AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON OCTOBER 2, 2018

Registration No. 333-                    , 333-                    

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

Under

THE SECURITIES ACT OF 1933

One Pacific Square, 220 N.W. Second Avenue

Portland, Oregon 97209

503-226-4211

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

MARDILYN SAATHOFF

Senior Vice President and General Counsel

SHAWN M. FILIPPI

Vice President, Chief Compliance Officer and Corporate Secretary

One Pacific Square, 220 N.W. Second Avenue

Portland, Oregon 97209

503-226-4211

(Names, addresses, including zip codes, and telephone numbers, including area codes, of agents for service)

Approximate date of commencement of proposed sale to the public: From time to time after this Registration Statement becomes effective as determined by market conditions.

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

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

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

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

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

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

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

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of Securities Act.  ☐

CALCULATION OF REGISTRATION FEE

EXPLANATORY NOTE

This registration statement contains three (3) separate prospectuses:

Each offering of securities made under this registration statement will be made pursuant to one of these prospectuses, with the specific terms of the securities offered thereby (other than Common Stock offered under the Northwest Natural Holding Company Dividend Reinvestment and Direct Stock Purchase Plan) set forth in an accompanying prospectus supplement.

This registration statement is separately filed by Northwest Natural Holding Company and Northwest Natural Gas Company on a combined basis. As to each registrant, this registration statement consists solely of the prospectus of such registrant (including the documents incorporated therein by reference) and the information set forth in Part II of this registration statement that is applicable to such registrant. Neither registrant makes any representation as to, or takes any responsibility for, the information relating to the other registrant, except to the extent that such information is included in the portion of this registration statement relating to such registrant.

PROSPECTUS

NORTHWEST NATURAL HOLDING COMPANY

DEBT SECURITIES

JUNIOR SUBORDINATED DEBENTURES

PREFERRED STOCK

COMMON STOCK

Northwest Natural Holding Company (NW Holdings), may offer any combination of the securities described in this prospectus in one or more offerings from time to time and in amounts authorized from time to time. NW Holdings will provide specific terms of its securities, including their offering prices, in supplements to this prospectus. The supplements may also add, update or change information contained in this prospectus. You should read this prospectus and any supplements carefully before you invest.

NW Holdings’ common stock is listed on the New York Stock Exchange and trades under the symbol “NWN.”

NW Holdings may offer these securities directly or through underwriters, agents or dealers. The supplements to this prospectus will describe the terms of any particular plan of distribution, including any underwriting arrangements. The “Plan of Distribution” section on page 9 of this prospectus also provides more information on this topic.

See the discussion of risk factors on page 3 of this prospectus and in the annual, quarterly and current reports filed with the Securities and Exchange Commission (SEC) under the Securities Exchange Act of 1934, as amended (Exchange Act) by NW Holdings and, prior to October 1, 2018, Northwest Natural Gas Company (NW Natural), which are incorporated by reference into this prospectus, to read about certain factors you should consider before purchasing any of the securities being offered.

NW Holdings’ principal executive offices are located at One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209, and its telephone number is (503) 226-4211.

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

The date of this prospectus is October 2, 2018.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that NW Holdings filed with the SEC, utilizing a “shelf” registration, or continuous offering, process. Under this shelf registration or continuous offering process, NW Holdings, from time to time, may sell any combination of the securities described in this prospectus in one or more offerings. NW Holdings may offer any of the following securities: Debt Securities, Junior Subordinated Debentures, Common Stock or Preferred Stock.

This prospectus provides you with a general description of the securities that NW Holdings may offer. Each time NW Holdings sells securities, it will provide a prospectus supplement that will contain specific information about the terms of that offering. Material United States federal income tax considerations applicable to the offered securities will be discussed in the applicable prospectus supplement, if necessary. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described under the heading “Where You Can Find More Information.”

For more detailed information about the securities, you can read the exhibits to the registration statement. Those exhibits have been either filed with the registration statement or incorporated by reference to earlier SEC filings listed in the registration statement.

WHERE YOU CAN FIND MORE INFORMATION

NW Holdings and NW Natural, our predecessor for reporting purposes prior to the completion of the holding company reorganization on October 1, 2018, which is more fully described in the Current Report on Form 8-K filed by NW Holdings and NW Natural on October 1, 2018 that is incorporated herein by reference, file annual, quarterly and other reports and other information with the SEC. Reports, proxy statements and other information filed by NW Holdings or NW Natural can be read and copied at the public reference room of the SEC, 100 F Street, N.E., Washington, D.C. 20549. You can obtain additional information about the Public Reference Room by calling the SEC at 1-800-SEC-0330.

In addition, the SEC maintains a Web site (http://www.sec.gov) that contains reports, proxy statements and other information filed electronically by NW Holdings or NW Natural. NW Holdings also maintains a Web site (http://www.nwnatural.com). Information contained on NW Holdings’ Web site does not constitute part of this prospectus and is not incorporated by reference into this prospectus. The reference to NW Holdings’ Web site is intended to be an inactive textual reference only.

The SEC allows NW Holdings to “incorporate by reference” the information that NW Holdings files (or NW Natural filed prior to October 1, 2018) with the SEC, which means that NW Holdings may, in this prospectus, disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus. NW Holdings is incorporating by reference the documents listed below (other than any portions of such documents that are deemed to be furnished and not filed) and any future filings NW Holdings makes with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, until NW Holdings sells all of the securities described in this prospectus or the offering that this prospectus relates to is terminated. Information that NW Holdings files in the future with the SEC will automatically update and supersede this information.

We hereby incorporate by reference into this prospectus the following documents that we or NW Natural have filed with the SEC:

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You may request a copy of these documents, at no cost to you, by writing or calling Shareholder Services, Northwest Natural Holding Company, One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209, telephone 503-226-4211, extension 2402.

You should rely only on the information contained, or incorporated by reference, in this prospectus and any prospectus supplement. NW Holdings has not, and any underwriters, agents or dealers have not, authorized anyone else to provide you with different information. NW Holdings is not, and any underwriters, agents or dealers are not, making an offer of these securities or soliciting offers to buy these securities in any jurisdiction where the offer or solicitation is not permitted. You should not assume that the information contained in this prospectus and any prospectus supplement is accurate as of any date other than the date on the front of such document or that the information incorporated by reference in this prospectus or any prospectus supplement is accurate as of any date other than the date of the document incorporated by reference.

FORWARD-LOOKING STATEMENTS

This prospectus does, and the documents incorporated herein by reference may, contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (Securities Act), and Section 21E of the Exchange Act. Although NW Holdings believes these statements are based on reasonable assumptions, no assurance can be given that actual results will not differ from those in the forward-looking statements contained herein and in the incorporated documents. The forward-looking statements contained herein and in the incorporated documents may be affected by various uncertainties. For a further discussion of forward-looking statements and of factors which may affect forward-looking statements contained herein and in the incorporated documents, see our most recent Annual Report on Form 10-K and any of our Quarterly Reports on Form 10-Q or Current Reports on Form 8-K filed after that Annual Report on Form 10-K, or, prior to the filing of our Annual Report on Form 10-K for the year ended December 31, 2018, NW Natural’s Annual Report on Form 10-K, its Quarterly Reports on Form 10-Q and its Current Reports on Form 8-K listed above, as well as other filings made with the SEC that are incorporated by reference into this prospectus.

NW HOLDINGS

NW Holdings is a utility holding company primarily engaged, through its wholly-owned subsidiary NW Natural, in the distribution of natural gas. Each of NW Holdings’ subsidiaries is a separate legal entity with its own assets and liabilities. NW Holdings’ executive offices are located at One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209. Its telephone number is 503-226-4211.

NW Natural is principally engaged in the distribution of natural gas in Oregon and southwest Washington. NW Natural and its predecessors have supplied gas service to the public since 1859.

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RISK FACTORS

Investing in the securities involves certain risks. You are urged to read and consider the risk factors described in the annual, quarterly and current reports filed with the SEC under the Exchange Act which are incorporated by reference into this prospectus. Before making an investment decision, you should carefully consider these risks as well as other information NW Holdings includes or incorporates by reference into this prospectus. You should also be aware that new risks may emerge in the future at any time, and NW Holdings cannot predict such risks or estimate the extent to which they may affect NW Holdings’ financial condition or performance. The prospectus supplement applicable to each type or series of securities NW Holdings offers may contain a discussion of additional risks applicable to an investment in NW Holdings and the particular type of securities NW Holdings is offering under that prospectus supplement.

USE OF PROCEEDS

Unless otherwise stated in a prospectus supplement, the net proceeds to be received by NW Holdings from the sale of these securities will be added to the general funds of NW Holdings and used for general corporate purposes.

The prospectus supplement relating to a particular offering of securities will identify the use of proceeds for that offering.

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RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO

COMBINED FIXED CHARGES AND PREFERENCE DIVIDENDS

The ratios of earnings to fixed charges and the ratios of earnings to combined fixed charges and preference dividends, calculated according to the rules set forth under the Securities Act, for the following periods were:

Earnings consist of net income from continuing operations to which has been added taxes on income from continuing operations and fixed charges. Fixed charges consist of interest on all indebtedness, amortization of debt expense and discount or premium, and the estimated interest portion of rentals charged to income. Preference dividends are the amounts of pre-tax earnings from continuing operations that would be required to pay dividends on any outstanding preference equity securities (which could include any NW Holdings preferred stock outstanding for the period).

DESCRIPTION OF DEBT SECURITIES

NW Holdings may issue debt securities, in one or more series, under an indenture, between NW Holdings and the trustee specified therein. The terms of any debt securities will be described in a prospectus supplement.

DESCRIPTION OF JUNIOR SUBORDINATED DEBENTURES

NW Holdings may issue junior subordinated debentures, in one or more series, under an indenture, between NW Holdings and the trustee specified therein. The terms of any junior subordinated debentures will be described in a prospectus supplement.

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DESCRIPTION OF PREFERRED STOCK

General

The following is a summary of certain rights and privileges of NW Holdings’ preferred stock, none of which is currently outstanding. This summary description does not purport to be complete. Reference is made to the laws of the State of Oregon, NW Holdings’ Amended and Restated Articles of Incorporation, Amended and Restated Bylaws, and any articles of amendment to the Amended and Restated Articles of Incorporation establishing a particular series of preferred stock that are filed with the SEC and incorporated herein by reference. The following statements are qualified in their entirety by such references.

The Board of Directors is authorized under NW Holdings’ Amended and Restated Articles of Incorporation to provide for the issuance from time to time of preferred stock in one or more series, and as to each series to fix and determine the relative rights and preferences, serial designation, dividend rate, redemption prices, voluntary and involuntary liquidation prices, sinking fund provisions for the redemption or purchase of shares, if any, and conversion provisions, if any, applicable to shares of such series. NW Holdings will include some or all of this information about a specific series of preferred stock being offered under this prospectus in the prospectus supplement(s) relating to such series. As used herein, the term “preferred stock” includes all series.

Under NW Holdings’ Amended and Restated Articles of Incorporation, NW Holdings is authorized to issue 100,000,000 shares of common stock and 3,500,000 shares of preferred stock. At October 1, 2018, 28,844,190 shares of common stock were outstanding and no shares of preferred stock were outstanding.

Dividends

Each series of the preferred stock shall be entitled, in preference to the common stock, to dividends cumulative from the date of issue, at the rate fixed by the Board of Directors, payable quarterly on February 15, May 15, August 15 and November 15 in each year or on such other date or dates as the Board of Directors shall determine.

Voting Rights

Generally, only NW Holdings’ common stock has voting rights. The common stock has cumulative voting rights with respect to the election of directors. The preferred stock shall have no right to vote in the election of directors or for any other purpose, except as may be otherwise provided by law or by resolutions establishing any series of preferred stock in accordance with NW Holdings’ Amended and Restated Articles of Incorporation.

Certain terms relating to NW Holdings’ preferred stock in respect of dividends, liquidation rights, limitations on payment of dividends and voting are discussed below in “Description of Common Stock—Dividends and Liquidation Rights” and “—Dividend Limitations”.

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DESCRIPTION OF COMMON STOCK

General

The following is a summary of certain rights and privileges of NW Holdings’ common stock. This summary description does not purport to be complete. Reference is made to the laws of the State of Oregon, NW Holdings’ Amended and Restated Articles of Incorporation, and Amended and Restated Bylaws, which are incorporated herein by reference. The following statements are qualified in their entirety by such references.

Under NW Holdings’ Amended and Restated Articles of Incorporation, NW Holdings is authorized to issue 100,000,000 shares of common stock and 3,500,000 shares of preferred stock. At October 1, 2018, 28,844,190 shares of common stock were outstanding and no shares of preferred stock were outstanding.

Dividends and Liquidation Rights

Except as hereinafter stated, the common stock is entitled to receive such dividends as are declared by the Board of Directors and to receive ratably on liquidation any assets which remain after payment of liabilities. NW Holdings has an authorized class of senior capital stock, referred to as preferred stock, none of which is currently outstanding. NW Holdings’ preferred stock is entitled, in preference to the common stock, (1) to cumulative dividends at the annual rate fixed for each series by the Board of Directors, and (2) in voluntary and involuntary liquidation, to the amounts fixed for each series by the Board of Directors, plus in each case, unpaid accumulated dividends.

Dividend Limitations

Should dividends on the preferred stock be in arrears, no dividends on the common stock may be paid or declared. Future series of the preferred stock could contain sinking fund, purchase or redemption obligations under which no dividends on the common stock may be paid or declared while such obligations are in default. Common stock dividends also may be restricted by the provisions of future instruments pursuant to which NW Holdings may issue long-term debt.

Voting Rights

Except as provided by law or by resolutions establishing any series of preferred stock, only the common stock has voting rights. Cumulative voting is permitted by the Amended and Restated Articles of Incorporation to holders of common stock at elections of directors.

