adjustments, on a non-GAAP basis, was 5.95%, resulting in achievement of the ROIC performance threshold.

3-Year Cumulative EPS Component

For the 2023-2025 performance cycle, the cumulative EPS Payout Factor was determined based on the following:

EPS results between any two data points are interpolated. Amounts less than $7.26 result in a 0% payout factor.

3-Year Cumulative EPS for the 2023-2025 performance cycle was $7.39, and as adjusted by the Performance Share Adjustments, on a non-GAAP basis, was $7.90, resulting in a Cumulative EPS factor equal to 119.6%.

3-Year Relative Total Shareholder Return (TSR) Modifier

The Relative TSR peer group for the 2023-2025 performance cycle consisted of a designated peer group of eleven natural gas local distribution companies and gas/electric utilities that continued to have publicly-traded common stock through December 31, 2025. One of the original 12 peer companies approved by the OECC at the beginning of the 2023-2025 performance cycle was acquired in 2023 and as such, was not included in the Relative TSR peer group for purposes of calculating relative TSR results. For the 2023-2025 performance cycle, the Relative Total Shareholder Return Modifier resulted in a 100% payout with the Company achieving a 14.8% TSR over the three-year period which ranked at the 36^th percentile of the TSR Peer Group designated by the OECC.

RESTRICTED STOCK UNITS

Performance-Contingent RSUs

The second component of our executives' long-term compensation program is provided through Restricted Stock Units (RSUs) under our LTIP. At its meeting each February, the OECC grants performance contingent RSUs under the LTIP. This practice gives the OECC the benefit of considering the relative value of all components of each executive's total compensation.

An RSU obligates NW Holdings upon vesting to issue to the RSU holder one share of common stock plus a cash payment equal to the total amount of dividends paid per share between grant and vesting of the RSU. The performance threshold for the RSUs will be met on each vesting date if NW Holdings' ROE for the preceding year is greater than NW Holdings' average cost of long-term debt for the preceding five years. No RSUs with a performance threshold will vest in a given year if the performance threshold is not met, and shares subject to vesting in that year will be forfeited. For Performance-Based RSUs awarded in 2025, if the performance threshold is met, RSUs vest for

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one-third of the awarded shares on March 1 of each of the first three years after the grant date. For Performance-Based RSUs awarded in prior years, if the performance threshold is met, RSUs vest for 25% of the awarded shares on March 1 of each of the first four years after the grant date. For purposes of calculating ROE, the OECC may, at any time, approve adjustments to the calculation of ROE to take into account such unanticipated circumstance or significant, non-recurring or unplanned events as the OECC may determine in its sole discretion, and such adjustments may increase or decrease ROE. The OECC exercised the same discretion as to net income for purposes of calculating ROE as previously described for the EAIP. NW Holdings' ROE for 2025 was 7.92% and as adjusted by the Net Income Adjustments, was 8.39%, which was greater than NW Holdings' average cost of long-term debt for the preceding five years, which was 4.71%, resulting in the satisfaction of the performance threshold and vesting of outstanding RSUs scheduled to vest in 2026 for 2025 performance.

Time-Based RSUs

The OECC may grant off-cycle RSUs to attract new employees, to reward extraordinary performance, for retention purposes, or in recognition of promotions. Depending on the circumstances, these off-cycle grants may not include a performance threshold, and may include a vesting schedule that differs from the standard RSU with performance threshold vesting schedule. Mr. Kaszuba, as part of his initial attraction and retention package, received a grant of 7,815 RSUs without a performance threshold scheduled to vest ratably on September 1 of each of 2025, 2026, and 2027, subject to continued employment. Likewise, as part of her initial attraction and retention package, Ms. Berge received a grant of 6,297 RSUs without a performance threshold, scheduled to vest ratably on March 1 of each of 2026, 2027, and 2028, subject to continued employment.

Perquisites and Benefits

PERQUISITES

The OECC eliminated routine perquisites for executives effective January 1, 2008. The OECC acknowledges that certain benefits incidental to other business-related activities may continue, but the aggregate annual value of such benefits is not expected to regularly exceed $10,000 for any NEO. Examples of when perquisites may exceed $10,000 are when an individual is promoted to a more senior position, or as part of an initial hire package for a senior level executive.

ATTRACTION AND RETENTION PACKAGE FOR MS. BERGE

In an effort to attract and retain Ms. Berge, the OECC approved in 2025 certain one-time payments and benefits to Ms. Berge, including: a relocation cash payment of $125,000 and a grant of 6,297 RSUs that was previously described.

