The forward sellers referred to below are offering $375,000,000 of shares of our common stock, no par value. We expect to enter into forward sale agreements with an affiliate of Barclays Capital Inc. and an affiliate of J.P. Morgan Securities LLC, which affiliates we refer to in such capacity as the “forward purchasers,” with respect to $375,000,000 of shares of our common stock. In connection with these forward sale agreements, the forward purchasers or their respective affiliates, whom we refer to in such capacity as the “forward sellers,” at our request, are borrowing from third parties and selling to the underwriters an aggregate of $375,000,000 of shares of our common stock. If the forward purchasers determine in good faith, after using commercially reasonable efforts, that the forward sellers are unable to borrow and deliver for sale to the underwriters on the anticipated closing date such number of shares of our common stock or that the forward sellers are unable to borrow, at a stock loan rate not greater than a specified rate, and deliver for sale to the underwriters on the anticipated closing date such number of shares of our common stock, or if the forward sellers elect not to borrow shares of our common stock and sell such shares to the underwriters because certain conditions in the underwriting agreement for this offering are not satisfied, then we will issue and sell to the underwriters a number of shares equal to the number of shares that the forward sellers do not borrow and sell to the underwriters, and under such circumstances the number of shares of our common stock underlying the relevant forward sale agreement will be decreased by the number of shares of our common stock that we issue and sell to the underwriters.

We will not initially receive any proceeds from the sale of our common stock sold by the forward sellers to the underwriters, except in certain circumstances described in this prospectus supplement. We expect to fully physically settle the forward sale agreements and receive proceeds, subject to certain adjustments, from the sale of those shares of common stock in one or more settlements on or prior to October 25, 2024 which is the scheduled final settlement date under the forward sale agreements. If we elect to cash settle all or a portion of the forward sale agreements, we may not receive any proceeds from such election, and we may owe cash to the forward purchasers. If we elect to net share settle all or a portion of the forward sale agreements, we will not receive any cash proceeds from such election, and we may owe shares of our common stock to the forward purchasers. See “Underwriting (Conflicts of Interest) – Forward Sale Agreements.”

As described under “Use of Proceeds,” we intend to allocate an amount equivalent to the net proceeds from this offering to finance, in whole or in part, one or more Eligible Investments (as defined herein). See “Summary Information” and “Use of Proceeds.”

Our common stock is listed on the New York Stock Exchange under the symbol “POR.” On October 24, 2022, the last reported sale price of our common stock on the New York Stock Exchange was $43.75 per share.

Investing in the shares involves risks. See the “Risk Factors” section on page S-15 of this prospectus supplement.

The underwriters have been granted the option, exercisable in whole or from time to time in part, to purchase up to an additional $56,250,000 of shares of our common stock, at the public offering price per share shown above, less the underwriting discount and subject to possible adjustment as described under “Underwriting (Conflicts of Interest),” exercisable for 30 days after the date of this prospectus supplement. Upon any exercise of such option, we expect to enter into additional forward sale agreements with each of the forward purchasers in respect of the number of shares sold to the underwriters by the applicable forward purchaser or its affiliate in connection with the exercise of such option. Unless the context requires otherwise, the term “forward sale agreement” as used in this prospectus supplement includes any additional forward sale agreement that we enter into in connection with the exercise by the underwriters of their option to purchase additional shares. In such event, if the forward purchasers determine in good faith, after using commercially reasonable efforts, that the forward sellers are unable to borrow and deliver for sale to the underwriters on the anticipated closing date for the exercise of such option the number of shares of our common stock in respect of which such option has been exercised or that the forward sellers are unable to borrow, at a stock loan rate not greater than a specified rate, and deliver for sale to the underwriters on the anticipated closing date for the exercise of such option the number of shares of our common stock in respect of which such option has been exercised, or if the forward sellers elect, in connection with the exercise of such option, not to borrow shares of our common stock and sell such shares to the underwriters because certain conditions in the underwriting agreement for this offering are not satisfied, we will issue and sell directly to the underwriters the number of shares of our common stock not delivered and sold by such forward purchaser or its affiliate to the underwriters, and under such circumstances the number of shares of our common stock underlying the relevant additional forward sale agreement will be decreased by the number of shares of our common stock that we issue and sell to the underwriters. Upon any exercise of such option, if we do not enter into additional forward sale agreements with the forward purchasers, we will issue and sell to the underwriters the number of shares of our common stock in respect of which such option has been exercised.

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

The underwriters expect to deliver the shares of common stock to purchasers on or about,    , 2022.

This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of the offering of our common stock and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference in the accompanying prospectus. The second part is the accompanying prospectus, which gives more general information, some of which does not apply to our common stock. If the description of our common stock or the offering of our common stock varies between this prospectus supplement and the accompanying prospectus, you should rely on the information in this prospectus supplement.

We have not, and the underwriters have not, authorized anyone to provide you with different information other than the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any related free writing prospectus issued by us. If anyone provides you with different or inconsistent information, we cannot assure you as to its accuracy. We are offering to sell our common stock and seeking offers to buy our common stock only in jurisdictions where offers and sales are permitted. You should assume that the information contained in this prospectus supplement, the accompanying prospectus and any such free writing prospectus is accurate only as of their respective dates and the information contained in documents incorporated by reference is accurate only as of the respective dates of those documents, in each case regardless of the time of delivery of this prospectus supplement or the accompanying prospectus or any such free writing prospectus or any sale of our common stock. Our business, financial condition, results of operations and prospects may have changed since those dates.

The distribution of this prospectus supplement, the accompanying prospectus and any related free writing prospectus filed with the U.S. Securities and Exchange Commission (the “SEC”) and the offering of our common stock in certain jurisdictions may be restricted by law. Persons into whose possession this prospectus supplement, the accompanying prospectus and any such free writing prospectus come should inform themselves about and observe any such restrictions. This prospectus supplement, the accompanying prospectus and any such free writing prospectus do not constitute, and may not be used in connection with, an offer or solicitation by anyone in any jurisdiction in which such offer or solicitation is not authorized or in which the person making such offer or solicitation is not qualified to do so or to any person to whom it is unlawful to make such offer or solicitation. See “Underwriting (Conflicts of Interest).”

In this prospectus supplement, unless otherwise expressly stated or the context requires otherwise:

Unless otherwise specified or the context requires otherwise, information in this prospectus supplement assumes that (1) we do not sell any shares of common stock to the underwriters in lieu of shares that would otherwise have been sold by the forward seller, (2) the option to the underwriters has been granted in this offering to purchase additional shares of our common stock is not exercised, and (3) we effect full physical settlement of the forward sale agreements that we enter into in connection with this offering.

This prospectus supplement, the accompanying prospectus and the documents they incorporate by reference contain, and any related free writing prospectus issued by us may contain, statements that are not historical facts and constitute “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements include, but are not limited to, statements that relate to expectations, beliefs, plans, assumptions, and objectives concerning future results of operations, business prospects, loads, outcome of litigation and regulatory proceedings, capital expenditures, market conditions, the performance of our Eligible Investments with respect to various measures of sustainability, future events or performance, and other matters. Words or phrases such as “anticipates,” “believes,” “estimates,” “expects,” “intends,” “plans,” “predicts,” “projects,” “will likely result,” “will continue,” “should,” or similar expressions are intended to identify forward-looking statements.

Forward-looking statements are not guarantees of future performance and involve risks and uncertainties, including those risks discussed in this prospectus supplement, the accompanying prospectus and the documents they incorporate by reference, that could cause actual results or outcomes to differ materially from those expressed. Expectations, beliefs and projections of PGE are expressed in good faith and are believed by the Company to have a reasonable basis including, but not limited to, management’s examination of historical operating trends and data contained either in internal records or available from third parties, but there can be no assurance that PGE’s expectations, beliefs or projections will be achieved or accomplished.