Classification of the Board of Directors

The Board of Directors of NW Holdings may consist of not less than nine nor more than thirteen persons, as determined by the Board, divided into three classes as nearly equal in number as possible. The number of directors as of the date of this prospectus is eleven. One class is elected for a three-year term at each annual meeting of shareholders. Vacancies, including those resulting from an increase in the size of the Board, may be filled by a majority vote of the directors then in office, to serve until the next annual meeting of shareholders. One or more of the directors may be removed, with or without cause, by the affirmative vote of the holders of not less than two-thirds of the shares entitled to vote thereon; provided, however, that if fewer than all of the directors should be candidates for removal, no one of them shall be removed if the votes cast against such director’s removal would be sufficient to elect such director if then cumulatively voted at an election of the class of directors of which such director shall be a part. Except for those persons nominated by the Board, no person shall be eligible for election as a director unless a request from a shareholder entitled to vote in the election of directors that such person be nominated and such person’s consent thereto shall be delivered to the Secretary of NW Holdings within the time period specified in advance of the meeting at which such election shall be held. The foregoing provisions may not be amended or repealed except by the affirmative vote of the holders of not less than two-thirds of the shares entitled to vote at an election of directors.

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Business Transactions with Related Persons

NW Holdings shall not enter into any business transaction with a related person or in which a related person shall have an interest (except proportionately as a shareholder of NW Holdings) without first obtaining both (1) the affirmative vote of the holders of not less than two-thirds of the outstanding shares of the capital stock of NW Holdings not held by such related person, and (2) the determination of a majority of the continuing directors that the cash or fair market value of the property, securities or other consideration to be received per share by the holders, other than such related person, of the shares of each class or series of the capital stock of NW Holdings in such business transaction shall not be less than the highest purchase price paid by such related person in acquiring any of its holdings of shares of the same class or series, unless the continuing directors by a majority vote shall either (a) have expressly approved the acquisition of the shares of the capital stock of NW Holdings that caused such related person to become a related person, or (b) have expressly approved such business transaction. As used in this paragraph: a “business transaction” includes a merger, consolidation, plan of exchange or recapitalization, a purchase, sale, lease, exchange, transfer, mortgage or other disposition of all or a substantial part (10% or more of the fair market value of the assets) of the property and assets of NW Holdings or a related person, an issuance, sale, exchange or other disposition of securities of NW Holdings and a liquidation, spin-off or dissolution; a “related person” includes a person, organization or group thereof owning 10% or more of the capital stock of NW Holdings; “continuing directors” are those directors who were directors of NW Holdings on the date the Amended and Restated Articles of Incorporation first became effective or whose nominations have been approved by a majority of the then continuing directors. The foregoing provisions may not be amended or repealed except by the affirmative vote of the holders of not less than two-thirds of the shares of the capital stock of NW Holdings (other than shares held by related persons).

Preemptive Rights

The holders of the common stock have no preemptive rights.

Certain Anti-Takeover Matters

NW Holdings’ Amended and Restated Articles of Incorporation and Amended and Restated Bylaws include a number of provisions that may have the effect of discouraging persons from acquiring large blocks of its stock or delaying or preventing a change in its control. The material provisions that may have such an effect include:

NW Holdings is subject to the provisions of sections 60.825 to 60.845 of the Oregon Business Corporation Act (Oregon Business Combinations Act) which generally provide that in the event a person or entity acquires 15% or more of NW Holdings’ voting stock (Interested Shareholder), NW Holdings and such Interested Shareholder and any affiliate may not engage in the following business combinations for a period of three years following the date that person became an Interested Shareholder:

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These restrictions do not apply if:

NW Holdings is also subject to the provisions of Sections 60.801 to 60.816 of the Oregon Business Corporation Act (Oregon Control Share Act), which generally provide that a person who acquires voting stock in a transaction which results in such person holding more than 20%, 33-1/3% or 50% of the total voting power cannot vote the shares it acquires in the acquisition unless voting rights are accorded to such control shares by the holders of a majority of the outstanding voting shares, excluding the control shares held by such person and shares held by officers and inside directors, and by the holders of a majority of the outstanding voting shares, including the control shares held by such person and shares held by officers and inside directors. This vote would be required at the time an acquiring person’s holdings exceed 20% of the total voting power, and again at the time the acquiring person’s holdings exceed 33-1/3% and 50%, respectively. The acquiring person may, but is not required to, submit to NW Holdings an “acquiring person statement” setting forth certain information about the acquiring person and its plans with respect to NW Holdings. The acquiring person statement may also request that NW Holdings call a special meeting of shareholders to determine whether the control shares will be allowed to retain voting rights. If the acquiring person does not request a special meeting of shareholders, the issue of voting rights of control shares will be considered at the next annual meeting or special meeting of shareholders that is held more than 60 days after the date of the acquisition of control shares. Shares are not deemed to be acquired in a control share acquisition if, among other things, they are acquired from the issuing corporation, or are issued pursuant to a plan of merger or exchange effected in compliance with the Oregon Business Corporation Act and the issuing corporation is a party to the merger or exchange agreement.

The Oregon Control Share Act and the Oregon Business Combinations Act have anti-takeover effects because they will encourage any potential acquirer to negotiate with NW Holdings’ Board of Directors and will also discourage potential acquirers unwilling to comply with the provisions of these laws. An Oregon corporation may provide in its articles of incorporation or bylaws that the laws described above do not apply to its shares. NW Holdings has not adopted such a provision.

NW Holdings is also subject to Oregon Revised Statutes Chapter 757.511 which generally provides that no person, directly or indirectly, shall acquire the power to exercise any substantial influence over the policies and actions of a public utility without first securing from the Oregon Public Utility Commission (OPUC) an order authorizing such acquisition if such person is, or by such acquisition would become, an “affiliated interest” with such public utility as defined by Oregon law. Any applicant requesting such an order bears the burden of showing that granting the application is in the public interest. This provision of Oregon law may have anti-takeover effects by subjecting potential acquisitions to OPUC review and approval.

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PLAN OF DISTRIBUTION

NW Holdings may sell the securities offered pursuant to this prospectus and one or more prospectus supplements (Offered Securities), on a continuous or delayed basis, in one or more series: (1) through one or more underwriters or dealers; (2) through one or more agents; (3) directly to a single purchaser or a limited number of purchasers; (4) through a combination of any such methods of sale; or (5) through other methods described in the applicable prospectus supplement.

Through Underwriters or Dealers

If underwriters are used in the sale, the Offered Securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, at the initial public offering price or at varying prices determined at the time of the sale. The Offered Securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more managing underwriters. The underwriter or underwriters with respect to the Offered Securities will be named in the prospectus supplement relating to such offering and, if an underwriting syndicate is used, the managing underwriter or underwriters will be set forth on the cover page of such prospectus supplement. Unless otherwise set forth in such prospectus supplement, the obligations of the underwriters to purchase the Offered Securities offered by such prospectus supplement will be subject to certain conditions precedent, and the underwriters will be obligated to purchase all of such Offered Securities if any are purchased. If a dealer is used in the sale, the securities will be sold to the dealer as principal. The dealer may then resell those securities at varying prices determined at the time of resale.

Through Agents

The Offered Securities may be sold through agents designated by NW Holdings from time to time. A prospectus supplement will set forth the name of any agent involved in the offer or sale of the Offered Securities in respect of which such prospectus supplement is delivered as well as any commissions payable by NW Holdings to such agent. Unless otherwise indicated in such prospectus supplement, any such agent will be acting on a reasonable best efforts basis to solicit purchases for the period of its appointment.

Directly to One or More Purchasers

NW Holdings may sell the Offered Securities directly to one or more purchasers. In this case, no underwriters or agents would be involved.

General Information

The prospectus supplement with respect to the Offered Securities will set forth the terms of the offering of such Offered Securities, including:

Any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

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If so indicated in the prospectus supplement with respect to the Offered Securities, NW Holdings may authorize agents, underwriters or dealers to solicit offers by certain specified institutions to purchase the Offered Securities from NW Holdings at the initial public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. Such contracts will be subject to those conditions set forth in such prospectus supplement, and such prospectus supplement will set forth the commission payable for solicitation of such contracts.

The securities may also be offered and sold, if so indicated in the applicable prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more firms, which are referred to herein as the “remarketing firms,” acting as principals for their own accounts or as our agent, as applicable. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters, as that term is defined in the Securities Act, in connection with the securities remarketed thereby.

Unless otherwise specified in the applicable prospectus supplement, except for our common stock, which is listed on the New York Stock Exchange, the securities will not be listed on a national securities exchange.

We may enter into derivative transactions with third parties or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of securities, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of securities. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be identified in the applicable prospectus supplement.

We may make sales of our common stock to or through one or more underwriters, dealers or agents in “at the market” offerings, and, if we engage in such transactions, we will do so pursuant to the terms of an agreement between us and the underwriters, dealers or agents. If we engage in at the market sales pursuant to a distribution or similar agreement, we will issue and sell shares of our common stock to or through one or more underwriters or agents, which may act on an agency basis or on a principal basis.

Agents, underwriters and dealers may be entitled under agreements entered into with NW Holdings to indemnification by NW Holdings against certain civil liabilities, including certain liabilities under the Securities Act or to contribution by NW Holdings with respect to payments which such agents, underwriters and dealers may be required to make in respect thereof.

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EXPERTS

The financial statements and management’s assessment of the effectiveness of internal control over financial reporting (which is included in Management’s Report on Internal Control over Financial Reporting) incorporated in this Prospectus by reference to NW Natural’s Current Report on Form 8-K dated September 24, 2018 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

LEGALITY

The legality of the securities will be passed upon for NW Holdings by MardiLyn Saathoff, Esquire, Senior Vice President and General Counsel of NW Holdings, and by Morgan, Lewis & Bockius LLP, New York, New York. Ms. Saathoff may rely upon the opinion of Morgan, Lewis & Bockius LLP as to certain legal matters arising under New York law. Morgan, Lewis & Bockius LLP may rely upon the opinion of Ms. Saathoff as to certain legal matters arising under Oregon law. Ms. Saathoff is regularly employed by NW Holdings, participates in various NW Holdings employee benefit plans under which she may receive shares of common stock and currently beneficially owns less than one percent of the outstanding shares of common stock of NW Holdings.

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PROSPECTUS

NORTHWEST NATURAL HOLDING COMPANY

DIVIDEND REINVESTMENT AND

DIRECT STOCK PURCHASE PLAN

COMMON STOCK

Northwest Natural Holding Company (NW Holdings) has established its Dividend Reinvestment and Direct Stock Purchase Plan (Plan) to provide participants with a convenient way to purchase shares of common stock and reinvest all or a portion of the cash dividends paid on common stock in additional shares of NW Holdings’ common stock.

Participants in the Plan may:

Shares purchased under the Plan will, at NW Holdings’ option, be (i) authorized but unissued shares purchased directly from NW Holdings, (ii) shares purchased in the open market or in privately negotiated transactions, or (iii) any combination of the foregoing. Any open market or privately negotiated purchases will be made through an independent agent. This prospectus relates to the offer and sale of up to 406,749 shares of common stock offered under the Plan.

Investors currently participating in the Plan will remain enrolled in the Plan and do not have to take any action unless they wish to terminate participation or change an election in the Plan.

NW Holdings’ common stock is listed on the New York Stock Exchange and trades under the ticker symbol “NWN.”

To the extent required by applicable law in certain jurisdictions, shares of common stock offered under the Plan to certain persons are offered only through a registered broker/dealer in such jurisdictions.

See the discussion of risk factors on page 3 of this prospectus and in the annual, quarterly and current reports filed with the Securities and Exchange Commission (SEC) under the Securities Exchange Act of 1934, as amended (Exchange Act) by NW Holdings and, prior to October 1, 2018, Northwest Natural Gas Company (NW Natural), which are incorporated by reference into this prospectus, to read about certain factors you should consider before purchasing any of the securities being offered.

NW Holdings’ principal executive offices are located at One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209, and its telephone number is (503) 226-4211.

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

The date of this prospectus is October 2, 2018.

TABLE OF CONTENTS

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WHERE YOU CAN FIND MORE INFORMATION

NW Holdings and NW Natural, our predecessor for reporting purposes prior to the completion of the holding company reorganization on October 1, 2018, which is more fully described in the Current Report on Form 8-K filed by NW Holdings and NW Natural on October 1, 2018 that is incorporated herein by reference, file annual, quarterly and other reports and other information with the SEC. Reports, proxy statements and other information filed by NW Holdings or NW Natural can be read and copied at the public reference room of the SEC, 100 F Street, N.E., Washington, D.C. 20549. You can obtain additional information about the Public Reference Room by calling the SEC at 1-800-SEC-0330.

In addition, the SEC maintains a Web site (http://www.sec.gov) that contains reports, proxy statements and other information filed electronically by NW Holdings or NW Natural. NW Holdings also maintains a Web site (http://www.nwnatural.com). Information contained on NW Holdings’ Web site does not constitute part of this prospectus and is not incorporated by reference into this prospectus. The reference to NW Holdings’ Web site is intended to be an inactive textual reference only.

The SEC allows NW Holdings to “incorporate by reference” the information that NW Holdings files (or NW Natural filed prior to October 1, 2018) with the SEC, which means that NW Holdings may, in this prospectus, disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus. NW Holdings is incorporating by reference the documents listed below (other than any portions of such documents that are deemed to be furnished and not filed) and any future filings NW Holdings makes with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, until NW Holdings sells all of the securities described in this prospectus or the offering that this prospectus relates to is terminated. Information that NW Holdings files in the future with the SEC will automatically update and supersede this information.

We hereby incorporate by reference into this prospectus the following documents that we or NW Natural have filed with the SEC:

You may request a copy of these documents, at no cost to you, by writing or calling Shareholder Services, Northwest Natural Holding Company, One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209, telephone 503-226-4211, extension 2402.

You should rely only on the information contained, or incorporated by reference, in this prospectus and any prospectus supplement. NW Holdings has not, and any underwriters, agents or dealers have not, authorized anyone else to provide you with different information. NW Holdings is not, and any underwriters, agents or dealers are not, making an offer of these securities or soliciting offers to buy these securities in any jurisdiction where the offer or solicitation is not permitted. You should not assume that the information contained in this prospectus and any prospectus supplement is accurate as of any date other than the date on the front of such document or that the information incorporated by reference in this prospectus or any prospectus supplement is accurate as of any date other than the date of the document incorporated by reference.