QUALIFIED AND NON-QUALIFIED RETIREMENT (DEFINED BENEFIT) PLANS

Mr. Anderson and Ms. Rush participate in the NW Natural Retirement Plan for Bargaining Unit and Non-Bargaining Unit Employees (Retirement Plan), a qualified defined benefit pension plan, on the same terms as other salaried employees. Mr. Palfreyman, Mr. Kaszuba, Ms. Saathoff and Ms. Berge joined NW Natural after 2006, when the Retirement Plan was closed to new employees. NW Natural also maintains the Supplemental Executive Retirement Plan (SERP), a non-qualified supplemental retirement plan for certain executives participating in the Retirement Plan. This plan is more fully described below under the "Pension Benefits as of December 31, 2025" table and the related narrative discussion. As discussed there, in 2009 the OECC recommended and the Board approved amendments to this plan that moderate the growth in benefits payable under this plan, and the SERP was closed to new participants, effective July 31, 2019.

QUALIFIED AND NON-QUALIFIED DEFERRED COMPENSATION (DEFINED CONTRIBUTION) PLANS

NW Natural also maintains both tax-qualified and non-tax-qualified defined contribution plans in which the NEOs are eligible to participate. The 401(k) Plan is a tax-qualified defined contribution plan and the NW Natural Deferred Compensation Plan for Directors and Executives is a non-tax-qualified deferred compensation plan. For further discussion of NEO participation in non-qualified deferred compensation plans in 2025, see the "Non-Qualified Deferred Compensation in 2025" table, below.

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REALIZED COMPENSATION TABLE

The SEC's calculation of total compensation, as shown in the Summary Compensation Table set forth on page 44, includes several items that are driven by accounting and actuarial assumptions, which are not necessarily reflective of compensation realized by the NEOs in a particular year. Similarly, the SEC's calculation of "compensation actually paid" set forth in the Compensation Actually Paid (CAP) Table set forth on page 47 includes annual adjustments to stock value for awards that NEOs may or may not ultimately receive, as well as pension service costs that may or may not be realized. To supplement the SEC-required disclosure, we have included the additional table below, which shows compensation actually realized by each NEO for each of the years shown. The OECC considers this calculation of realized compensation when making compensation decisions.

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SUMMARY COMPENSATION TABLE

The following is a summary of our NEOs' compensation in 2023, 2024 and 2025. Only a portion of the executive compensation shown in this Summary Compensation Table is included for purposes of establishing regulatory rates charged to customers. Although most of our incentive compensation programs are designed to promote shareholder objectives, our customers also directly benefit because many of the programs include performance incentives designed to improve service to our customers. For discussion regarding amounts excluded from rate recovery, see "Compensation Discussion and Analysis-Regulatory, Tax and Accounting Considerations-Regulatory Treatment," above.

Column (f) was deleted as it is not applicable.

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CEO COMPENSATION AND EMPLOYEE COMPENSATION

As a result of rules under the Dodd-Frank Wall Street Reform and Consumer Protection Act (Dodd-Frank Act), beginning with our 2018 proxy statement, the SEC requires disclosure of the ratio of CEO compensation, as calculated in the Summary Compensation Table (SCT), to the median compensation of all of the Company's employees other than the CEO. Mr. Palfreyman served as our CEO on December 31, 2025, the date selected to identify the median employee. The total compensation reported for Mr. Palfreyman differs from the Total column of the SCT as a result of the annualization of Mr. Palfreyman's compensation to reflect his mid-year appointment as CEO. Mr. Palfreyman's total compensation as reported in the SCT was $3,695,467, and his annualized compensation was $3,732,967. The difference between the annualized compensation and the Total column of the SCT reflects the annualization of Mr. Palfreyman's base salary. No other elements of compensation reported in the SCT were adjusted.

We estimate that the median annual compensation for all other employees of NW Holdings' subsidiaries, excluding Mr. Palfreyman, was $134,311 for 2025, calculated as though it were to be presented in the SCT. As a result, we estimate that Mr. Palfreyman's compensation was approximately 28 times that of the median annual compensation for all employees in 2025.

Our CEO to median employee pay ratio is a reasonable estimate calculated in a manner consistent with SEC requirements. We identified the median employee by examining the 2025 compensation for all individuals, excluding our CEO, who were employed by NW Holdings' subsidiaries on December 31, 2025. We included all employees, whether employed on a full-time, part-time, or seasonal basis. Pay elements that were included in 2025 compensation for each employee for purposes of identifying the median employee included salary or wages received in 2025; cash incentive bonuses received during 2025; the value of the performance share awards actually paid in 2025; and the value of RSUs vested and paid during 2025. Wages and salaries were annualized for employees who were not employed for the full year.

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