In addition to any assumptions and other factors and matters referred to specifically in connection with forward-looking statements, factors that could cause actual results or outcomes for PGE to differ materially from those discussed in such forward-looking statements include:

While we believe that the assumptions underlying such forward-looking statements are reasonable, there can be no assurance that future events or developments will not cause such statements to be inaccurate. Any forward-looking statement speaks only as of the date on which such statement is made and, except as required by law, PGE undertakes no obligation to update any forward-looking statement to reflect events or circumstances after the date on which such statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time and it is not possible for management to predict all such factors or assess the impact of any such factor on the business or the extent to which any factor, or combination of factors, may cause results to differ materially from those contained in any forward-looking statement. All forward-looking statements contained in this prospectus supplement, the accompanying prospectus and the documents they incorporate by reference are qualified in their entirety by this cautionary statement. We expressly disclaim any obligation or undertaking to update or revise any forward-looking statements to reflect any changes in events or circumstances or in our expectations or results.

We caution you not to rely unduly on any forward-looking statements. You should review and consider carefully the risks, uncertainties and other factors that affect our business as described herein and in our reports and other documents on file with the SEC that are incorporated by reference into this prospectus supplement and the accompanying prospectus and any related free writing prospectus issued by us. You may obtain copies of these reports and documents as described under “Where You Can Find More Information”.

This prospectus supplement, the accompanying prospectus and the documents incorporated and deemed to be incorporated by reference in the accompanying prospectus include, and any free writing prospectus we provide you in connection with this offering may include, market, demographic and industry data and forecasts that are based on or derived from sources such as independent industry publications, publicly available information, government data and other information from third parties or that have been compiled or prepared by our management or employees. We do not guarantee the accuracy or completeness of any of this information, and we have not independently verified any of the information provided by third party sources. In addition, market, demographic and industry data and forecasts involve estimates, assumptions and other uncertainties and are subject to change based on various factors, including those discussed under the heading “Risk Factors” in this prospectus supplement and under similar headings in documents that are incorporated or deemed to be incorporated by reference in the accompanying prospectus. Accordingly, you should not place undue reliance on any of this information.

Investment in our common stock involves risks. You should carefully consider the risks described below and the risk factors incorporated into this prospectus supplement and the accompanying prospectus by reference to our most recent Annual Report on Form 10-K, our subsequent Quarterly Reports on Form 10-Q and any Current Reports on Form 8-K filed (and not furnished) by us with the SEC subsequent to the last day of the fiscal year covered by our most recent Annual Report on Form 10-K and all other information contained or incorporated by reference into this prospectus supplement and the accompanying prospectus, as updated by our subsequent filings under the Securities Exchange Act of 1934, as amended, as well as any free writing prospectus we may provide you in connection with this offering, before acquiring any of our common stock. The occurrence of any of these risks might cause you to lose all or part of your investment in the shares. See also “Cautionary Note Regarding Forward-Looking Statements.” In that regard, unless otherwise expressly stated or the context otherwise requires, references to our common stock or preferred stock appearing under the caption “Risk Factors” in our most recent Annual Report on Form 10-K include the common stock offered hereby.

The market price for our common stock has historically experienced, and may continue to experience, volatility. This volatility may affect the price at which you could sell our common stock, and the sale or issuance of substantial amounts of our common stock, or the perception that such sales or issuances could occur, could adversely affect the market price of our common stock. In addition, the availability for sale of substantial amounts of our common stock could adversely impact its market price. Likewise, the forward sale agreements that we plan to enter into in connection with this offering, or the expectation that those issuances will occur, may have a similar effect. Any of the foregoing may also impair our ability to raise additional capital through the sale of our equity securities. The market price of our common stock may be influenced by many factors, some of which are beyond our control, including the factors discussed above under “Cautionary Note Regarding Forward-Looking Statements” or elsewhere in this Risk Factors section and the following:

We intend to allocate an amount equivalent to the net proceeds from this offering that we receive to one or more Eligible Investments, which may include the financing or refinancing of such projects, as described under “Use of Proceeds” in this prospectus supplement. Pending the allocation of the net proceeds from this offering to

Eligible Investments, we will manage any portion of the net proceeds that we receive, but have not yet been allocated to Eligible Investments in accordance with our normal liquidity management practices. We intend to complete the allocation of an amount equivalent to the net proceeds of the offering to Eligible Investments within five years.

There can be no assurance that the Eligible Investments to which we may allocate any net proceeds from this offering will meet investor criteria and expectations regarding environmental impact and sustainability performance. In particular, no assurance is given that any such Eligible Investments will satisfy, whether in whole or in part, any present or future investor expectations or requirements in regards to any investment criteria or guidelines with which such investor or its investments are required to comply, whether by any present or future applicable law or regulations or by their own bylaws or other governing rules or investment portfolio mandates (in particular with regard to any direct or indirect environmental, sustainability or social impact of the Eligible Investments). Adverse environmental or social impacts may occur during the design, construction and operation of the projects or the projects may become controversial or criticized by activist groups or other stakeholders.

Furthermore, this offering does not create or represent a class of shares separate from the Company’s existing shares of common stock, and as such, the shares issued will trade with the same CUSIP as existing shares. As a result, there will be no differentiation between shares issued as part of this offering and the Company’s existing shares, and investors may not have a reliable method for indicating whether shares held were issued in this offering.

While we intend to allocate an amount equivalent to the net proceeds from this offering that we receive to one or more Eligible Investments in the manner described under “Use of Proceeds”, there is no requirement, contractual or otherwise, for us to do so. There can be no assurance that the relevant projects or uses that are the subject of, or related to, any Eligible Investments will be capable of being implemented in or substantially in such manner or in accordance with any timing schedule and that accordingly an amount equal to such proceeds will be totally or partially allocated to such Eligible Investments. There can also be no assurance that such Eligible Investments will lead to the results or outcomes (whether or not related to environmental or broader sustainability issues) originally anticipated by us. We cannot assure you that we will allocate amounts relating to this offering to Eligible Investments or meet or continue to meet the investment requirements or aspirations of certain sustainability focused investors. Furthermore, unlike certain sustainability-linked and/or green bond offerings in which the interest rate on the related security may increase if the proceeds are not used for eligible projects, there will be no such monetary consequence if we do not allocate an amount equivalent to the net proceeds from this offering to Eligible Investments.

There is currently no clearly defined definition (legal, regulatory or otherwise) of, nor market consensus as to what constitutes, a “green,” “social,” “sustainable” or an equivalently labeled project, or as to what precise attributes are required for a particular project to be defined as “green,” “social,” “sustainable” or such other equivalent label, nor can any assurance be given that such a clear definition or consensus will develop over time. Accordingly, no assurance is or can be given to investors that any Eligible Investments we select to receive an allocation of net proceeds from this offering will meet any or all investor expectations regarding such “green,” “social,” “sustainable” or other equivalently-labeled performance objectives, or that adverse environmental, social and/or other impacts will not occur during the implementation or construction of any Eligible Investments to which we allocate net proceeds from this offering.