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FORWARD-LOOKING STATEMENTS

This prospectus does, and the documents incorporated herein by reference may, contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (Securities Act), and Section 21E of the Exchange Act. Although NW Holdings believes these statements are based on reasonable assumptions, no assurance can be given that actual results will not differ from those in the forward-looking statements contained herein and in the incorporated documents. The forward-looking statements contained herein and in the incorporated documents may be affected by various uncertainties. For a further discussion of forward-looking statements and of factors which may affect forward-looking statements contained herein and in the incorporated documents, see our most recent Annual Report on Form 10-K and any of our Quarterly Reports on Form 10-Q or Current Reports on Form 8-K filed after that Annual Report on Form 10-K, or, prior to the filing of our Annual Report on Form 10-K for the year ended December 31, 2018, NW Natural’s Annual Report on Form 10-K, its Quarterly Reports on Form 10-Q and its Current Reports on Form 8-K listed above, as well as other filings made with the SEC that are incorporated by reference into this prospectus.

NW HOLDINGS

NW Holdings is a utility holding company primarily engaged, through its wholly-owned subsidiary NW Natural, in the distribution of natural gas. Each of NW Holdings’ subsidiaries is a separate legal entity with its own assets and liabilities. NW Holdings’ executive offices are located at One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209. Its telephone number is 503-226-4211.

NW Natural is principally engaged in the distribution of natural gas in Oregon and southwest Washington. NW Natural and its predecessors have supplied gas service to the public since 1859.

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RISK FACTORS

Investing in the common stock involves certain risks. You are urged to read and consider the risk factors described in the annual, quarterly and current reports filed with the SEC under the Exchange Act which are incorporated by reference into this prospectus. Before making an investment decision, you should carefully consider these risks as well as other information NW Holdings includes or incorporates by reference into this prospectus. You should also be aware that new risks may emerge in the future at any time, and NW Holdings cannot predict such risks or estimate the extent to which they may affect NW Holdings’ financial condition or performance.

You should also consider specific risk factors such as:

The price of NW Holdings’ common stock may rise during the period between making an optional cash payment, receipt of the payment by the Plan administrator and the actual purchase of the stock.

Participants in the Plan have no control over or authority to direct the timing or price at which shares of common stock are purchased for their accounts. You bear this risk by participating in the Plan. You will not earn interest on funds held by the Plan administrator pending their investment in common stock.

The price of NW Holdings common stock may fall during the period between a request for sale, receipt of the request by the Plan administrator and the sale in the open market.

Participants should be aware that the price of NW Holdings common stock may fall during the period between a request for sale, receipt of the request by the Plan administrator and the sale of the stock in the open market. You bear this risk by participating in the Plan. Therefore, you should evaluate this possibility when deciding whether and when to sell any shares through the Plan.

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THE PLAN

DESCRIPTION OF THE PLAN

The provisions of the Plan in effect on and after the date hereof are presented in the following questions and answers.

Purpose

The Plan provides interested investors with a convenient method of purchasing NW Holdings’ common stock directly through the Plan administrator (the Agent, as defined in Question 5), and provides current shareholders with a convenient method of investing cash dividends on their NW Holdings shares in additional shares of common stock. At NW Holdings’ option, shares purchased under the Plan will be (a) authorized but unissued shares purchased directly from NW Holdings, (b) shares purchased in the open market or in privately negotiated transactions, or (c) any combination of the foregoing. When shares purchased under the Plan are acquired directly from NW Holdings, NW Holdings will receive additional equity funds which will be added to its general funds and used for general corporate purposes as described in “Use of Proceeds.”

Advantages

Disadvantages

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Therefore, the participant will bear the risk of fluctuations in the market price of NW Holdings’ common stock. See “Risk Factors.”

Other Features

Administration

By participating in the Plan, each participant designates American Stock Transfer & Trust Company, LLC (AST) (or a successor thereto) as his or her agent under the Plan (Agent). The Agent will administer the Plan, receive and hold participants’ funds pending investment in additional shares of common stock, effect transfers of common stock, keep a continuous record of participation and prepare and send to each participant statements of the participant’s Plan account. Shares purchased under the Plan will be registered in the name of the Agent (or its nominee) and held by the Agent for each participant in the Plan. In the event that AST ceases to act as the Plan administrator, NW Holdings will appoint a new Plan administrator to act as Agent and administer the Plan.

The Agent will use a broker-dealer registered under the Exchange Act (Purchasing Representative) to act as an independent agent on behalf of Plan participants in purchasing and selling shares for participants in the open market or in privately negotiated transactions. Subject to the objective of obtaining the lowest over-all costs of shares purchased, the Purchasing Representative will have full discretion as to all matters relating to purchases of shares.

The law in some jurisdictions requires NW Holdings to offer shares through this Plan only through a registered broker/dealer. In those instances, the Purchasing Representative will also act as the registered broker/dealer.

NW Holdings reserves the right to interpret and administer the Plan as deemed necessary or desirable, including the right to limit or deny participation in the Plan where circumstances warrant. The terms and conditions of the Plan and its operation shall be governed by and construed in accordance with the laws of the State of Oregon. None of NW Holdings, AST, or its Purchasing Representative will be liable for any act done in good faith or for any omission to act in good faith, provided that NW Holdings shall not be relieved from any liability imposed under any federal, state or other applicable securities law which cannot be waived. You should recognize that NW Holdings cannot assure you of a profit or protect you against a loss on shares purchased or sold under the Plan. A participant participates in the Plan at his or her sole discretion, risk and responsibility. See “Risk Factors.”

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Participants may contact the Agent:

Existing shareholders may log into their accounts at www.astfinancial.com by clicking on “Shareholder Central” and following the instructions.

Non-shareholders may enroll in and purchase shares under the Plan at www.astfinancial.com by clicking on “Invest Online” and following the instructions.

The Board of Directors of NW Holdings reserves the right to amend, suspend, modify or terminate the Plan at any time, including, but not limited to, the right to modify the fees and commissions charged to participants. Notice of any such amendment, suspension, major modification or termination of the Plan would be provided to all participants. Upon termination of the Plan, the Agent will send you a certificate or a statement evidencing electronically issued shares credited to your account for whole Plan Shares held in your account at the time of termination and a check for the cash value of any fractional Plan Shares held at such time.

Eligibility

The Plan is available to any person of legal age or entity, whether or not a holder of NW Holdings’ common stock, provided that such person or entity fulfills the prerequisites for participation described under Question 9 and participation would not violate the securities or other laws of the state, territory or country where the participant resides that are applicable to NW Holdings, the Plan or the participant. Shares for which dividends are reinvested by the Plan must be Registered Shares or Plan Shares. Beneficial owners of NW Holdings common stock are owners whose shares are held in a brokerage account by a bank, broker or other custodial institution in “street name.” In order to participate in the Plan, such beneficial owners must request the bank, broker or other custodial institution to have such shares registered in the owner’s name. Alternatively, such beneficial owners may participate in the Plan indirectly by requesting the bank, broker or custodial institution to participate on the owner’s behalf.

In certain jurisdictions, applicable laws require NW Holdings to use a registered broker-dealer to offer common stock under the Plan to persons not presently shareholders of record. No offers or sales will be effected in those jurisdictions unless NW Holdings has satisfied the requirements of the state securities laws applicable to the operation of the Plan. To the extent required by applicable law in certain jurisdictions, NW Holdings will offer shares of common stock under the Plan to persons not presently shareholders of record of common stock

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only through a registered broker/dealer in those jurisdictions. The Agent will select a registered broker/dealer through whom NW Holdings will offer shares in those instances and for all Plan trading activity.

A Plan prospectus and enrollment or application information will be furnished upon request made to the Agent or it may be obtained from the Agent’s website at http://www.astfinancial.com.

Participation

Current participants will automatically be participants in the Plan as amended to date, and need do nothing to continue their participation.

After receiving a copy of this prospectus, shareholders may become participants in the Plan by completing and signing an enrollment form (Enrollment Form) and non-shareholders may become participants by completing and signing an application (Application).

An Enrollment Form or Application may be obtained by contacting the Agent at 1-888-777-0321 or by visiting their website at www.astfinancial.com and downloading the forms.

The Enrollment Form and Application require a participant to choose a reinvestment option for participation in the Plan. By checking the appropriate box a participant may select:

Under any of the investment options, a participant may make optional cash investments of a minimum of $50 (or a minimum of $250 for the initial investment by a non-shareholder) and a maximum of $250,000 per calendar year (including the initial investment) towards the purchase of additional shares of common stock, which maximum amount may be waived at our discretion.

If participants do not indicate an investment option on the enrollment form, their account will automatically be enrolled in the “Full Dividend Reinvestment” option.

Participants may change their reinvestment options by completing the tear-off portion of their Investment Statement of account or an enrollment form and sending it to the Agent. Changes will become effective as soon as practicable after they are received. Any change in reinvestment options must be received by the dividend record date (see Question 10, below) in order to be effective on the related payment date.

Dividend Reinvestment

Each cash dividend payment date on the common stock will be an Investment Date under the Plan; which means that, for participants who choose to reinvest dividends, the dividend payments on such payment date will be used to purchase additional shares of common stock as of such payment date. Common stock cash dividend payment dates are specified by the Board and are ordinarily on or about the fifteenth day of February, May, August and November and corresponding record dates normally precede payment dates by approximately 15 days.

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If NW Holdings is meeting the requirements of the Plan with common stock purchased in the open market or in privately negotiated transactions, the Purchasing Representative will determine the exact timing of such purchases and the number of shares to be purchased, depending on the amount of reinvested dividends, market conditions and the requirements of federal securities laws, and the purchased shares will be credited to a participant’s Plan account as of the applicable Investment Date. If NW Holdings elects to issue authorized but unissued shares of common stock directly to the Agent, these shares will be issued by NW Holdings and credited to a participant’s Plan account as of the applicable Investment Date. The determination of the price for purchases of Plan Shares is explained in Question 17. In any case, dividends not invested in shares of common stock within 30 days of the dividend payment date will be returned, without interest, to the participant.

If a participant’s Enrollment Form is received by the Agent on or before the record date for a dividend payment, the dividend payable on such Investment Date will be used to purchase additional shares of common stock as of such Investment Date, unless the Enrollment Form indicates “Full Cash Payments Only.” If the Enrollment Form is received after the record date for any such cash dividend payment date, the reinvestment of dividends will start with the next dividend payment date. If a certificate representing Registered Shares to be deposited for safekeeping, together with a completed Safekeeping Authorization Instruction form, is received on or before the record date for a dividend payment, reinvestment of dividends on such shares will begin with that dividend. If such certificate and Instruction are received after the record date for a dividend payment, reinvestment of dividends will begin with the next dividend payment date unless a participant already has elected “Full Dividend Reinvestment” for such shares.

For example, a dividend payable February 15 will be reinvested if a completed Enrollment Form, or a certificate and a completed Safekeeping Authorization Instruction form, is received by the Agent on or before the record date of January 31. If the Enrollment Form, or such certificate and Instruction, is received after January 31, but on or before the record date for the next dividend payment, the first dividend reinvested will be the dividend payable May 15.

Optional Cash Payments

All Plan participants, whether or not they have authorized the reinvestment of dividends, are eligible to make optional cash payments.

A Plan participant may make an initial cash investment when enrolling by enclosing a check with the Enrollment Form or Application. Checks should be made payable to “American Stock Transfer & Trust Co., LLC” and returned to the address specified or in the envelope provided. Thereafter, optional cash payments may be made by using the cash payment form attached to the statement of account, or through the Automatic Monthly Deduction Form (see Question 13). If a participant uses the cash payment form, the same amount of money need not be sent each month and there is no obligation to make an optional cash purchase each month. Participants may also elect to make optional cash payments by accessing their participant accounts at www.astfinancial.com.

The Plan offers a program which allows participants to make optional cash purchases by authorizing automatic payments from bank accounts designated by the participants. Payments made through this method, which must be the same amount each month as designated by the participant, are deducted on or about the 10th of each month and are invested on or about the 15th of each month. For an Automatic Monthly Deduction Form, please contact the Agent.

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There is a $50 minimum amount required for optional cash payments by shareholders, except as provided in Question 20. In case of an initial optional cash payment by a non-shareholder, such optional cash payments cannot be less than $250. The maximum aggregate optional cash payment that may be made by a participant in any calendar year cannot exceed $250,000, which maximum amount may be waived at our discretion.

Investment Dates for optional cash payments will occur monthly, usually on or about the 15th day of each month. Purchases may be made over a period of several days in the case of market purchases. All such purchases will be aggregated and credited to participants’ accounts on the Investment Date occurring on or after receipt of the optional cash payment.

The Agent must receive optional cash payments at least three business days prior to an Investment Date to be invested on that Investment Date. Otherwise, the Agent will hold the optional cash payments for investment until the next Investment Date. Optional cash payments which remain uninvested more than 35 days following receipt by the Agent will be returned, without interest, to the participant. Optional cash payments received by the Agent will be returned to the participants upon written request received by the Agent at least three business days prior to the Investment Date following their receipt. No interest will be paid by NW Holdings or the Agent on any cash investments received by the Agent pending investment.

Purchases

The number of shares to be purchased under a Plan depends on the amount of a participant’s funds available for investment and the price of the shares. The funds available for investment depend on what has been authorized in regard to dividend reinvestment, plus any optional cash payments made. In every case, available funds will be fully invested in both whole and fractional shares of common stock (computed to three decimal places). No one can predict the number of shares that will be purchased for Plan participants during a particular purchase period, and Plan participants cannot direct the purchase of a specific number of shares.

If the Agent purchases authorized but unissued shares of common stock directly from NW Holdings, the price of such shares will be the average of the high and low sales prices of NW Holdings’ common stock on the trading day preceding the applicable Investment Date reported on the consolidated tape for the NYSE listed companies administered by the Consolidated Tape Association.

The purchase price of shares purchased in respect of any Investment Date on the NYSE or through privately negotiated transactions will be the average price (including brokerage fees) paid by the Purchasing Representative to obtain such shares.

The Purchasing Representative may offset purchases of shares against sales of shares to be made for participants under the Plan with respect to an Investment Date, resulting in a net purchase or a net sale of shares.

NW Holdings, at its discretion, may elect to satisfy the requirements of the Plan with either (i) authorized but unissued shares of common stock, (ii) shares of common stock purchased in the open market or in privately negotiated transactions, or (iii) any combination of the foregoing. If NW Holdings elects to purchase shares of common stock in the open market or in privately negotiated transactions, the Purchasing Representative will make all such purchases necessary to meet the requirements of the Plan. Shares purchased in any month on the

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NYSE or through privately negotiated transactions will be purchased, at the discretion of the Purchasing Representative, during the period beginning on the third trading day prior to the Investment Date for that month and typically ending by the fifth trading day after the Investment Date. Other than establishing the length of any such investment period incorporated into the Plan, NW Holdings does not exercise any direct or indirect control over the timing or price of purchases made by the Purchasing Representative.

NW Holdings cannot change its determination that shares will be purchased on the open market or in privately negotiated transactions or directly from NW Holdings more frequently than once every three months.

In most cases, NW Holdings will pay the fees and expenses to operate the Plan. However, there are some service fees and brokerage commissions which will be charged directly to participants. Participants will incur no broker fees, commissions or other charges for authorized but unissued shares purchased directly from NW Holdings. Participants in the Plan will bear the cost of brokerage fees and commissions, any service charges and applicable taxes related to shares purchased or sold on the open market or in privately negotiated transactions.

A service fee of up to $30 will be assessed for each item that is returned for insufficient funds. The Agent may place a hold on the account until the “insufficient funds” fee is received, sell shares from the account to collect the “insufficient funds” fee, or withhold the amount of the “insufficient funds” fee from future optional cash investments.

See Question 24 for fees associated with Safekeeping and Question 20 for service fees associated with the sale of shares.

NW Holdings reserves the right at any time to change fees or to charge participants (including those who do not reinvest dividends) other fees, including but not limited to administrative, setup and handling fees. Notice of such future changes or additional fees will be sent to participants at least 30 days prior to their effective date.

Sales and Termination from the Plan

Yes. Any participant may withdraw from the Plan, request that Plan Shares be moved to NW Holdings’ direct registration system (DRS), request that a certificate be issued for Plan Shares, or request that all or a portion of the whole Plan Shares be sold and that the cash proceeds, less any fees discussed below, be forwarded to the participant. Participation in the Plan is entirely voluntary. In order to withdraw shares from the Plan, a participant must notify the Agent either in writing by using the transaction request form attached to the bottom of the statement or through the website at www.astfinancial.com that the participant wishes to withdraw.

A stock certificate for any whole number of shares may be issued from a Plan account or any whole number of shares can be moved to the DRS as soon as practicable after it is requested by a participant or upon termination of the Plan by NW Holdings. Certificates for whole shares withdrawn from the Plan will be registered under the name in which the participant’s certificates were registered upon entering the Plan. A cash payment will be made for any fraction of a share.

If a termination request does not specify the manner of distribution of shares, the Agent will move the whole number of shares in that account to the DRS and issue a check for the value of any remaining fractional shares. The Agent will only issue certificates for whole shares.

Except as otherwise provided in the following paragraph, any sale of whole shares will be made within two business days after receipt of the request by the Agent. The participant will receive the proceeds of the sale, less a

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service charge of $15, and any applicable brokerage fees or commissions and any withholding required under applicable tax laws, from the sale of the whole shares sold at the participant’s request, and a cash payment for any fraction of a share credited to the participant’s account.

A participant may withdraw from the Plan at any time if notice is received at least three business days prior to a payable date, in such case the dividend will be paid in cash. If a participant’s request is received less than three business days prior to the payable date, then the immediate dividend will be reinvested and all subsequent dividends will be paid in cash.

If a participant disposes of all Registered Shares, NW Holdings, at its option, either may treat such disposal as a notice of withdrawal or may continue to reinvest the dividends on Plan Shares.

Reports to Participants

As soon as practicable after purchases for their accounts, statements will be mailed to participants advising them of their investments. The statements are participants’ continuing record of the cost of their purchases and should be retained for income tax purposes. In addition, participants will receive copies of the same communications sent to every other holder of shares of common stock, including NW Holdings’ annual report, notice of annual meeting and proxy statement, and income tax information form reporting dividends paid.

Certificates for Shares; Direct Registration System

No. Unless requested otherwise as described below or the account is terminated, the number of shares purchased under the Plan and any shares deposited with the Agent for safekeeping will be held by the Agent or its nominee for the participants. At any time, a participant may request the Agent to send him a certificate for any whole shares credited to the participant’s account. Any remaining whole shares and fraction of a share will continue to be credited to the participant’s account. This service protects against loss, theft or destruction of stock certificates.

Certificates for fractional shares will not be issued under any circumstances.

Shares credited to Plan accounts may not be used as collateral. To use Plan shares as collateral, participants must request that a certificate be issued in their name or request the Agent to move the Plan shares to book-entry form under the DRS.

A participant’s Plan account is maintained in the same name in which the participant’s certificates were registered when he or she entered the Plan. If a participant enrolled in the Plan directly, the account is maintained in the name recorded when the participant enrolled.

A participant can request stock certificates or can request to move to the DRS any number of whole shares credited to its Plan account, and may make such request without withdrawing from the Plan. There is no charge for this service. The DRS permits an investor to hold NW Holdings common stock as the registered owner in book-entry registration form on the stock transfer books of NW Holdings, with no need for a physical stock certificate.

A participant must make a written request to the Agent by:

1) completing the transaction request form attached to the bottom of its statement; or

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2) submitting a letter of instruction indicating the Plan account number and registration.

The request should indicate the number of shares to be certificated or moved to DRS and must be signed by all Plan account owners. A participant must make a separate request each time a certificate or movement to DRS is requested. We process requests as soon as practicable after we receive them. We will continue to hold any remaining full and fractional shares in the participant’s Plan account. Fractional shares cannot be issued in certificate form or moved to DRS.

Certificating a participant’s Plan shares or moving them to DRS does not automatically stop dividend reinvestment. We will continue to follow existing instructions regarding payment or reinvestment of dividends on shares moved to certificate form or DRS until we receive new instructions. To make a change in method of dividend payment, a participant must make a request in writing as more fully described under “Dividend Reinvestment”.

Transfer of Shares Held in the Plan

Upon written request, Plan shares can be transferred into names other than the account name, subject to compliance with any applicable laws and the payment by the participant of any applicable taxes, provided that the request is accompanied by a duly executed stock power that bears the signature(s) of the participant(s) and the signature(s) is/are Medallion Guaranteed by a financial institution, such as a commercial bank or a brokerage firm, that is a member of either the STAMP, SEMP or MSP Medallion Guarantee programs. Unless instructed otherwise, the Agent will hold the transferred shares in an account in the transferee’s name in the Plan and apply the same dividend reinvestment options as existed with respect to the transferred account.

Safekeeping Service for Common Stock Certificates

A participant may elect to deposit Registered Shares into his or her Plan account for safekeeping as Plan Shares. Any lost certificates must be replaced before a participant may deposit the shares represented by such certificate. A participant may elect to have cash dividends on shares deposited for safekeeping reinvested under the Plan.

Certificates representing Registered Shares to be deposited for safekeeping should be sent, together with a completed Safekeeping Authorization Instruction form, by registered mail to the Agent. Certificates should not be endorsed. A Safekeeping Authorization Instruction form may be obtained from the Agent at any time. The participant will incur a service fee of $7.50 for the handling of each safekeeping request.

It is suggested that participants use registered mail when sending stock certificates, declaring a value equal to 3% of the market value of the shares on the date of mailing. This amount would be the approximate cost of replacing the certificates should they be lost in the mail.

It is the responsibility of the participant to retain his or her records relative to the cost of any shares represented by certificates deposited for safekeeping.

Minimum Share Ownership

A participant must continue to own at least one share of our common stock or the participant’s account will be closed. Any fractional shares will be liquidated at our expense and the proceeds mailed to the participant at the address on file. At our discretion, we may waive this requirement.

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Other Information

Any dividend payable in stock or split shares distributed by NW Holdings on Plan Shares, both full and fractional, will be credited to the participant’s account. Such stock dividends or split shares distributed on Registered Shares will be mailed directly to the participant in the same manner as to the shareholders who are not participating in the Plan.

Transaction processing may be curtailed or suspended until the completion of any stock dividend, stock split or other corporate action.

Participants will be sent notices of meetings, proxy statements and proxy forms for each meeting of shareholders. Plan Shares, including fractional Plan Shares, will be voted as the participant directs. Registered Shares will be voted directly by the participant.

The proxy card sent to each participant in connection with any annual or special meeting of shareholders will represent all Registered Shares, if any, and all Plan Shares owned by such participant.

As in the case of non-participating shareholders, if no instructions are indicated on the properly signed and returned proxy card, all of the participant’s shares—Registered Shares, if any, and Plan Shares—will be voted as provided on the proxy card. If the proxy card is not returned or if the participant does not grant a proxy by voting by telephone or the Internet, the participant’s shares may be voted only if the participant or a duly appointed representative votes in person at the meeting.

Neither NW Holdings nor the Agent administering the Plan will be liable for any act done in good faith or for any good faith omission to act including, without limitation, any claim of liability arising out of failure to terminate a participant’s account upon such participant’s death or with respect to the prices at which shares of common stock are purchased or sold for the participant’s account and the times when such purchases or sales are made or with respect to any fluctuation in the market value after the purchase or sale of shares.

Participants should recognize that NW Holdings cannot assure a profit or protect against a loss on the shares purchased or sold under the Plan.

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USE OF PROCEEDS

NW Holdings will receive proceeds from the purchase of its common stock pursuant to the Plan only to the extent that those purchases are of newly issued shares of its common stock made directly from NW Holdings, and not from open market purchases. Any proceeds that NW Holdings receives from purchases of newly issued shares will be added to NW Holdings’ general funds and used for general corporate purposes. NW Holdings cannot estimate the amount of any such proceeds at this time.

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CERTAIN UNITED STATES FEDERAL INCOME TAX CONSEQUENCES

NW Holdings believes the following is an accurate summary of certain United States federal income tax consequences of participation in the Plan. This summary does not describe all of the material United States federal income tax considerations that may be relevant to participants in light of their particular circumstances or to participants that are subject to special rules, such as certain financial institutions, banks, insurance companies, tax-exempt entities, certain former citizens or residents of the United States, dealers in securities, traders in securities that elect to use a mark-to market method of accounting for federal income tax purposes, partnerships and other pass through entities and persons that would hold common stock as part of a hedge, straddle, constructive sale, conversion transaction or other integrated transaction and participants whose functional currency is not the U.S. dollar. This summary applies to U.S. taxpayers only, except where otherwise stated. In addition, this summary does not address the effect of any state, local or other tax laws, including non-U.S. tax laws, or any U.S. federal estate, gift or alternative minimum tax considerations. This summary is based upon the Internal Revenue Code of 1986, as amended (the Code), administrative pronouncements, judicial decisions and final, temporary and proposed regulations, all as in effect on the date hereof, and all of which are subject to change, possibly with retroactive effect. You are urged to consult your tax or financial advisor with respect to federal, state, local, and other tax laws which apply to your specific situation.

Dividend Reinvestment

With respect to reinvested cash dividends used to purchase shares in the open market, a participant will be treated for federal income tax purposes as having received on the dividend payment date a distribution in an amount equal to the cash reinvested, plus any brokerage fees paid by the Purchasing Agent to obtain the shares. That amount will be treated as dividend income to the participant to the extent of NW Holdings’ current or accumulated earnings and profits, as determined for federal income tax purposes. To the extent that such distribution exceeds NW Holdings’ current or accumulated earnings and profits, the excess will constitute a return of capital that will reduce your basis in NW Holdings common stock, but not below zero, and will then be treated as capital gain. The initial tax basis of the shares so purchased will be equal to the amount of the cash reinvested, plus any brokerage fees paid by the Purchasing Agent.

With respect to reinvested cash dividends that are used to acquire shares of common stock directly from NW Holdings, a participant will be treated for federal income tax purposes as having received on the dividend payment date a distribution in an amount equal to the fair market value on that date of the full number of shares and any fractional shares purchased with the reinvested dividends. The fair market value of those shares on the dividend payment date will be treated as dividend income to the participant to the extent of the current and accumulated earnings and profits of NW Holdings, as determined for federal income tax purposes. To the extent that such distribution exceeds NW Holdings’ current or accumulated earnings and profits, the excess will constitute a return of capital that will reduce your basis in NW Holdings common stock, but not below zero, and will then be treated as capital gain. The initial tax basis of the shares so purchased will be equal to the fair market value of those shares on the dividend payment date.

Certain dividends, as qualified dividend income to you, are currently eligible for the reduced maximum tax rate to individuals of 20% (lower rates apply to individuals in lower tax brackets). A dividend will not be treated as qualified dividend income to the extent that: (i) the shareholder has not held the shares on which the dividend was paid for more than 60 days during the 121-day period that begins on the date that is 60 days before the ex-dividend date; (ii) the shareholder is under an obligation (whether pursuant to a short sale or otherwise)to make related payments with respect to substantially similar or related property; or (iii) the shareholder elects to treat such dividend as investment income under section 163(d)(4)(B) of the Code. If such dividends do not qualify for the reduced rates, they will be taxable at regular ordinary income tax rates (at a maximum rate of 37%).

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In the case of corporate shareholders, dividends received under the Plan as described above will generally, and subject to certain limitations (including certain holding period limitations), be treated as a qualifying dividend. Corporate shareholders are generally entitled to a dividends-received deduction if certain conditions are satisfied.

In addition, investment earnings, such as dividends and gains from the sale or exchange of our common stock, will be subject to a 3.8% Medicare tax in the hands of individuals having adjusted gross income in excess of $200,000 ($250,000 if married and filing jointly) (Medicare Tax). The same tax will apply in the case of certain trusts and estates.