No assurance or representation is given as to the suitability or reliability for any purpose whatsoever of any opinion or certification of any third party (whether or not solicited by us) that may be made available in connection with this offering, and, in particular, with respect to whether or not our Eligible Investments, our

allocation of an amount equivalent to the net proceeds from this offering to Eligible Investments or the reporting and other procedures described under the caption “Use of Proceeds” in this prospectus supplement meet or will meet any green, sustainability, social and/or similar guidelines, principles or other criteria or requirements. For the avoidance of doubt, no such opinion or certification is, nor shall any such opinion or certification be deemed to be, incorporated by reference into this prospectus supplement, the accompanying prospectus or the related registration statement or to form a part of this prospectus supplement, the accompanying prospectus or the related registration statement. No such opinion or certification is, nor shall any such opinion or certification be deemed to be, a recommendation by us, any underwriter or any other person to buy, sell or hold shares of our common stock. Any such opinion or certification is only current as of the date that opinion or certification was initially issued. Prospective investors must determine for themselves the relevance of any such opinion or certification or the information contained therein or the provider of such opinion or certification. Any withdrawal of any such opinion or certification or any additional opinion or certification attesting that we are not complying in whole or in part with any matters for which such opinion or certification is opining or certifying may result in adverse consequences for certain investors with mandates to invest in securities to be used for a particular purpose.

We expect that we will need to raise additional capital in the future. We may raise additional funds through public or private equity or debt offerings or other financings, as well as additional borrowings under our credit facilities. Additional issuances of equity securities, including shares of our common stock, or debt or other securities that are convertible into or exchangeable for, or that represent the right to receive, common stock could dilute the economic and other rights and interests of holders of shares of our common stock and cause the market price of our common stock to decline.

Any new debt financing we enter into may involve covenants that restrict our operations more than our current outstanding debt and credit facilities. These restrictive covenants could include limitations on additional borrowings, and specific restrictions on the use of our assets, as well as prohibitions or limitations on our ability to create liens, pay dividends, receive distributions from our subsidiaries, redeem or repurchase our stock or make investments. These factors could hinder our access to capital markets and limit or delay our ability to carry out our capital expenditure plan or pursue other opportunities beyond the current capital expenditure plan, including the development opportunities that are part of our projects described above under “Summary Information – Recent Developments – OPUC.”

We have historically paid regular quarterly dividends on our common stock. However, the declaration of dividends is at the discretion of our board of directors and is not guaranteed. Any future payments of cash dividends, and the amount of any cash dividends we pay, on our common stock and any series of our preferred stock we may issue in the future will depend on, among other things, our financial condition, capital requirements and results of operations, and the ability of our subsidiaries and investments to distribute cash to us, as well as other factors that our board of directors may consider relevant. If we were to reduce the amount of cash dividends per share payable on our common stock, fail to increase the amount of those cash dividends per share in the future in accordance with market expectations, or at all, or cease paying those cash dividends altogether, it would likely have an adverse impact, which may be material, on the market price of our common stock and any series of preferred stock we may issue in the future.

In addition, the terms of our debt instruments may limit our payment of dividends. Under our Indenture of Mortgage and Deed of Trust, dated July 1, 1945, as amended and supplemented to date, between Portland General Electric Company and Wells Fargo Bank, National Association (successor trustee to HSBC Bank USA, National Association), so long as any of our first mortgage bonds are outstanding, we may not pay or declare dividends (other than stock dividends) on common stock or purchase or retire for a consideration (other than in exchange for other shares of our capital stock or the proceeds from the sale of other shares of our capital stock) any shares of capital stock of any class, if the aggregate amount distributed or expended after December 31, 1944 would exceed the aggregate amount of our net income, as adjusted, available for dividends on our common

stock accumulated after December 31, 1944. At December 31, 2021, approximately $398 million of accumulated net income was available for payment of dividends under this provision.

Further, under Oregon law, our board of directors may not declare and pay dividends on shares of our common stock or any series of preferred stock we may issue unless after giving effect to such dividend, in the judgment of our board of directors: (a) we would be able to pay our debts as they become due in the usual course of business; and (b) our total assets would at least equal the sum of our total liabilities plus the amount that would be needed if we were to be dissolved at the time of the distribution, to satisfy the preferential rights upon dissolution of shareholders whose preferential rights are superior to those receiving the distribution. Further, even if we are permitted under our contractual obligations and Oregon law to declare and pay cash dividends on the shares of common stock and any series of preferred stock we may issue, we may not have sufficient cash to declare and pay dividends in cash on the outstanding shares of our common stock and any series of preferred stock we may issue.

We are a “public utility” (as defined in the Federal Power Act (the “FPA”)) subject to the jurisdiction of the Federal Energy Regulatory Commission (“FERC”) because we own or operate a FERC-jurisdictional facility, including transmission facilities, certain generation interconnection facilities, and various “paper” facilities, such as wholesale power sales contracts and market-based rate tariffs. The FPA requires us either to obtain prior authorization from FERC prior to the transfer of an amount of our common stock sufficient to convey direct or indirect “control” over us or to qualify for a blanket authorization granted under FERC’s regulations for certain types of transfers generally deemed by FERC not to convey direct or indirect “control.” At the same time, if any person and any of its associate or affiliate companies in the aggregate, any “public utility” (as defined in the FPA), or any “holding company” (as defined in the Public Utility Holding Company Act of 2005) acquires an amount of our common stock sufficient to convey direct or indirect “control” over us, that acquirer would either need to obtain prior authorization for such acquisition from FERC or to qualify for a blanket authorization under FERC’s regulations. Under FERC’s regulations and applicable precedent, ownership of 10% or more of our common stock would be presumed to give that owner “control” absent rebuttal of that presumption. Any failure to obtain any such prior authorization or to qualify for a blanket authorization would generally allow FERC to void the transaction that resulted in the relevant person obtaining “control” over us, including by acquiring 10% or more of our common stock, and/or to assess monetary penalties. Accordingly, investors should consult their own legal advisors before acquiring shares of common stock in this offering if the acquisition of these shares would result in their owning more than 10% of our outstanding common stock or would otherwise give them direct or indirect control over us.

We are incorporated under the laws of the State of Oregon. The Oregon Business Combination Act imposes some restrictions on mergers and other business combinations between us and holders of 15% or more of our outstanding common stock. In addition, we are subject to the anti-takeover provisions of the Oregon Control Share Act, which would prohibit an acquirer, under certain circumstances, from voting shares of our stock after crossing specific threshold ownership percentages, unless the acquirer obtains the approval of our shareholders or we amend our articles of incorporation or bylaws to opt-out of the Oregon Control Share Act.

Other statutory and regulatory factors may also limit another party’s ability to acquire us. Section 757.511 of the Oregon Revised Statutes provides that no person, directly or indirectly, may acquire power to exercise any substantial influence over the policies and actions of a public utility without the prior approval of the OPUC if such person is or would become an “affiliated interest” (as defined in Section 757.015 (1), (2) or (3) of the Oregon Business Corporation Act), which includes a person that directly or indirectly holds 5% or more of the voting securities of the public utility. The regulatory approval process for an acquirer could be lengthy and the outcome uncertain, which may deter otherwise interested parties from proposing or attempting a business combination with us and result in a limited number of potential acquirers. In addition, under the Oregon Community Power Act, in the event of a proposed sale of more than 50% of our voting shares, an acquisition

review committee will be formed to represent that cities and counties that would be affected by the acquisition. Such committee would then evaluate whether it would be in the best interests of the public for Oregon Community Power, a public corporation formed under the Oregon Community Power Act, to instead acquire us. In the event that such committee reached such determination, the Governor of the State of Oregon would then activate Oregon Community Power, which would then be empowered to complete such acquisition. These statutory provisions may discourage or limit another party’s ability to acquire us and could deprive you of the opportunity to gain a takeover premium for shares of our common stock. For more information, please read the section entitled “Description of Common Stock—Provisions With Possible Anti-Takeover Effects” beginning on page 7 of the accompanying prospectus.

Certain provisions of our articles of incorporation and bylaws could have the effect of delaying, deterring or preventing another party from acquiring or seeking to acquire control of us. These provisions are intended to discourage certain types of coercive takeover practices and inadequate takeover bids and to encourage anyone seeking to acquire control of us to negotiate first with our board of directors. However, these provisions could also delay, deter or prevent a change of control or other takeover of our company that our shareholders might consider to be in their best interests, including transactions that might result in a premium being paid over the market prices of our common stock and may also limit the prices that investors are willing to pay in the future for our common stock.

These provisions may also have the effect of preventing changes in our management. Our articles of incorporation and bylaws include anti-takeover provisions that:

Credit rating agencies routinely evaluate us, and their ratings of our long-term and short-term debt are based on a number of factors, including the perceived supportiveness of the regulatory environment affecting our utility operations, our cash generating capability, level of indebtedness, overall financial strength, the status of certain capital projects, and indebtedness, as well as factors beyond our control, such as tax reform, the state of the economy and our industry generally. We have incorporated by reference in this prospectus supplement and the accompanying prospectus the risk factor included in our most recent Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC on February 17, 2022 (the “2022 Form 10-K”) under the heading “Risk Factors – Economic, Financial, and Market Risks – Adverse changes in PGE’s credit ratings could negatively affect its access to the capital markets and its cost of borrowed funds.” You should review and consider carefully the risks, uncertainties and other factors related to our credit ratings included in such risk factor and elsewhere in our 2022 Form 10-K as well as those risks, uncertainties and other factors related to our credit ratings described below.

We cannot assure you that one or more credit rating agencies will not downgrade our credit ratings or that additional credit rating agencies will not place those ratings on negative outlook, either in the near term or later.

On October 25, 2022, we announced that our board of directors approved a plan to construct the Clearwater Wind Project for approximately $415 million, excluding AFUDC, and we will need to make additional acquisitions of renewable and non-emitting resources to meet our requirement under Oregon House Bill 2021 by 2030. The completion of the construction of Clearwater Wind Project will be dependent upon a number of factors that may be beyond our control, including, but not limited to, that a condition to closing of such acquisition may not be satisfied and the risk that such acquisition may not be completed for other reasons, or may not be completed on the terms or timing currently contemplated. In addition, even if completed, there can be no assurance that the construction of the Clearwater Wind Project will result in the anticipated benefits or that such acquisition would result in additional value to our shareholders.

Sales or issuances of substantial amounts of our common stock in the public market, including upon settlement of the forward sale agreements we plan to enter into in connection with this offering, or the perception that these sales or issuances may occur, could cause the market price of our common stock to decline. This could also impair our ability to raise additional capital through the sale of our equity securities. Future sales or issuances of our common stock or other equity-related securities could be dilutive to holders of our common stock and could adversely affect their voting and other rights and economic interests, including purchasers of our common stock in this offering.

If any forward purchaser or its affiliate does not deliver and sell all of the shares of our common stock to be delivered and sold by it pursuant to the terms of the underwriting agreement (including because insufficient shares of our common stock were made available by securities lenders for borrowing at a stock borrow cost below a specified threshold), we will issue and sell directly to the underwriters the number of shares of our common stock not delivered and sold by the relevant forward purchaser or its affiliate, and under such circumstances the number of shares of our common stock underlying such forward sale agreement will be decreased by the number of shares of our common stock that we issue and sell to the underwriters. The stock loan market is volatile, and it is uncertain whether sufficient shares of our common stock will be made available to borrow prior to closing.

Each forward purchaser will have the right to accelerate its respective forward sale agreement (or, in certain cases, the portion thereof that it determines is affected by the relevant event) and require us to physically settle the applicable forward sale agreement on a date specified by the applicable forward purchasers if (1) in its commercially reasonable judgment, (a) it or its affiliate is unable to hedge (or maintain a hedge of) its exposure in a commercially reasonable manner under such forward sale agreement because insufficient shares of our common stock have been made available for borrowing by securities lenders or (b) it or its affiliates would incur a stock borrow cost in excess of a specified threshold; (2) we declare any dividend, issue or distribution on shares of our common stock that is payable in (a) cash in excess of specified amounts (unless it constitutes an extraordinary dividend under the forward sale agreement), (b) securities of another company that we acquire or own (directly or indirectly) as a result of a spin-off or similar transaction, or (c) any other type of securities (other than our common stock), rights, warrants or other assets for payment at less than the prevailing market price; (3) certain ownership thresholds applicable to such forward purchaser and its affiliates are or would be exceeded; (4) an event (a) is announced that if consummated would result in certain mergers or tender offers, as well as certain events involving our nationalization, our insolvency or a delisting of our common stock or (b) occurs that would constitute a hedging disruption or a change in law; or (5) certain other events of default or termination events occur, including, among others, any material misrepresentation made by us in connection with such forward sale agreement (each as more fully described in the relevant forward sale agreement).

A forward purchaser’s decision to exercise its right to accelerate its respective forward sale agreement (or, in certain cases, the portion thereof that it determines is affected by the relevant event) and to require us to settle such forward sale agreement will be made irrespective of our interests, including our need for capital. In such cases, we could be required to issue and deliver our common stock under the terms of the physical settlement provisions of the relevant forward sale agreement irrespective of our capital needs, which would result in dilution

to our earnings per share and may adversely affect the market price of our common stock. In addition, we would be obligated to issue some or all of the shares offered hereby pursuant to the underwriting agreement in the event that the number of shares underlying the forward sale agreements is reduced, as described in “Underwriting (Conflicts of Interest) – Forward Sale Agreements.”

The forward sale agreements provide for settlement on a settlement date or dates to be specified at our discretion, but which we expect to occur in one or more settlements on or prior to October 25, 2024. Subject to the provisions of the forward sale agreements, delivery of our shares upon physical or net share settlement of the forward sale agreements will result in dilution to our earnings per share and may adversely affect the market price of our common stock.

We may elect, subject to certain conditions, cash settlement or net share settlement for all or a portion of our obligations under the forward sale agreements if we conclude that it is in our interest to do so. For example, we may conclude that it is in our interest to cash settle or net share settle some or all of the forward sale agreements if we have no current use for all or a portion of the net proceeds due upon physical settlement of the forward sale agreements.

If we elect to cash or net share settle all or a portion of the shares of our common stock underlying any forward sale agreements, we would expect the applicable forward purchasers or their respective affiliates to purchase the number of shares necessary, based on the number of shares with respect to which we have elected cash or net share settlement, in order to satisfy their obligation to return shares of our common stock to securities lenders to unwind such forward purchaser’s hedge (after taking into consideration any shares of our common stock to be delivered by us to such forward purchaser, in the case of net share settlement); and, if applicable in connection with net share settlement, to deliver shares of our common stock to us or taking into account shares of our common stock to be delivered by us, as applicable. If the Rule 10b-18 volume weighted average price over the relevant unwind period (in the case of cash settlement) or the price paid by the applicable forward purchasers or their respective affiliates to so purchase our common stock (in the case of net share settlement), in each case, is above the applicable forward sale price at that time, we will pay or deliver, as the case may be, to the applicable forward purchasers under the applicable forward sale agreements, an amount in cash, or a number of shares of our common stock with a market value, equal to such difference. Any such difference could be significant. Conversely, if the Rule 10b-18 volume weighted average price over the relevant unwind period (in the case of cash settlement) or the price paid by the applicable forward purchasers or their respective affiliates to so purchase our common stock (in the case of net share settlement), in each case, is below the applicable forward sale price at that time, the applicable forward purchasers will pay or deliver, as the case may be, to us under the applicable forward sale agreements, an amount in cash, or a number of shares of our common stock with a market value, equal to such difference. See “Underwriting (Conflicts of Interest) – Forward Sale Agreements” for information on the forward sale agreements we plan to enter into in connection with this offering.