Other Purchases

Participants who purchase common stock through voluntary payments to the Plan are not treated for federal income tax purposes as recognizing income by virtue of the voluntary payment. A participant’s share of any brokerage commissions paid by the Purchasing Agent in respect of such purchases will constitute taxable income to such participant. The tax basis of shares of common stock purchased with optional cash payments will equal the amount invested, plus the amount included in income as a result of brokerage commissions paid by the Purchasing Agent in respect of such purchases.

Sales

Gain or loss will be recognized by a participant when whole and fractional shares are sold pursuant to the participant’s request to sell shares held in the Plan and when whole shares are sold by the participant. A participant who receives on termination of participation or termination of the Plan a cash adjustment for a fractional share interest will recognize gain or loss with respect to such fraction. Such gain or loss will be measured by the difference between the amount the participant receives and his or her tax basis for the shares, or fraction of a share, sold. Any gain or loss so recognized by a shareholder who is not a dealer in securities will generally, for individual shareholders, be treated as a long-term capital gain or loss if the shares have been held for more than twelve months and otherwise will be treated as a short-term capital gain or loss. Note that the Medicare Tax will apply to gains from the sale of our common stock.

Cost Basis

The statements you receive from the Agent are your continuing record of the cost of your purchases and should be retained for tax purposes.

Treasury Regulations require dividend reinvestment plan participants to reinvest at least 10% of all dividends (if any) paid on each share they hold in the Plan in order for the participants to use the “average basis method” when determining the tax basis of any shares sold. NW Holdings’ Plan has not adopted this requirement because it would force participants to reinvest dividends. Consequently, participants will not be able to use the “average basis method” in determining the tax basis of any shares they sell under the Plan. The Plan has adopted the first-in, first-out “FIFO” method as its default method when determining the tax basis of any shares sold. Participants may designate their preference for “specific identification” cost basis at the time of the request for the sale by identifying this preference in writing to the Agent.

Tax Reporting

The Internal Revenue Service (IRS) Form 1099-DIV mailed to each participant with respect to each year will report the dividend income realized by the participant during the year, including such participant’s share of brokerage fees paid by NW Holdings in respect of reinvested dividends or optional cash investments. That income may differ from the total of the reinvested dividends. An IRS Form 1099-B will be furnished to the participant in respect of any sales of shares through the Plan.

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Withholding

NW Holdings will be required in certain cases to withhold in the form of backup withholding at a 24% withholding rate and remit to the U.S. Treasury the amount withheld on amounts payable to any shareholder who: (i) has provided either an incorrect tax identification number or no number at all; (ii) is subject to backup withholding by the IRS for failure to properly report payments of interest or dividends; (iii) has failed to certify to NW Holdings that such shareholder is not subject to backup withholding; or (iv) has failed to certify to NW Holdings that the shareholder is a U.S. person (including a resident alien). Participants who are not U.S. persons (i.e., nonresident alien individuals and foreign corporations, partnerships, trusts and estates) are generally subject to U.S. withholding tax with respect to dividends on shares held in their accounts. The amount of withholding is determined in accordance with U.S. Treasury Regulations (which may, among other things, permit withholding from the gross amount of a dividend, without regard to earnings and profits) and is imposed at a 30% rate, unless a lower rate is provided for in an applicable income tax treaty. Other participants may be subject to U.S. backup withholding.

For participants who are subject to U.S. withholding tax or backup withholding, NW Holdings or the applicable withholding agent will withhold the required taxes from the gross dividends or proceeds from the sale of the shares. The dividends or proceeds of a sale received by the participant, or dividends reinvested on behalf of the participant, will be net of the withheld amounts. Additionally, dividends received by shareholders who own their shares through foreign accounts or foreign intermediaries will be subject to withholding tax at a 30% rate if certain disclosure requirements related to U.S. accounts or ownership are not satisfied (FATCA Rules). Beginning after December 31, 2018, the FATCA Rules will also apply to proceeds of sales in respect of NW Holdings shares.

The information explained above is only a summary and does not purport to be a complete description of all tax consequences of participation in the Plan. The description may be affected by future legislation, IRS rulings and regulations, or court decisions. In addition, the taxation of foreign shareholders, except as noted, is not discussed in this prospectus. Accordingly, you are urged to consult your own tax advisors with respect to the federal, state, local, foreign, and non-income tax consequences of your participation in the Plan.

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DESCRIPTION OF COMMON STOCK

General

The following is a summary of certain rights and privileges of NW Holdings’ common stock. This summary description does not purport to be complete. Reference is made to the laws of the State of Oregon, NW Holdings’ Amended and Restated Articles of Incorporation and Amended and Restated Bylaws, which are incorporated herein by reference. The following statements are qualified in their entirety by such references.

Under NW Holdings’ Amended and Restated Articles of Incorporation, NW Holdings is authorized to issue 100,000,000 shares of common stock and 3,500,000 shares of preferred stock. At October 1, 2018, 28,844,190 shares of common stock were outstanding and no shares of preferred stock were outstanding.

The Board of Directors is authorized under NW Holding’s Amended and Restated Articles of Incorporation to provide for the issuance from time to time of preferred stock in one or more series, and as to each series to fix and determine the relative rights and preferences, serial designation, dividend rate, redemption prices, voluntary and involuntary liquidation prices, sinking fund provisions for the redemption or purchase of shares, if any, and conversion provisions, if any, applicable to shares of such series.

Dividends and Liquidation Rights

Except as hereinafter stated, the common stock is entitled to receive such dividends as are declared by the Board of Directors and to receive ratably on liquidation any assets which remain after payment of liabilities. NW Holdings has an authorized class of senior capital stock, referred to as preferred stock, none of which is currently outstanding. NW Holdings’ preferred stock is entitled, in preference to the common stock, (1) to cumulative dividends at the annual rate fixed for each series by the Board of Directors, and (2) in voluntary and involuntary liquidation, to the amounts fixed for each series by the Board of Directors, plus in each case, unpaid accumulated dividends.

Dividend Limitations

Should dividends on the preferred stock be in arrears, no dividends on the common stock may be paid or declared. Future series of the preferred stock could contain sinking fund, purchase or redemption obligations under which no dividends on the common stock may be paid or declared while such obligations are in default. Common stock dividends also may be restricted by the provisions of future instruments pursuant to which NW Holdings may issue long-term debt.

Voting Rights

Except as provided by law or by resolutions establishing any series of preferred stock, only the common stock has voting rights. Cumulative voting is permitted by the Amended and Restated Articles of Incorporation to holders of common stock at elections of directors.

Classification of the Board of Directors

The Board of Directors of NW Holdings may consist of not less than nine nor more than thirteen persons, as determined by the Board, divided into three classes as nearly equal in number as possible. The number of directors as of the date of this prospectus is eleven. One class is elected for a three-year term at each annual meeting of shareholders. Vacancies, including those resulting from an increase in the size of the Board, may be filled by a majority vote of the directors then in office, to serve until the next annual meeting of shareholders. One or more of the directors may be removed, with or without cause, by the affirmative vote of the holders of not less than two-thirds of the shares entitled to vote thereon; provided, however, that if fewer than all of the

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directors should be candidates for removal, no one of them shall be removed if the votes cast against such director’s removal would be sufficient to elect such director if then cumulatively voted at an election of the class of directors of which such director shall be a part. Except for those persons nominated by the Board, no person shall be eligible for election as a director unless a request from a shareholder entitled to vote in the election of directors that such person be nominated and such person’s consent thereto shall be delivered to the Secretary of NW Holdings within the time period specified in advance of the meeting at which such election shall be held. The foregoing provisions may not be amended or repealed except by the affirmative vote of the holders of not less than two-thirds of the shares entitled to vote at an election of directors.

Business Transactions with Related Persons

NW Holdings shall not enter into any business transaction with a related person or in which a related person shall have an interest (except proportionately as a shareholder of NW Holdings) without first obtaining both (1) the affirmative vote of the holders of not less than two-thirds of the outstanding shares of the capital stock of NW Holdings not held by such related person, and (2) the determination of a majority of the continuing directors that the cash or fair market value of the property, securities or other consideration to be received per share by the holders, other than such related person, of the shares of each class or series of the capital stock of NW Holdings in such business transaction shall not be less than the highest purchase price paid by such related person in acquiring any of its holdings of shares of the same class or series, unless the continuing directors by a majority vote shall either (a) have expressly approved the acquisition of the shares of the capital stock of NW Holdings that caused such related person to become a related person, or (b) have expressly approved such business transaction. As used in this paragraph: a “business transaction” includes a merger, consolidation, plan of exchange or recapitalization, a purchase, sale, lease, exchange, transfer, mortgage or other disposition of all or a substantial part (10% or more of the fair market value of the assets) of the property and assets of NW Holdings or a related person, an issuance, sale, exchange or other disposition of securities of NW Holdings and a liquidation, spin-off or dissolution; a “related person” includes a person, organization or group thereof owning 10% or more of the capital stock of NW Holdings; “continuing directors” are those directors who were directors of NW Holdings on the date the Amended and Restated Articles of Incorporation first became effective or whose nominations have been approved by a majority of the then continuing directors. The foregoing provisions may not be amended or repealed except by the affirmative vote of the holders of not less than two-thirds of the shares of the capital stock of NW Holdings (other than shares held by related persons).

Preemptive Rights

The holders of the common stock have no preemptive rights.

Certain Anti-Takeover Matters

NW Holdings’ Amended and Restated Articles of Incorporation and Amended and Restated Bylaws include a number of provisions that may have the effect of discouraging persons from acquiring large blocks of its stock or delaying or preventing a change in its control. The material provisions that may have such an effect include:

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NW Holdings is subject to the provisions of sections 60.825 to 60.845 of the Oregon Business Corporation Act (Oregon Business Combinations Act) which generally provide that in the event a person or entity acquires 15% or more of NW Holdings’ voting stock (Interested Shareholder), NW Holdings and such Interested Shareholder and any affiliate may not engage in the following business combinations for a period of three years following the date that person became an Interested Shareholder:

These restrictions do not apply if:

NW Holdings is also subject to the provisions of Sections 60.801 to 60.816 of the Oregon Business Corporation Act (Oregon Control Share Act), which generally provide that a person who acquires voting stock in a transaction which results in such person holding more than 20%, 33-1/3% or 50% of the total voting power cannot vote the shares it acquires in the acquisition unless voting rights are accorded to such control shares by the holders of a majority of the outstanding voting shares, excluding the control shares held by such person and shares held by officers and inside directors, and by the holders of a majority of the outstanding voting shares, including the control shares held by such person and shares held by officers and inside directors. This vote would be required at the time an acquiring person’s holdings exceed 20% of the total voting power, and again at the time the acquiring person’s holdings exceed 33-1/3% and 50%, respectively. The acquiring person may, but is not required to, submit to NW Holdings an “acquiring person statement” setting forth certain information about the acquiring person and its plans with respect to NW Holdings. The acquiring person statement may also request that NW Holdings call a special meeting of shareholders to determine whether the control shares will be allowed to retain voting rights. If the acquiring person does not request a special meeting of shareholders, the issue of voting rights of control shares will be considered at the next annual meeting or special meeting of shareholders that is held more than 60 days after the date of the acquisition of control shares. Shares are not deemed to be acquired in a control share acquisition if, among other things, they are acquired from the issuing corporation, or are issued pursuant to a plan of merger or exchange effected in compliance with the Oregon Business Corporation Act and the issuing corporation is a party to the merger or exchange agreement.

The Oregon Control Share Act and the Oregon Business Combinations Act have anti-takeover effects because they will encourage any potential acquirer to negotiate with NW Holdings’ Board of Directors and will also discourage potential acquirers unwilling to comply with the provisions of these laws. An Oregon corporation

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may provide in its articles of incorporation or bylaws that the laws described above do not apply to its shares. NW Holdings has not adopted such a provision.

NW Holdings is also subject to Oregon Revised Statutes Chapter 757.511 which generally provides that no person, directly or indirectly, shall acquire the power to exercise any substantial influence over the policies and actions of a public utility without first securing from the Oregon Public Utility Commission (OPUC) an order authorizing such acquisition if such person is, or by such acquisition would become, an “affiliated interest” with such public utility as defined by Oregon law. Any applicant requesting such an order bears the burden of showing that granting the application is in the public interest. This provision of Oregon law may have anti-takeover effects by subjecting potential acquisitions to OPUC review and approval.

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EXPERTS

The financial statements and management’s assessment of the effectiveness of internal control over financial reporting (which is included in Management’s Report on Internal Control over Financial Reporting) incorporated in this Prospectus by reference to NW Natural’s Current Report on Form 8-K dated September 24, 2018 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

LEGALITY

The legality of the common stock will be passed upon for NW Holdings by MardiLyn Saathoff, Esquire, Senior Vice President and General Counsel of NW Holdings, and by Morgan, Lewis & Bockius LLP, New York, New York. Ms. Saathoff may rely upon the opinion of Morgan, Lewis & Bockius LLP as to certain legal matters arising under New York law. Morgan, Lewis & Bockius LLP may rely upon the opinion of Ms. Saathoff as to certain legal matters arising under Oregon law. Ms. Saathoff is regularly employed by NW Holdings, participates in various NW Holdings employee benefit plans under which she may receive shares of common stock and currently beneficially owns less than one percent of the outstanding shares of common stock of NW Holdings.

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PROSPECTUS

NORTHWEST NATURAL GAS COMPANY

DEBT SECURITIES

PREFERRED STOCK

Northwest Natural Gas Company (NW Natural) may offer any combination of the securities described in this prospectus in one or more offerings from time to time and in amounts authorized from time to time. NW Natural will provide specific terms of its securities, including their offering prices, in supplements to this prospectus. The supplements may also add, update or change information contained in this prospectus. You should read this prospectus and any supplements carefully before you invest.

NW Natural may offer these securities directly or through underwriters, agents or dealers. The supplements to this prospectus will describe the terms of any particular plan of distribution, including any underwriting arrangements. The “Plan of Distribution” section on page 20 of this prospectus also provides more information on this topic.

See the discussion of risk factors on page 3 of this prospectus and as contained in NW Natural’s annual, quarterly and current reports filed with the Securities and Exchange Commission (SEC) under the Securities Exchange Act of 1934, as amended (Exchange Act), which are incorporated by reference into this prospectus, to read about certain factors you should consider before purchasing any of the securities being offered.