In addition, the purchase of our common stock by forward purchasers or their respective affiliates, to unwind the forward purchasers’ hedge position, could cause the price of our common stock to increase over time, thereby increasing the amount of cash or the number of shares of our common stock that we would owe to the applicable forward purchasers upon cash settlement or net share settlement, as the case may be, of the applicable forward sale agreements, or decreasing the amount of cash or the number of shares of our common stock that the applicable forward purchasers owe us upon cash settlement or net share settlement, as the case may be, of the applicable forward sale agreements.

If we file for or a regulatory authority with jurisdiction over us institutes, or we consent to, a proceeding seeking a judgment in bankruptcy or insolvency or any other relief under any bankruptcy or insolvency law or other similar law affecting creditors’ rights, or we or a regulatory authority with jurisdiction over us presents a petition for our winding-up or liquidation, and we consent to such a petition, the forward sale agreements will automatically terminate. If the forward sale agreements so terminate, we would not be obligated to deliver to the applicable forward purchasers any shares of our common stock not previously delivered, and the forward purchasers would be discharged from their obligation to pay the relevant forward sale price per share in respect of any shares of common stock not previously settled. Therefore, to the extent there are any shares of our common stock with respect to which the forward sale agreements have not been settled at the time of the commencement of any such bankruptcy or insolvency proceedings, we would not receive the relevant forward sale price per share in respect of those shares of common stock.

We will not initially receive any proceeds from the sale of shares of our common stock offered in this offering, unless an event occurs that requires us to sell such shares to the underwriters in lieu of the forward sellers selling such shares to the underwriters.

The forward sale price will initially be $   per share, which is equal to the public offering price per share of our common stock less the underwriting discount in this offering. The forward sale price is subject to adjustment pursuant to the forward sale agreements, and the actual proceeds are subject to settlement of the forward sale agreements. If the overnight bank funding rate decreases substantially prior to the settlement of the forward sale agreements, we may receive less than the initial forward sale price per share upon physical settlement of the forward sale agreements. Although we expect to settle the forward sale agreements entirely by the physical delivery of shares of our common stock in exchange for cash proceeds, we may elect cash settlement or net share settlement for all or a portion of our obligations under the forward sale agreements. If we elect to cash settle the forward sale agreements, we would expect to receive an amount of net proceeds that is significantly lower than the estimate included under this caption, and we may not receive any net proceeds (or may owe cash, which could be a significant amount, to the forward purchasers). If we elect to net share settle the forward sale agreements in full, we would not receive any cash proceeds from the forward purchasers (and we may be required to deliver shares of our common stock to the forward purchasers and the number of those shares could be significant). As a result, the actual amount of cash we receive upon settlement of the forward sale agreements may be less, perhaps substantially, than the amount reflected in this prospectus supplement or we may not receive any cash from that settlement. The forward sale agreements are subject to acceleration by the forward purchasers upon the occurrence of certain events.

The amount of cash or shares of our common stock we receive upon settlement of the forward sale agreements, if any, will depend on the relevant settlement method, the time of settlement, market interest rates and, if applicable under cash or net share settlement, the market price of our common stock during the period in which a forward counterparty unwinds its hedge positions with respect to the forward sale agreements. Settlement will occur on or prior to one or more dates specified by us under the forward sale agreements. We expect to settle the forward sale agreements in one or more settlements on or prior to October 25, 2024, which is the scheduled final settlement date under the forward sale agreements. See “Underwriting (Conflicts of Interest) – Forward Sale Agreements” for a description of certain terms of the forward sale agreements. We expect to use approximately $260 million of the net proceeds that we receive upon settlement of the forward sale agreements we plan to enter into in connection with this offering to repay our Term Loan.

We intend to allocate an amount equivalent to the net proceeds that we receive from the sale of shares of our common stock pursuant to the forward sale agreements and, if required under the limited circumstances described herein, from our sale of shares of our common stock directly to the underwriters in lieu of shares that would otherwise have been sold by the forward sellers, to finance, in whole or in part, one or more eligible green investments (“Eligible Investments”) as defined in our Green Financing Framework (as if the proceeds of this offering were from a bond offering as set forth in the Green Financing Framework) and detailed below. Pending allocation, we will manage any portion of the net proceeds that we receive, but have not yet been allocated to Eligible Investments in accordance with our normal liquidity management practices. We intend to complete the allocation of an amount equal to the net proceeds of the offering to Eligible Investments within five years.

Our Eligible Investments and the process by which we intend to select projects, manage proceeds, and report on allocation and impact will be aligned with our Green Financing Framework, detailed below.

Renewable Energy: Investments in or expenditures related to the acquisition, development, operation, and maintenance of new and existing renewable energy generation. Examples include wind and solar energy generation, battery storage, as well as all related transmission and distribution infrastructure.

Energy Efficiency: Investments in or expenditures related to advanced metering and grid infrastructure, energy efficient infrastructure, technology to enable customers to better manage their energy use, and expenditures in programs and technology that provide clean energy resource options for customers.

Clean Transportation: Investments in or expenditures related to transportation electrification activities.

Climate Change Adaptation: Investments in or expenditures related to helping to mitigate weather-related damage from elevated wildfire risk and enhancing the resilience of the grid.

As described in the Green Financing Framework, we will not knowingly allocate the proceeds of this offering to:

Our Treasury Department will be responsible for evaluating and selecting Eligible Investments in collaboration with internal subject matter experts from other departments (including Accounting, Financial Planning & Analysis, Investor Relations and Legal). Eligible Investments will be evaluated based on financial and risk-based analyses as well as strategic considerations to determine prioritization.

Our allocation of any net proceeds received will be reflected in internal records. Our Treasury Department will establish and maintain a register to record allocation of the net proceeds to Eligible Investments on an ongoing basis. In the case of divestment or if an Eligible Investment no longer meets the eligibility criteria listed above within five years of this offering, we intend to use reasonable efforts to reallocate the proceeds to one or more other Eligible Investments as soon as practicable.

We will publish a Green Use of Proceeds Equity Report on our dedicated Green Financing webpage following the one-year anniversary of the issuance and will update it annually until the net proceeds of the offering have been fully allocated.

The report is expected to include:

We expect each Green Use of Proceeds Equity Report will be accompanied by an attestation from an independent registered public accounting firm with respect to such firm’s examination of the assertion by our management team as to the aggregate amount of net proceeds allocated to specific categories of Eligible Investments. Examination will be conducted in accordance with attestation standards established by the American Institute of Certified Public Accountants.

The following table sets forth our consolidated cash and cash equivalents and capitalization as of September 30, 2022:

The following information is based on the assumptions described below and does not purport to reflect the actual amounts of proceeds we will receive from the settlement of the forward sale agreements or what our actual consolidated cash and cash equivalents or capitalization will be upon completion of those transactions. This table should be read in conjunction with our consolidated financial statements and related notes incorporated by reference in this prospectus supplement and the accompanying prospectus.

The information in the table does not reflect PGE’s expected $415 million investment in the Clearwater Wind Project. See “Summary Information-Recent Developments.”