NW Natural’s principal executive offices are located at One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209, and its telephone number is (503) 226-4211.

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

The date of this prospectus is October 2, 2018.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that NW Natural filed with the SEC utilizing a “shelf” registration, or continuous offering, process. Under this shelf registration or continuous offering process, NW Natural, from time to time, may sell any combination of the securities described in this prospectus in one or more offerings. NW Natural may offer Debt Securities or Preferred Stock.

This prospectus provides you with a general description of the securities that NW Natural may offer. Each time NW Natural sells securities, it will provide a prospectus supplement that will contain specific information about the terms of that offering. Material United States federal income tax considerations applicable to the offered securities will be discussed in the applicable prospectus supplement, if necessary. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described under the heading “Where You Can Find More Information.”

For more detailed information about the securities, you can read the exhibits to the registration statement. Those exhibits have been either filed with the registration statement or incorporated by reference to earlier SEC filings listed in the registration statement.

WHERE YOU CAN FIND MORE INFORMATION

NW Natural files annual, quarterly and other reports and other information with the SEC. Reports, proxy statements and other information filed by NW Natural can be read and copied at the public reference room of the SEC, 100 F Street, N.E., Washington, D.C. 20549. You can obtain additional information about the Public Reference Room by calling the SEC at 1-800-SEC-0330.

In addition, the SEC maintains a Web site (http://www.sec.gov) that contains reports, proxy statements and other information filed electronically by NW Natural. NW Natural’s parent, Northwest Natural Holding Company (NW Holdings), also maintains a Web site (http://www.nwnatural.com). Information contained on NW Holdings’ Web site does not constitute part of this prospectus and is not incorporated by reference into this prospectus. The reference to NW Holdings’ Web site is intended to be an inactive textual reference only.

The SEC allows NW Natural to “incorporate by reference” the information that NW Natural files with the SEC, which means that NW Natural may, in this prospectus, disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus. NW Natural is incorporating by reference the documents listed below (other than any portions of such documents that are deemed to be furnished and not filed) and any future filings NW Natural makes with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, until NW Natural sells all of the securities described in this prospectus or the offering that this prospectus relates to is terminated. Information that NW Natural files in the future with the SEC will automatically update and supersede this information.

We hereby incorporate by reference into this prospectus the following documents that we have filed with the SEC:

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You may request a copy of these documents, at no cost to you, by writing or calling Shareholder Services, Northwest Natural Gas Company, One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209, telephone 503-226-4211, extension 2402.

You should rely only on the information contained, or incorporated by reference, in this prospectus and any prospectus supplement. NW Natural has not, and any underwriters, agents or dealers have not, authorized anyone else to provide you with different information. NW Natural is not, and any underwriters, agents or dealers are not, making an offer of these securities or soliciting offers to buy these securities in any jurisdiction where the offer or solicitation is not permitted. You should not assume that the information contained in this prospectus and any prospectus supplement is accurate as of any date other than the date on the front of such document or that the information incorporated by reference in this prospectus or any prospectus supplement is accurate as of any date other than the date of the document incorporated by reference.

FORWARD-LOOKING STATEMENTS

This prospectus does, and the documents incorporated herein by reference may, contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (Securities Act), and Section 21E of the Exchange Act. Although NW Natural believes these statements are based on reasonable assumptions, no assurance can be given that actual results will not differ from those in the forward-looking statements contained herein and in the incorporated documents. The forward-looking statements contained herein and in the incorporated documents may be affected by various uncertainties. For a further discussion of forward-looking statements and of factors which may affect forward-looking statements contained herein and in the incorporated documents, see NW Natural’s most recent Annual Report on Form 10-K, any of its Quarterly Reports on Form 10-Q and any of its Current Reports on Form 8-K filed after that Annual Report on Form 10-K, as well as other filings made with the SEC that are incorporated by reference into this prospectus.

NW NATURAL

NW Natural is principally engaged in the distribution of natural gas in Oregon and southwest Washington. NW Natural and its predecessors have supplied gas service to the public since 1859. NW Natural is a wholly-owned subsidiary of NW Holdings, which is a utility holding company primarily engaged, through NW Natural, in the distribution of natural gas. NW Natural’s executive offices are located at One Pacific Square, 220 N.W. Second Avenue, Portland, Oregon 97209. Its telephone number is 503-226-4211.

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RISK FACTORS

Investing in the securities involves certain risks. You are urged to read and consider the risk factors described in NW Natural’s annual, quarterly and current reports filed with the SEC under the Exchange Act, which are incorporated by reference into this prospectus. Before making an investment decision, you should carefully consider these risks as well as other information NW Natural includes or incorporates by reference into this prospectus. You should also be aware that new risks may emerge in the future at any time, and NW Natural cannot predict such risks or estimate the extent to which they may affect NW Natural’s financial condition or performance. The prospectus supplement applicable to each type or series of securities NW Natural offers may contain a discussion of additional risks applicable to an investment in NW Natural and the particular type of securities NW Natural is offering under that prospectus supplement.

USE OF PROCEEDS

Unless otherwise stated in a prospectus supplement, the net proceeds to be received by NW Natural from the sale of these securities will be added to the general funds of NW Natural and used for corporate purposes, primarily to fund, in part, NW Natural’s ongoing utility construction program and for general corporate purposes.

The prospectus supplement relating to a particular offering of securities will identify the use of proceeds for that offering.

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RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO

COMBINED FIXED CHARGES AND PREFERENCE DIVIDENDS

The ratios of earnings to fixed charges and the ratios of earnings to combined fixed charges and preference dividends, calculated according to the rules set forth under the Securities Act, for the following periods were:

Earnings consist of net income from continuing operations to which has been added taxes on income from continuing operations and fixed charges. Fixed charges consist of interest on all indebtedness, amortization of debt expense and discount or premium, and the estimated interest portion of rentals charged to income. Preference dividends are the amounts of pre-tax earnings from continuing operations that would be required to pay dividends on any outstanding preference equity securities (which could include any NW Natural preferred stock outstanding for the period).

DESCRIPTION OF DEBT SECURITIES

General

The following sections set forth certain general terms and provisions of NW Natural’s secured, unsecured and junior subordinated debt securities, consisting of first mortgage bonds and debentures, notes or other debt, that NW Natural may offer by this prospectus. NW Natural will describe the particular terms of the debt securities, and provisions that vary from those described below, in one or more prospectus supplements.

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DESCRIPTION OF THE BONDS

General

NW Natural will issue its first mortgage bonds, in one or more series, under the Mortgage and Deed of Trust, dated as of July 1, 1946, to Deutsche Bank Trust Company Americas (formerly known as Bankers Trust Company) (the Corporate Trustee), as trustee (the Mortgage Trustee), which has been amended and supplemented in the past and which may be supplemented again by one or more supplemental indentures relating to these securities. This Mortgage and Deed of Trust, as amended and supplemented, is referred to in this prospectus as the “Mortgage.” All first mortgage bonds issued or to be issued under the Mortgage, including the first mortgage bonds offered by this prospectus, are referred to herein as “First Mortgage Bonds.”

This section briefly summarizes some of the provisions of the First Mortgage Bonds and some of the provisions of the Mortgage and uses some terms that are not defined in this prospectus but that are defined in the Mortgage. This summary is not complete and is qualified in its entirety by reference to the Mortgage which has been filed with the SEC and is an exhibit to the registration statement filed with the SEC of which this prospectus is a part. You should read the Mortgage for a complete understanding of the provisions that may be important to you and for the definitions of some terms used in this summary.

Each series of First Mortgage Bonds may have different terms. NW Natural will include some or all of the following information about a specific series of First Mortgage Bonds in the prospectus supplement relating to those First Mortgage Bonds:

Except as may otherwise be described in a prospectus supplement, the covenants contained in the Mortgage will not afford holders of the First Mortgage Bonds protection in the event of a highly-leveraged or similar transaction involving NW Natural or in the event of a change in control.

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Reserved Amendment Rights

NW Natural has reserved the right to amend the Mortgage, without the consent or other action of the holders of any series of First Mortgage Bonds created after November 1, 2016 or Secured Medium-Term Notes, Series B with an issue date after November 1, 2016, to make the changes described below in this “Description of First Mortgage Bonds.” Holders of any series of First Mortgage Bonds created after November 1, 2016 and Secured Medium-Term Notes, Series B with an issue date after November 1, 2016, including First Mortgage Bonds that NW Natural may offer by this prospectus, are deemed to have consented to these amendments. This section briefly summarizes the reserved amendment rights. This summary is not complete. You should read this summary together with the twenty-second supplemental indenture, dated as of November 1, 2016, which has been filed with the SEC and is an exhibit to the registration statement filed with the SEC of which this prospectus is a part, together with the Mortgage for a complete understanding of the reserved amendment rights.

Form, Exchange and Payment

Unless otherwise specified in the prospectus supplement relating to First Mortgage Bonds, First Mortgage Bonds will be (1) issued in fully registered form in denominations of $1,000 or any amount in excess thereof that is an integral multiple of $1,000 and (2) exchangeable at the office of Deutsche Bank Trust Company Americas in New York City, without charge other than taxes or other governmental charges incident thereto, and principal, premium, if any, and interest will be payable at such office.

Security

First Mortgage Bonds issued or to be issued under the Mortgage are or will be secured by the Mortgage, which constitutes a first mortgage lien on certain gas utility properties owned from time to time by NW Natural (except as stated below).

The lien of the Mortgage is or may be subject to the following Excepted Encumbrances:

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In addition, the lien of the Mortgage is or may be subject to the following:

NW Natural has reserved the right to amend the Mortgage to restate the definition of Excepted Encumbrances to mean substantially the following:

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The following are excepted from the lien of the Mortgage:

No stock, properties or other assets of NW Natural subsidiaries are subject to the Mortgage.

The Mortgage contains provisions that impose the lien of the Mortgage on property acquired by NW Natural after the date of the Mortgage, other than the excepted property described above and subject to pre-existing liens. However, if NW Natural consolidates, merges or sells substantially all of its assets to another entity, the lien created by the Mortgage will generally not cover the property of the successor, other than the mortgaged property it acquires from NW Natural and improvements, extensions, additions, renewals and replacements of that property. (See Mortgage, Article XVI.)

The Mortgage provides that the Mortgage Trustee shall have a lien upon the mortgaged property, prior to that of the First Mortgage Bonds, for the payment of its reasonable compensation and expenses and for indemnity against certain liabilities. This lien takes priority over the lien securing the First Mortgage Bonds. (See Mortgage, Section 96.)

NW Natural has reserved the right to amend the Mortgage to add any one or more of following types of property to the list of excepted property described above:

NW Natural has also reserved the right to amend the Mortgage to subject any excepted property to the lien of the Mortgage and to define the term “mineral rights” for purposes of the Mortgage to exclude any rights or other property constructed, acquired or held primarily for the purpose of storing and withdrawing gas that has been injected into, or may from time to time may be injected into, storage reservoirs or other facilities located on or under real property, whether or not such rights or other property constitute “mineral rights” under applicable law. (See Twenty-second Supplemental Indenture, Sections 2.05, 2.08 and 2.23.)

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Issuance of Additional First Mortgage Bonds

First Mortgage Bonds may be issued from time to time on the basis of:

With certain exceptions in the case of (2) above, the issuance of First Mortgage Bonds must meet an earnings test. The adjusted net earnings before income taxes for 12 consecutive months out of the preceding 15 months must be at least twice the annual interest requirements on all First Mortgage Bonds at the time outstanding, including the First Mortgage Bonds being issued, and all indebtedness of prior rank.

For purposes of determining annual interest requirements, interest on First Mortgage Bonds or other indebtedness bearing interest at a variable interest rate shall be computed at the average of the interest rates borne by such First Mortgage Bonds or other indebtedness during the period of calculation or, if such First Mortgage Bonds or other indebtedness shall have been issued after such period or shall be the subject of pending applications, interest shall be computed at the initial rate borne upon issuance.

Property additions generally include gas, electric, steam or hot water property or gas by-product property acquired after March 31, 1946, but will not include certain assets, including securities, airplanes, automobiles or other vehicles, or natural gas transmission lines or Natural Gas and Oil Production Property. As of June 30, 2018, approximately $335.1 million of property additions were available for use as the basis for the issuance of First Mortgage Bonds. As of June 30, 2018, approximately $460.3 million of retired First Mortgage Bonds were available for use as the basis for the issuance of First Mortgage Bonds.

The Mortgage contains certain restrictions upon the issuance of First Mortgage Bonds against property subject to liens.

(See Mortgage, Sections 4-7, 20-30 and 46, Third Supplemental Indenture, Sections 3 and 4, Eighteenth Supplemental Indenture, Section 2.01, and Twenty-second Supplemental Indenture, Sections 1.03 and 1.04.)

NW Natural has reserved the right to amend the Mortgage (1) to delete the earnings test and (2) to modify the definition of property additions to mean all mortgaged property acquired or constructed by NW Natural after March 31, 1946. (See Twenty-second Supplemental Indenture, Sections 2.01 and 2.05.)

NW Natural has also reserved the right to amend the Mortgage to change the definition of funded property from time to time. To change the definition of funded property, NW Natural must deliver to the Corporate Trustee an independent engineer’s certificate referred to as a “funded property certificate.” This funded property certificate will describe all or a portion of mortgaged property which has a fair value not less than the sum of the principal amount of the First Mortgage Bonds outstanding and the principal amount of the First Mortgage Bonds that NW Natural is entitled to have authenticated on the basis of retired First Mortgage Bonds divided by 70%. Once this funded property certificate is delivered to the Corporate Trustee, the definition of “funded property” will mean any mortgaged property described in the funded property certificate. Property additions will become funded property when used under the Mortgage for the issuance of bonds, the release or retirement of funded property, or the withdrawal of cash deposited with the Corporate Trustee for the issuance of bonds or the release of Funded property. (See Twenty-second Supplemental Indenture, Section 2.03.)

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Release and Substitution of Property

Property may be released from the lien of the Mortgage, at the lesser of its cost or its fair value at the time that such property became funded property, on the basis of:

Cash so deposited as the basis for a release and cash deposited as the basis for the issuance of additional First Mortgage Bonds may be withdrawn upon the bases stated in (2) and (3) above without applying an earnings test. When property released is not funded property, property additions used to effect the release may again, in certain cases, become available as credits under the Mortgage, and the waiver of the right to issue First Mortgage Bonds to effect the release may, in certain cases, cease to be effective as such a waiver. Similar provisions are in effect as to cash proceeds of such property. The Mortgage contains special provisions with respect to qualified lien bonds pledged and the disposition of moneys received on pledged prior lien bonds. In addition, NW Natural may release unfunded mortgaged property if after such release at least one dollar of unfunded mortgaged property remains subject to the lien of the Mortgage. (See Mortgage, Sections 5, 31, 32, 37, 46 to 50, 59 to 61, 100 and 118, Eighteenth Supplemental Indenture, Section 2.03, and Twenty-second Supplemental Indenture, Sections 1.02 and 1.06.)

NW Natural has reserved the right to amend the Mortgage as follows:

Satisfaction and Discharge of Mortgage

The lien of the Mortgage may be canceled and discharged whenever all indebtedness secured by the Mortgage has been paid. First Mortgage Bonds, or any portion of the principal amount thereof, will, prior to the maturity thereof, be deemed to have been paid for purposes of satisfying the lien of the Mortgage and shall not be deemed to be outstanding for any other purpose of the Mortgage if there shall have been deposited with the Corporate Trustee either:

which in any case are not subject to redemption prior to maturity by anyone other than the holders, and the principal of and the interest on which when due, and without any regard to reinvestment thereof, shall be sufficient to pay when due the principal of, premium, if any, and interest due and to become due on said First Mortgage Bonds or portions thereof on the redemption date or maturity date thereof, as the case may be. (See Mortgage, Section 106 and Thirteenth Supplemental Indenture, Section 3.02.)

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Defaults and Notice Thereof

Defaults are:

The Mortgage Trustee may withhold notice of default (except in payment of principal, interest or any fund for the retirement of First Mortgage Bonds) if it thinks it is in the interest of the bondholders. (See Mortgage, Sections 65 and 66.)

Holders of 25% of the First Mortgage Bonds may declare the principal and the interest due on default, but a majority may annul such declaration if such default has been cured. There is no automatic acceleration even in the event of NW Natural’s bankruptcy, insolvency or reorganization. No holder of First Mortgage Bonds may enforce the lien of the Mortgage without giving the Mortgage Trustee written notice of a default and unless holders of 25% of the First Mortgage Bonds have requested the Mortgage Trustee to act and offered it reasonable opportunity to act and the Mortgage Trustee has failed to act. The Mortgage Trustee is not required to risk its funds or incur personal liability if there is reasonable ground for believing that the repayment is not reasonably assured. Holders of a majority of the First Mortgage Bonds may direct the time, method and place of conducting any proceedings for any remedy available to the Mortgage Trustee, or exercising any trust or power conferred upon the Mortgage Trustee, but the Mortgage Trustee is not required to follow such direction if not sufficiently indemnified for expenditures. (See Mortgage, Sections 67, 71, 80 and 94.)

Evidence to be Furnished to the Mortgage Trustee

Compliance with the Mortgage provisions is evidenced by written statements of NW Natural’s officers or persons selected by NW Natural. In certain major matters the accountant, engineer, appraiser or other expert must be independent. Various certificates and other papers, including an annual certificate with reference to compliance with the terms of the Mortgage and absence of defaults, are required to be filed annually and upon the occurrence of certain events. (See Mortgage, Sections 38, 41-46 and 121.)

Modification of the Mortgage

The rights of the bondholders may be modified with the consent of holders of 66 2/3% of the First Mortgage Bonds and, if less than all series of First Mortgage Bonds are affected, the consent also of holders of 66 2/3% of First Mortgage Bonds of each series affected. In general, no modification of the terms of payment of principal and interest, permitting liens prior or equal to the lien of the Mortgage, depriving a non-assenting bondholder of the benefit of a lien on the mortgaged property or reducing the percentage required for modification (except as provided above) will be effective against any bondholder without his or her consent. (See Ninth Supplemental Indenture, Section 6, and Twenty-second Supplemental Indenture, Section 1.01.)

NW Natural has reserved the right to amend the Mortgage to provide that the rights of the bondholders (other than those described above that require the consent of each affected bondholder) may be modified with the consent of the holders of a majority in aggregate principal amount of then outstanding First Mortgage Bonds, considered as one class, or if less than all of the series of First Mortgage Bonds outstanding are directly affected by a proposed amendment or modification, then the consent of the holders of only a majority in aggregate principal amount of the outstanding First Mortgage Bonds of all series that are directly affected, considered as one class. (See Twenty-second Supplemental Indenture, Section 2.15.)

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NW Natural has reserved the right to amend the Mortgage to permit NW Natural and the Corporate Trustee, without the consent of any holder of First Mortgage Bonds, to enter into one or more supplemental indentures for any of the following purposes:

Consolidation, Merger and Conveyance of Assets

The Mortgage provides that NW Natural may consolidate with or merge into any other entity or convey, transfer or lease as, or substantially as, an entirety to any entity the mortgaged property, if:

In the case of the conveyance or other transfer of the mortgaged property as, or substantially as, an entirety to another corporation, upon the satisfaction of all the conditions described above, such corporation would succeed and be substituted for NW Natural under the Mortgage.

The Mortgage does not prevent or restrict any conveyance or other transfer, or lease, of any part of the mortgaged property that does not constitute the entirety, or substantially the entirety, of the mortgaged property.

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Although NW Natural’s successor may, in its sole discretion, subject to the lien of the Mortgage any property then owned or thereafter acquired by the successor, the lien of the Mortgage generally will not cover the property of the successor other than the mortgaged property it acquires from NW Natural and improvements, extensions and additions to such property and renewals, replacements and substitutions thereof, within the meaning of the Mortgage.

The terms of the Mortgage do not restrict mergers in which NW Natural is the surviving entity. (See Mortgage, Sections 85, 86 and 87.)

NW Natural has reserved the right to amend the Mortgage as follows:

The Corporate Trustee

Deutsche Bank Trust Company Americas also serves as the Indenture Trustee under the Indenture under which the Indenture Securities, as defined below, are issued.

NW Natural has reserved the right to amend the Mortgage without the consent or other action by the holders of First Mortgage Bonds to provide that, so long as no default has occurred and is continuing and except with respect to a Corporate Trustee appointed by act of the bondholders, if NW Natural has delivered to the Corporate Trustee a board resolution appointing a successor Corporate Trustee and the successor has accepted the appointment in accordance with the terms of the Mortgage, the Corporate Trustee will be deemed to have resigned and the successor will be deemed to have been appointed as Corporate Trustee in accordance with the Mortgage. (See Twenty-second Supplemental Indenture, Section 2.11.)

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DESCRIPTION OF THE UNSECURED DEBT SECURITIES

General

NW Natural will issue its unsecured debt securities, in one or more series, under an Indenture, dated as of June 1, 1991, between NW Natural and Deutsche Bank Trust Company Americas, as trustee (Indenture Trustee). This Indenture, as it may be amended and supplemented from time to time, is referred to in this prospectus as the “Indenture.” These unsecured debt securities offered by this prospectus are referred to in this prospectus as the “Unsecured Debt Securities.”

The Indenture provides for the issuance of debentures, notes or other debt by NW Natural in an unlimited amount from time to time. The Unsecured Debt Securities and all other debentures, notes or other debt of NW Natural issued or to be issued under the Indenture are collectively referred to in this prospectus as the “Indenture Securities.”

The Indenture does not limit the amount of debt, secured or unsecured, which may be issued by NW Natural.

Indenture Securities will rank equally with all other unsecured and unsubordinated indebtedness of NW Natural. Substantially all of the gas plants, distribution systems and certain other materially important physical properties of NW Natural are subject to the lien of the Mortgage securing the First Mortgage Bonds. (See “Description of the Bonds—Security” and “—Issuance of Additional First Mortgage Bonds”, above.)

This section briefly summarizes some of the provisions of the Unsecured Debt Securities and some of the provisions of the Indenture and uses some terms that are not defined in this prospectus but that are defined in the Indenture. This summary is not complete and is qualified in its entirety by the Indenture which is on file with the SEC. You should read the Indenture for a complete understanding of the provisions that may be important to you and for the definitions of some terms used in this summary.

Each series of Unsecured Debt Securities may have different terms. NW Natural will include some or all of the following information about a specific series of Unsecured Debt Securities in the prospectus supplement(s) relating to those Unsecured Debt Securities:

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Except as may otherwise be described in a prospectus supplement, the covenants contained in the Indenture will not afford holders of the Unsecured Debt Securities protection in the event of a highly-leveraged or similar transaction involving NW Natural or in the event of a change in control.

Form, Exchange and Payment

Unless otherwise specified in the prospectus supplement relating to the Unsecured Debt Securities, the Unsecured Debt Securities will be (1) issued in fully registered form in denominations of $1,000 or any amount in excess thereof that is an integral multiple of $1,000 and (2) exchangeable at the office of Deutsche Bank Trust Company Americas in New York City, without charge other than taxes or other governmental charges incident thereto, and principal, premium, if any, and interest will be payable at such office.

Defeasance

The principal amount of the Unsecured Debt Securities of any series issued under the Indenture will be deemed to have been paid for purposes of the Indenture and the entire indebtedness of NW Natural in respect thereof will be deemed to have been satisfied and discharged, if there shall have been irrevocably deposited with the Indenture Trustee, in trust:

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to pay when due the principal of and premium, if any, and interest, if any, due and to become due on the Unsecured Debt Securities of that series that are outstanding. For this purpose, Government Obligations include direct obligations of, or obligations unconditionally guaranteed by, the United States of America entitled to the benefit of the full faith and credit thereof and certificates, depositary receipts or other instruments which evidence a direct ownership interest in such obligations or in any specific interest or principal payments due in respect thereof. (See Indenture, Sections 101, 701.)

If NW Natural deposits any money and/or Government Obligations with respect to the Unsecured Debt Securities of any series, or any portion of the principal amount thereof, prior to the maturity or redemption of such Unsecured Debt Securities or such portion of the principal amount thereof, for the satisfaction or discharge of the indebtedness of NW Natural in respect to such Unsecured Debt Securities or such portion thereof as described in Section 701 of the Indenture, NW Natural shall deliver to the Indenture Trustee either:

In the event that NW Natural shall elect to deliver to the Indenture Trustee an instrument as described in clause (1) of the preceding paragraph in connection with any such deposit of money and/or Government Obligations with the Indenture Trustee, under current applicable United States federal income tax regulations, the holders of such Unsecured Debt Securities, or such portions thereof, will not recognize income, gain or loss for United States federal income tax purposes as a result of such satisfaction and discharge and will be subject to United States federal income tax on the same amounts, at the same times and in the same manner as if such deposit had not been effected. There can be no assurance that such United States federal income tax regulations will not change such that, as a result of such deposit and delivery by NW Natural of such instrument, holders of Unsecured Debt Securities may recognize income, gain or loss for United States federal income tax purposes and may not be subject to United States federal income tax on the same amounts, at the same times and in the same manner as if such deposit had not been made.

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Events of Default and Notice Thereof

Events of default are:

No event of default with respect to a series of Indenture Securities necessarily constitutes an event of default with respect to the Indenture Securities of any other series.

The Indenture Trustee may withhold notice of default (except in payment of principal, interest or any funds for the retirement of Indenture Securities) if it, in good faith, determines that withholding of such notice is in the interest of the holders of the Indenture Securities. (See Indenture, Sections 801 and 903.)

Either the Indenture Trustee or the holders of not less than 33% in principal amount (or such lesser amount as may be provided in the case of discount Indenture Securities) of the outstanding Indenture Securities of all defaulted series, considered as one class, may declare the principal and interest on such series due on default, but NW Natural may annul such default by effecting its cure and paying overdue interest and principal. There is no automatic acceleration even in the event of NW Natural’s bankruptcy, insolvency or reorganization. No holder of Indenture Securities may enforce the Indenture without having given the Indenture Trustee written notice of default, and unless the holders of a majority of the Indenture Securities of all defaulted series, considered as one class, shall have requested the Indenture Trustee to act and offered reasonable indemnity, and for 60 days the Indenture Trustee shall have failed to act. But, each holder has an absolute right to receive payment of principal and interest when due and to institute suit for the enforcement of such payment. The Indenture Trustee is not required to risk its funds or incur any financial liability if it has reasonable grounds to believe that repayment is not reasonably assured.

The holders of a majority of the Indenture Securities of all defaulted series, considered as one class, may direct the time, method and place of conducting any proceedings for any remedy available to the Indenture Trustee, or exercising any trust or power conferred on the Indenture Trustee, with respect to the Indenture Securities of such series, but the Indenture Trustee is not required to follow such direction if not sufficiently indemnified and the Indenture Trustee may take any other action it deems proper which is not inconsistent with such direction. (See Indenture, Sections 802, 807, 808, 812 and 902.)

Evidence to be Furnished to the Indenture Trustee

Compliance with the Indenture provisions will be evidenced by written statements of NW Natural’s officers. An annual certificate with reference to compliance with the covenants and conditions of the Indenture and the absence of defaults is required to be filed with the Indenture Trustee. (See Indenture, Section 1004.)

Modification of the Indenture

The rights of the holders of the Indenture Securities may be modified with the consent of the holders of a majority of the Indenture Securities of all series or Tranches, as defined below, affected, considered as one class. However, certain specified rights of the holders of Indenture Securities may be modified without the consent of the holders if such modification would not be deemed to adversely affect their interests in any material respect.

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In general, no modification of the terms of payment of principal and interest, no reduction of the percentage in principal amount of the Indenture Securities outstanding under such series required to consent to any supplemental indenture or waiver under the Indenture, no reduction of such percentage necessary for quorum and voting, and no modification of certain of the provisions in the Indenture relating to supplemental indentures, waivers of certain covenants and waivers of past defaults is effective against any holder of Indenture Securities without the consent of such holder. “Tranche” means a group of Indenture Securities which are of the same series and have identical terms except as to principal amount and/or date of issuance. (See Indenture, Article Twelve.)