The information in the foregoing table is based on the number of shares of our common stock outstanding as of September 30, 2022 with certain exclusions as described below, and assumes that we receive proceeds of $375.0 million from the sale of shares of our common stock pursuant to the forward sale agreements (before deducting fees, expenses and discounts and assuming full physical settlement of the forward sale agreements). The number of outstanding shares of our common stock as adjusted for the full physical settlement of the forward sale agreements appearing in the table above assumes that we will receive total proceeds of $375.0 million from the sale of shares of our common stock pursuant to the forward sale agreements and that the forward sale price will be $   per share of our common stock, which is equal to the last reported sale price of our common stock on the New York Stock Exchange appearing on the cover page of this prospectus supplement (in each case before deducting discounts and expenses).

The assumed amount of net proceeds from sales of our common stock under the forward sale agreements assumes full physical settlement of the forward sale agreements and that settlement under the forward sale agreements occurs concurrently with the closing of this offering. However, we expect to settle the forward sale agreements in one or more settlements on or prior to October 25, 2024. In addition, although we expect to settle the forward sale agreements entirely by the physical delivery of shares of our common stock in exchange for cash proceeds, we may elect cash settlement or net share settlement for all or a portion of our obligations under the forward sale agreements. If we elect to cash settle the forward sale agreements, we would expect to receive an amount of proceeds that is significantly lower than the amount reflected in the foregoing table, and we may

not receive any proceeds (or may owe cash, which could be a significant amount, to the forward purchasers). If we elect to net share settle the forward sale agreements in full, we would not receive any cash proceeds from the forward purchasers (and we may be required to deliver shares of our common stock to the forward purchasers, and the number of those shares could be significant). In addition, the forward sale price is subject to adjustment pursuant to the forward sale agreements and the actual proceeds are subject to settlement of the forward sale agreements. The forward sale agreements are also subject to acceleration by the forward purchasers upon the occurrence of certain events.

The actual number of shares of our common stock and the number of shares of our common stock as adjusted for full physical settlement of the forward sale agreements set forth in the line item captioned “Common stock” in the foregoing table are based on 89,270,661 shares of our common stock outstanding as of September 30, 2022, and such actual number of shares and the number of shares of our common stock as adjusted for the full physical settlement of the forward sale agreements set forth in such line item exclude:

(a) (i) 280,659 shares of our common stock reserved for issuance upon vesting of our time based restricted stock units (including reinvested dividends) outstanding as of September 30, 2022, (iii) 298,436 shares of our common stock reserved for issuance upon the vesting of our performance based restricted stock units (including reinvested dividends), assuming the maximum payout was achieved, outstanding as of September 30, 2022 under our Plan and (iv) shares reserved for issuance upon the vesting of any awards we may have issued under the Plan subsequent to September 30, 2022;

(b) any additional shares of common stock we may issue from and after October   , 2022 through final settlement of the forward sale agreements;

(c) any additional shares of common stock we may issue under our ESPP subsequent to September 30, 2022;

(d) any additional shares of common stock we may repurchase under our Share Repurchase Program subsequent to September 30, 2022; and

(e) any additional shares we have issued or may issue under our DRIP subsequent to September 30, 2022.

In addition, the number of shares of our common stock to be outstanding immediately after this offering, assuming full physical settlement of the forward sale agreements, as set forth above is based upon the assumed number of shares that we will be obligated to issue upon settlement of the forward sale agreements upon physical settlement of the forward sale agreements.

Under the ESPP, we are currently delivering newly issued shares of our common stock. Over the 12 months ended September 30, 2022, approximately 33,121 shares of our common stock were issued in connection with the ESPP.

Under the Stock Repurchase Program, we may repurchase up to 350,000 shares at a maximum sale price of $60. Over the 12 months ended September 30, 2022, approximately 350,000 shares of our common stock were repurchased in connection with the Stock Repurchase Plan.

Under the DRIP, we are currently delivering newly issued shares of our common stock to settle shares purchased. Over the 12 months ended September 30, 2022, approximately 1,168 shares of our common stock were issued in connection with the DRIP. The number of additional shares issued under the DRIP going forward is dependent on whether PGE continues to deliver newly issued shares under the DRIP, PGE’s stock price and the elections by plan participants to purchase PGE common stock in the future.

The number of shares of our common stock to be outstanding as adjusted for the full physical settlement of the forward sale agreements also assumes that no event will occur that would require us to sell shares of our common stock to the underwriters in lieu of the forward sellers selling shares of our common stock to the underwriters. If such an event occurs, (i) the number of shares of our common stock to be outstanding prior to any full physical settlement of the forward sale agreement would be increased by such number of shares and (ii) the number of shares of our common stock issuable pursuant to physical settlement of the forward sale agreements would be reduced by such number of shares.

The information contained in the table above assumes that the option granted to the underwriters in this offering to purchase additional shares of our common stock is not exercised.

Our common stock is listed on the NYSE under the symbol “POR.” The following table sets forth the high and low sale prices, as reported in the consolidated transaction reporting system. As of October 24, 2022, there were 89,272,904 shares of our common stock outstanding.

On October 24, 2022, the last reported sale price of our common stock on the NYSE was $43.75. As of October 24, 2022, there were approximately 1,078 holders of record of our common stock.

While we have paid regular quarterly cash dividends and expect to pay comparable quarterly dividends on the shares of our common stock in the future, the declaration of any dividends is at the discretion of our board of directors. The amount of any dividend declaration depends upon factors that the board of directors deems relevant and may include, but are not limited to, our results of operations and financial condition, future capital expenditures and investments, and applicable regulatory and contractual restrictions. See “Risk Factors – Risks Related to Our Common Stock – We may be unable to, or may choose not to, continue to pay dividends on our common stock at current or planned rates or at all.”

The following discussion is a summary of the material U.S. federal income tax considerations to Non-U.S. Holders (as defined below) of the purchase, ownership and disposition of our common stock sold pursuant to this offering, but does not purport to be a complete analysis of all potential tax effects. The effects of other U.S. federal tax laws, such as estate and gift tax laws, and any applicable state, local or non-U.S. tax laws are not discussed. This discussion is based on the U.S. Internal Revenue Code of 1986, as amended (the “Code”), Treasury Regulations promulgated thereunder, judicial decisions, and published rulings and administrative pronouncements of the U.S. Internal Revenue Service (the “IRS”), in each case in effect as of the date hereof. These authorities may change or be subject to differing interpretations. Any such change or differing interpretation may be applied retroactively in a manner that could adversely affect a Non-U.S. Holder of our common stock. We have not sought and will not seek any rulings from the IRS regarding the matters discussed below. There can be no assurance the IRS or a court will not take a contrary position to that discussed below regarding the tax consequences of the purchase, ownership and disposition of our common stock.

This discussion is limited to Non-U.S. Holders that hold our common stock as a “capital asset” within the meaning of Section 1221 of the Code (generally, property held for investment). This discussion does not address all U.S. federal income tax consequences that may be relevant to a Non-U.S. Holder’s particular circumstances, including the impact of the alternative minimum tax and of the Medicare contribution tax on net investment income. In addition, it does not address consequences relevant to Non-U.S. Holders subject to special rules, including, without limitation:

If an entity treated as a partnership for U.S. federal income tax purposes holds our common stock, the tax treatment of a partner in the partnership will depend on the status of the partner, the activities of the partnership and certain determinations made at the partner level. Accordingly, partnerships holding our common stock and the partners in such partnerships should consult their tax advisors regarding the U.S. federal income tax consequences to them.

THIS DISCUSSION IS FOR INFORMATIONAL PURPOSES ONLY AND IS NOT TAX ADVICE. INVESTORS SHOULD CONSULT THEIR TAX ADVISORS WITH RESPECT TO THE APPLICATION OF THE U.S. FEDERAL INCOME TAX LAWS TO THEIR PARTICULAR SITUATIONS AS WELL AS ANY TAX CONSEQUENCES OF THE PURCHASE, OWNERSHIP AND DISPOSITION OF OUR COMMON STOCK ARISING UNDER THE U.S. FEDERAL ESTATE OR GIFT TAX LAWS OR UNDER THE LAWS OF ANY STATE, LOCAL OR NON-U.S. TAXING JURISDICTION OR UNDER ANY APPLICABLE INCOME TAX TREATY.

For purposes of this discussion, a “Non-U.S. Holder” is any beneficial owner of our common stock that is neither a “U.S. person” nor an entity treated as a partnership for U.S. federal income tax purposes. A U.S. person is any person that, for U.S. federal income tax purposes, is or is treated as any of the following:

If we make distributions of cash or property on our common stock, such distributions will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Amounts not treated as dividends for U.S. federal income tax purposes will constitute a return of capital and first be applied against and reduce a Non-U.S. Holder’s adjusted tax basis in its common stock, but not below zero. Any excess will be treated as capital gain and will be treated as described below under “– Sale or Other Taxable Disposition.”

Subject to the discussion below on effectively connected income, dividends paid to a Non-U.S. Holder of our common stock will be subject to U.S. federal withholding tax at a rate of 30% of the gross amount of the dividends (or such lower rate specified by an applicable income tax treaty, provided the Non-U.S. Holder furnishes a valid IRS Form W-8BEN or W-8BEN-E (or other applicable documentation) certifying qualification for the lower treaty rate). If a Non-U.S. Holder holds the stock through a financial institution or other intermediary, the Non-U.S. Holder will be required to provide appropriate documentation to the intermediary, which then will be required to provide certification to the applicable withholding agent, either directly or through other intermediaries. A Non-U.S. Holder that does not timely furnish the required documentation, but that qualifies for a reduced treaty rate, may obtain a refund of any excess amounts withheld by timely filing an appropriate claim for refund with the IRS. Non-U.S. Holders should consult their tax advisors regarding their entitlement to benefits under any applicable income tax treaty.

If dividends paid to a Non-U.S. Holder are effectively connected with the Non-U.S. Holder’s conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, the Non-U.S. Holder maintains a permanent establishment in the United States to which such dividends are attributable), the Non-U.S. Holder will be exempt from the U.S. federal withholding tax described above. To claim the exemption, the Non-U.S. Holder must furnish to the applicable withholding agent a valid IRS Form W-8ECI, certifying that the dividends are effectively connected with the Non-U.S. Holder’s conduct of a trade or business within the United States.

Any such effectively connected dividends will be subject to U.S. federal income tax on a net-income basis at the regular rates. A Non-U.S. Holder that is a corporation also may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on such effectively connected dividends, as adjusted for certain items. Non-U.S. Holders should consult their tax advisors regarding any applicable tax treaties that may provide for different rules.

A Non-U.S. Holder will not be subject to U.S. federal income tax on any gain realized upon the sale or other taxable disposition of our common stock unless:

Gain described in the first bullet point above generally will be subject to U.S. federal income tax on a net-income basis at the regular rates. A Non-U.S. Holder that is a corporation also may be subject to a branch profits tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on such effectively connected gain, as adjusted for certain items.

A Non-U.S. Holder described in the second bullet point above will be subject to U.S. federal income tax at a rate of 30% (or such lower rate specified by an applicable income tax treaty) on gain realized upon the sale or other taxable disposition of our common stock, which may be offset by U.S. source capital losses of the Non-U.S. Holder (even though the individual is not considered a resident of the United States), provided the Non-U.S. Holder has timely filed U.S. federal income tax returns with respect to such losses.

With respect to the third bullet point above, we believe we currently are not, and do not anticipate becoming, a USRPHC. Because the determination of whether we are a USRPHC depends, however, on the fair market value of our USRPIs relative to the fair market value of our non-U.S. real property interests and our other business assets, there can be no assurance we currently are not a USRPHC or will not become one in the future. Even if we are or were to become a USRPHC, gain arising from the sale or other taxable disposition by a Non-U.S. Holder of our common stock will not be subject to U.S. federal income tax if our common stock is “regularly traded,” as defined by applicable Treasury Regulations, on an established securities market, and such Non-U.S. Holder owned, actually and constructively, 5% or less of our common stock throughout the shorter of the five-year period ending on the date of the sale or other taxable disposition and the Non-U.S. Holder’s holding period.

Non-U.S. Holders should consult their tax advisors regarding potentially applicable income tax treaties that may provide for different rules.

Payments of dividends on our common stock will not be subject to backup withholding, provided the applicable withholding agent does not have actual knowledge or reason to know the Non-U.S. holder is a U.S. person and the Non-U.S. holder either certifies its non-U.S. status, such as by furnishing a valid IRS Form W-8BEN, W-8BEN-E or W-8ECI, or otherwise establishes an exemption. However, information returns are required to be filed with the IRS in connection with any distributions on our common stock paid to the Non-U.S. Holder, regardless of whether such distributions constitute dividends or whether any tax was actually withheld. In addition, proceeds of the sale or other taxable disposition of our common stock within the United States or conducted through certain U.S.-related brokers generally will not be subject to backup withholding or information reporting if the applicable withholding agent receives the certification described above and does not have actual knowledge or reason to know that Non-U.S. holder is a U.S. person, or the Non-U.S. holder otherwise establishes an exemption. Proceeds of a disposition of our common stock conducted through a non-U.S. office of a non-U.S. broker generally will not be subject to backup withholding or information reporting.

Copies of information returns that are filed with the IRS may also be made available under the provisions of an applicable treaty or agreement to the tax authorities of the country in which the Non-U.S. Holder resides or is established.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against a Non-U.S. Holder’s U.S. federal income tax liability, provided the required information is timely furnished to the IRS.

Withholding taxes may be imposed under Sections 1471 to 1474 of the Code (such Sections commonly referred to as the Foreign Account Tax Compliance Act, or “FATCA”) on certain types of payments made to non-U.S. financial institutions and certain other non-U.S. entities. Specifically, a 30% withholding tax may be imposed on dividends on, or (subject to the proposed Treasury Regulations discussed below) gross proceeds from the sale or other disposition of, our common stock paid to a “foreign financial institution” or a “non-financial foreign entity” (each as defined in the Code), unless (1) the foreign financial institution undertakes certain diligence and reporting obligations, (2) the non-financial foreign entity either certifies it does not have any “substantial United States owners” (as defined in the Code) or furnishes identifying information regarding each substantial United States owner, or (3) the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from these rules. If the payee is a foreign financial institution and is subject to the diligence and reporting requirements in (1) above, it must enter into an agreement with the U.S. Department of the Treasury requiring, among other things, that it undertake to identify accounts held by certain “specified United States persons” or “United States-owned foreign entities” (each as defined in the Code), annually report certain information about such accounts, and withhold 30% on certain payments to non-compliant foreign financial institutions and certain other account holders. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to different rules.

Under the applicable Treasury Regulations and administrative guidance, withholding under FATCA generally applies to payments of dividends on our common stock. While withholding under FATCA would have applied also to payments of gross proceeds from the sale or other disposition of stock on or after January 1, 2019, proposed Treasury Regulations eliminate FATCA withholding on payments of gross proceeds entirely. Taxpayers generally may rely on these proposed Treasury Regulations until final Treasury Regulations are issued.

Prospective investors should consult their tax advisors regarding the potential application of withholding under FATCA to their investment in our common stock.