The Indenture Trustee

Deutsche Bank Trust Company Americas also serves as the Corporate Trustee under the Mortgage under which the First Mortgage Bonds are issued.

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DESCRIPTION OF PREFERRED STOCK

General

The following is a summary of certain rights and privileges of NW Natural’s preferred stock. This summary description does not purport to be complete. Reference is made to the laws of the State of Oregon, NW Natural’s Amended and Restated Articles of Incorporation and Bylaws, and any articles of amendment to the Amended and Restated Articles of Incorporation establishing a particular series of preferred stock that are filed with the SEC and incorporated herein by reference. The following statements are qualified in their entirety by such references.

The Board of Directors is authorized under NW Natural’s Amended and Restated Articles of Incorporation to provide for the issuance from time to time of preferred stock in one or more series, and as to each series to fix and determine the relative rights and preferences, serial designation, dividend rate, redemption prices, voluntary and involuntary liquidation prices, sinking fund provisions for the redemption or purchase of shares, if any, and conversion provisions, if any, applicable to shares of such series. NW Natural will include some or all of this information about a specific series of preferred stock being offered under this prospectus in the prospectus supplement(s) relating to such series. As used herein, the term “preferred stock” includes all series.

Under NW Natural’s Amended and Restated Articles of Incorporation, NW Natural is authorized to issue 100,000,000 shares of common stock, 3,500,000 shares of preferred stock and one share of a separate class of junior preferred stock. The junior preferred stock is not entitled to receive or participate in any dividends and does not have any voting rights other than as required by law except that NW Natural may not commence a voluntary bankruptcy filing without the consent of the holder of the junior preferred stock. At October 1, 2018, no shares of preferred stock and one share of junior preferred stock were outstanding and all of NW Natural’s common stock was held by its parent, NW Holdings.

Dividends and Liquidation Rights

Each series of the preferred stock shall be entitled, in preference to the common stock, (1) to dividends cumulative from the date of issue, at the rate fixed by the Board of Directors, payable quarterly on February 15, May 15, August 15 and November 15 in each year or on such other date or dates as the Board of Directors shall determine and (2) in voluntary and involuntary liquidation, to the amounts fixed for each series by the Board of Directors, plus in each case, unpaid accumulated dividends.

Voting Rights

Generally, only NW Natural’s common stock has voting rights. The common stock has cumulative voting rights with respect to the election of directors. The preferred stock shall have no right to vote in the election of directors or for any other purpose, except as may be otherwise provided by law or by resolutions establishing any series of preferred stock in accordance with NW Natural’s Amended and Restated Articles of Incorporation.

Dividend Limitations

Should dividends on the preferred stock be in arrears, no dividends on the common stock may be paid or declared.

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PLAN OF DISTRIBUTION

NW Natural may sell the securities offered pursuant to this prospectus and one or more prospectus supplements (Offered Securities), on a continuous or delayed basis, in one or more series: (1) through one or more underwriters or dealers; (2) through one or more agents; (3) directly to a single purchaser or a limited number of purchasers; (4) through a combination of any such methods of sale; or (5) through other methods described in the applicable prospectus supplement.

Through Underwriters or Dealers

If underwriters are used in the sale, the Offered Securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, at the initial public offering price or at varying prices determined at the time of the sale. The Offered Securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more managing underwriters. The underwriter or underwriters with respect to the Offered Securities will be named in the prospectus supplement relating to such offering and, if an underwriting syndicate is used, the managing underwriter or underwriters will be set forth on the cover page of such prospectus supplement. Unless otherwise set forth in such prospectus supplement, the obligations of the underwriters to purchase the Offered Securities offered by such prospectus supplement will be subject to certain conditions precedent, and the underwriters will be obligated to purchase all of such Offered Securities if any are purchased. If a dealer is used in the sale, the securities will be sold to the dealer as principal. The dealer may then resell those securities at varying prices determined at the time of resale.

Through Agents

The Offered Securities may be sold through agents designated by NW Natural from time to time. A prospectus supplement will set forth the name of any agent involved in the offer or sale of the Offered Securities in respect of which such prospectus supplement is delivered as well as any commissions payable by NW Natural to such agent. Unless otherwise indicated in such prospectus supplement, any such agent will be acting on a reasonable best efforts basis for the period of its appointment.

Directly to One or More Purchasers

NW Natural may sell the Offered Securities directly to one or more purchasers. In this case, no underwriters or agents would be involved.

General Information

The prospectus supplement with respect to the Offered Securities will set forth the terms of the offering of such Offered Securities, including:

Any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

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If so indicated in the prospectus supplement with respect to the Offered Securities, NW Natural may authorize agents, underwriters or dealers to solicit offers by certain specified institutions to purchase the Offered Securities from NW Natural at the initial public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. Such contracts will be subject to those conditions set forth in such prospectus supplement, and such prospectus supplement will set forth the commission payable for solicitation of such contracts.

The securities may also be offered and sold, if so indicated in the applicable prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more firms, which are referred to herein as the “remarketing firms,” acting as principals for their own accounts or as our agent, as applicable. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters, as that term is defined in the Securities Act, in connection with the securities remarketed thereby.

We may enter into derivative transactions with third parties or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of securities, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of securities. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be identified in the applicable prospectus supplement.

Agents, underwriters and dealers may be entitled under agreements entered into with NW Natural to indemnification by NW Natural against certain civil liabilities, including certain liabilities under the Securities Act or to contribution by NW Natural with respect to payments which such agents, underwriters and dealers may be required to make in respect thereof.

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EXPERTS

The financial statements and management’s assessment of the effectiveness of internal control over financial reporting (which is included in Management’s Report on Internal Control over Financial Reporting) incorporated in this Prospectus by reference to NW Natural’s Current Report on Form 8-K dated September 24, 2018 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

LEGALITY

The legality of the securities will be passed upon for NW Natural by MardiLyn Saathoff, Esquire, Senior Vice President, Regulation and General Counsel of NW Natural, and by Morgan, Lewis & Bockius LLP, New York, New York. Ms. Saathoff may rely upon the opinion of Morgan, Lewis & Bockius LLP as to certain legal matters arising under New York law. Morgan, Lewis & Bockius LLP may rely upon the opinion of Ms. Saathoff as to certain legal matters arising under Oregon law. Ms. Saathoff is regularly employed by NW Natural, participates in various employee benefit plans under which she may receive shares of common stock of NW Holdings and currently beneficially owns less than one percent of the outstanding shares of common stock of NW Holdings.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Northwest Natural Holding Company

The Oregon Business Corporation Act (Act) provides, in general, that a director or officer of a corporation who has been or is threatened to be made a defendant in a legal proceeding because that person is or was a director or officer of the corporation:

(1) shall be indemnified by the corporation for all expenses of such litigation when the director or officer is wholly successful on the merits or otherwise;

(2) may be indemnified by the corporation for the expenses, judgments, fines and amounts paid in settlement of such litigation (other than a derivative lawsuit) if he or she acted in good faith and in a manner reasonably believed to be in, or at least not opposed to, the best interests of the corporation (and, in the case of a criminal proceeding, had no reasonable cause to believe the conduct was unlawful); and

(3) may be indemnified by the corporation for expenses of a derivative lawsuit (a suit by a shareholder alleging a breach by a director or officer of a duty owed to the corporation) if he or she acted in good faith and in a manner reasonably believed to be in, or at least not opposed to, the best interests of the corporation, provided the director or officer is not adjudged liable to the corporation.

The Act also authorizes the advancement of litigation expenses to a director or officer upon receipt of a written affirmation of the director’s or officer’s good faith belief that the standard of conduct in Section (2) or (3) above has been met and an undertaking by such director or officer to repay such expenses if it is ultimately determined that he or she did not meet that standard and, therefore, is not entitled to be indemnified. The Act also provides that the indemnification provided thereunder shall not be deemed exclusive of any other rights to which those indemnified may be entitled under any bylaw, agreement, vote of shareholders or disinterested directors or otherwise.

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NW Holdings’ Amended and Restated Bylaws provide that NW Holdings shall indemnify directors and officers to the fullest extent permitted under the Act, thus making mandatory the discretionary indemnification authorized by the Act.

NW Holdings’ Amended and Restated Articles of Incorporation provide that NW Natural shall indemnify its officers and directors to the fullest extent permitted by law, which may be broader than the indemnification authorized by the Act.

NW Holdings has entered into indemnity agreements with its directors and officers which provide for indemnity to the fullest extent permitted by law and also alter or clarify the statutory indemnity in the following respects:

(1) prompt advancement of litigation expenses is provided if the director or officer makes the required affirmation and undertaking;

(2) the director or officer is permitted to enforce the indemnity obligation in court and the burden is on NW Holdings to prove that the director or officer is not entitled to indemnification;

(3) indemnity is explicitly provided for judgments and settlements in derivative actions;

(4) prompt indemnification is provided unless a determination is made that the director or officer is not entitled to indemnification; and

(5) partial indemnification is permitted if the director or officer is not entitled to full indemnification.

NW Holdings maintains in effect a policy of insurance providing for reimbursement to NW Holdings of payments made to directors and officers as indemnity for damages, judgments, settlements, costs and expenses incurred by them which NW Holdings may be required or permitted to make according to applicable law, common or statutory, or under provisions of its Amended and Restated Articles of Incorporation, Amended and Restated Bylaws or agreements effective under such laws.

Northwest Natural Gas Company

The Oregon Business Corporation Act (Act) provides, in general, that a director or officer of a corporation who has been or is threatened to be made a defendant in a legal proceeding because that person is or was a director or officer of the corporation:

(1) shall be indemnified by the corporation for all expenses of such litigation when the director or officer is wholly successful on the merits or otherwise;

(2) may be indemnified by the corporation for the expenses, judgments, fines and amounts paid in settlement of such litigation (other than a derivative lawsuit) if he or she acted in good faith and in a manner reasonably believed to be in, or at least not opposed to, the best interests of the corporation (and, in the case of a criminal proceeding, had no reasonable cause to believe the conduct was unlawful); and

(3) may be indemnified by the corporation for expenses of a derivative lawsuit (a suit by a shareholder alleging a breach by a director or officer of a duty owed to the corporation) if he or she acted in good faith and in a manner reasonably believed to be in, or at least not opposed to, the best interests of the corporation, provided the director or officer is not adjudged liable to the corporation.

The Act also authorizes the advancement of litigation expenses to a director or officer upon receipt of a written affirmation of the director’s or officer’s good faith belief that the standard of conduct in Section (2) or (3) above has been met and an undertaking by such director or officer to repay such expenses if it is ultimately determined that he or she did not meet that standard and, therefore, is not entitled to be indemnified. The Act also

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provides that the indemnification provided thereunder shall not be deemed exclusive of any other rights to which those indemnified may be entitled under any bylaw, agreement, vote of shareholders or disinterested directors or otherwise.

NW Natural’s Bylaws provide that NW Natural shall indemnify directors and officers to the fullest extent permitted under the Act, thus making mandatory the discretionary indemnification authorized by the Act.

NW Natural’s Amended and Restated Articles of Incorporation provide that NW Natural shall indemnify its officers and directors to the fullest extent permitted by law, which may be broader than the indemnification authorized by the Act.

NW Natural has entered into indemnity agreements with its directors and officers which provide for indemnity to the fullest extent permitted by law and also alter or clarify the statutory indemnity in the following respects:

(1) prompt advancement of litigation expenses is provided if the director or officer makes the required affirmation and undertaking;

(2) the director or officer is permitted to enforce the indemnity obligation in court and the burden is on NW Natural to prove that the director or officer is not entitled to indemnification;

(3) indemnity is explicitly provided for judgments and settlements in derivative actions;

(4) prompt indemnification is provided unless a determination is made that the director or officer is not entitled to indemnification; and

(5) partial indemnification is permitted if the director or officer is not entitled to full indemnification.

NW Natural maintains in effect a policy of insurance providing for reimbursement to NW Natural of payments made to directors and officers as indemnity for damages, judgments, settlements, costs and expenses incurred by them which NW Natural may be required or permitted to make according to applicable law, common or statutory, or under provisions of its Amended and Restated Articles of Incorporation, Bylaws or agreements effective under such laws.

Reference is made to the Exhibit Index immediately prior to the signature pages hereof.

Each of the undersigned registrants hereby undertakes:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

(6) That, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s Annual Report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(7) To file, if applicable, an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act of 1939 in accordance with the rules and regulations prescribed by the SEC under Section 305(b)(2) of the Trust Indenture Act of 1939.

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

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EXHIBIT INDEX

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POWER OF ATTORNEY

Each director and/or officer of the registrant whose signature appears hereinafter hereby appoints David H. Anderson, Frank H. Burkhartsmeyer, Brody J. Wilson, MardiLyn Saathoff, and Shawn M. Filippi as the Agents for Service named in this registration statement, and each of them severally, as his or her attorney-in-fact to sign in his or her name and behalf, in any and all capacities stated below, and to file with the Securities and Exchange Commission any and all amendments, including post-effective amendments, to this registration statement, and the registrant hereby also appoints each such Agent for Service as its attorney-in-fact with like authority to sign and file any such amendments in its name and behalf.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, Northwest Natural Holding Company certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Portland, and State of Oregon, on this 2nd day of October, 2018.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed below by the following persons in the capacities and on this 2nd day of October, 2018.

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POWER OF ATTORNEY

Each director and/or officer of the registrant whose signature appears hereinafter hereby appoints David H. Anderson, Frank H. Burkhartsmeyer, Brody J. Wilson, MardiLyn Saathoff, and Shawn M. Filippi as the Agents for Service named in this registration statement, and each of them severally, as his or her attorney-in-fact to sign in his or her name and behalf, in any and all capacities stated below, and to file with the Securities and Exchange Commission any and all amendments, including post-effective amendments, to this registration statement, and the registrant hereby also appoints each such Agent for Service as its attorney-in-fact with like authority to sign and file any such amendments in its name and behalf.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, Northwest Natural Gas Company certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Portland, and State of Oregon, on this 2nd day of October, 2018.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed below by the following persons in the capacities and on this 2nd day of October, 2018.

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