Barclays Capital Inc. and J.P. Morgan Securities LLC are acting as the representatives of the underwriters. Under the terms and subject to the conditions of an underwriting agreement dated the date of this prospectus supplement, each of the underwriters have agreed, severally and not jointly, to purchase, and the forward purchasers (or one of their respective affiliates) have agreed to sell to the underwriters, the number of shares of common stock shown opposite its name below:

The underwriters are offering the shares of common shares subject to their acceptance of the shares from the forward purchasers (or one of their respective affiliates) and subject to prior sale. The underwriting agreement provides that the obligations of the underwriters to pay for and accept delivery of the common shares offered by this prospectus supplement are subject to the approval of certain legal matters by their counsel and to certain other conditions. The underwriters are obligated to take and pay for all of the common shares offered by this prospectus supplement if any such shares are taken.

Our common stock is listed on the New York Stock Exchange under the symbol “POR.”

The underwriters propose to offer our common shares from time to time for sale in one or more transactions on the New York Stock Exchange, in the over-the-counter market, through negotiated transactions or otherwise at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices, subject to receipt and acceptance by them and subject to their right to reject any order in whole or in part. In connection with the sale of our common shares offered hereby, the underwriters may be deemed to have received compensation in the form of underwriting discounts. The underwriters may effect such transactions by selling our common shares to or through dealers, and such dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or purchasers of our common shares for whom they may act as agents or to whom they may sell as principal. The difference between the price at which the underwriters purchase common shares and the price at which the underwriters resell such common shares may be deemed underwriting compensation.

The expenses of the offering that are payable by us are estimated to be approximately $500,000 (excluding underwriting discounts and commissions). We have agreed to reimburse the underwriters for certain FINRA-related expenses incurred by them in connection with the offering in an amount up to $15,000 as set forth in the underwriting agreement. The underwriters have also agreed to reimburse us for certain of our expenses incurred with respect to this offering.

We expect to enter into separate forward sale agreements with each of the forward purchasers, relating to an aggregate of    shares of our common stock. In connection with the forward sale agreements, the forward purchasers (or affiliates thereof) are expected to borrow from third parties and sell to the underwriters an aggregate of    shares of our common stock that will be delivered in this offering.

If any forward purchaser or its affiliate does not deliver and sell all of the shares of our common stock to be delivered and sold by it pursuant to the terms of the underwriting agreement (including because insufficient shares of our common stock were made available by securities lenders for borrowing at a stock borrow cost below a specified threshold), we will issue and sell directly to the underwriters the number of shares of our common stock not delivered and sold by such forward purchaser or its affiliate, and under such circumstances the number of shares of our common stock underlying the relevant forward sale agreement will be decreased by the number of shares of our common stock that we issue and sell to the underwriters. Under any such circumstance, the commitment of the underwriters to purchase shares of our common stock from the relevant forward purchaser or its affiliate will be replaced with the

commitment to purchase from us, at a price equal to the public offering price less the underwriting discount per share, as set forth on the cover page of this prospectus supplement.

We will not receive any proceeds from the sale of our common stock by the forward purchasers or their affiliates, but we expect to receive an amount equal to the net proceeds from the sale of the borrowed shares of our common stock sold in this offering, subject to certain adjustments pursuant to the forward sale agreements, from the forward purchaser upon full physical settlement of the forward sale agreements. We will only receive such proceeds if we elect to fully physically settle the forward sale agreements.

The forward sale agreements provide for settlement on a settlement date or dates to be specified at our discretion, but which we expect to occur in one or more settlements on or prior to October 25, 2024. On a settlement date, if we decide to physically settle any forward sale agreement, we will issue shares of our common stock to the forward purchaser under the relevant forward sale agreement at the forward sale price. The forward sale price initially will be equal to the public offering price less the underwriting discount per share, as set forth on the cover page of this prospectus supplement. The forward sale price that we expect to receive upon physical settlement of each forward sale agreement will be subject to adjustment on a daily basis based on a floating interest rate factor equal to a specified daily rate less a spread and will be decreased based on amounts related to expected dividends on our common stock during the term of the applicable forward sale agreement. If the specified daily rate is less than the spread on any day, the interest rate factor will result in a daily reduction of the forward sale price.

Before settlement of any forward sale agreement, we expect that the shares issuable upon settlement of such forward sale agreement will be reflected in our diluted earnings per share, return on equity and dividends per share calculations using the treasury stock method. Under this method, the number of shares of our common stock used in calculating diluted earnings per share, return on equity and dividends per share is deemed to be increased by the excess, if any, of the number of shares of our common stock that would be issued upon full physical settlement of such forward sale agreement over the number of shares of our common stock that could be purchased by us in the market (based on the average market price during the period) using the proceeds receivable upon full physical settlement (based on the average adjusted forward sale price during the reporting period). Consequently, we anticipate there will be no dilutive effect on our earnings per share, return on equity and dividends per share prior to physical or net share settlement of the forward sale agreements and subject to the occurrence of certain events, except during periods when the average market price of our common stock is above the average forward sale price, which is initially $    per share (equal to the public offering price less the underwriting discount per share, as set forth on the cover page of this prospectus supplement).

We may elect, subject to certain conditions, cash settlement or net share settlement for all or a portion of our obligations under the forward sale agreements. If we elect to cash or net share settle all or a portion of the shares of our common stock underlying any forward sale agreements, we would expect the applicable forward purchasers or their respective affiliates to purchase the number of shares necessary, based on the number of shares with respect to which we have elected cash or net share settlement, in order to satisfy their obligation to return shares of our common stock to securities lenders to unwind such forward purchaser’s hedge (after taking into consideration any shares of our common stock to be delivered by us to such forward purchaser, in the case of net share settlement); and, if applicable in connection with net share settlement, to deliver shares of our common stock to us or taking into account shares of our common stock to be delivered by us, as applicable. If the Rule 10b-18 volume weighted average price over the relevant unwind period (in the case of cash settlement) or the price paid by the applicable forward purchasers or their respective affiliates to so purchase our common stock (in the case of net share settlement), in each case, is above the applicable forward sale price at that time, we will pay or deliver, as the case may be, to the applicable forward purchasers under the applicable forward sale agreements, an amount in cash, or a number of shares of our common stock with a market value, equal to such difference. Any such difference could be significant. Conversely, if the Rule 10b-18 volume weighted average price over the relevant unwind period (in the case of cash settlement) or the price paid by the applicable forward purchasers or their respective affiliates to so purchase our common stock (in the case of net share settlement), in each case, is below the applicable forward sale price at that time, the applicable forward purchasers will pay or deliver, as the case may be, to us under the applicable forward sale agreements, an amount in cash, or a number of shares of our common stock with a market value, equal to such difference.

In addition, the purchase of our common stock by forward purchasers or their respective affiliates, to unwind the forward purchasers’ hedge position, could cause the price of our common stock to increase over time,

thereby increasing the amount of cash or the number of shares of our common stock that we would owe to the applicable forward purchasers upon cash settlement or net share settlement, as the case may be, of the applicable forward sale agreements, or decreasing the amount of cash or the number of shares of our common stock that the applicable forward purchasers owe us upon cash settlement or net share settlement, as the case may be, of the applicable forward sale agreements.

Each forward purchaser will have the right to accelerate its respective forward sale agreement (or, in certain cases, the portion thereof that it determines is affected by the relevant event) and require us to physically settle the applicable forward sale agreement on a date specified by the applicable forward purchasers if (1) in its commercially reasonable judgment, it or its affiliate is unable to hedge (or maintain a hedge of) its exposure in a commercially reasonable manner under such forward sale agreement because insufficient shares of our common stock have been made available for borrowing by securities lenders, or (b) it or its affiliates would incur a stock borrow cost in excess of a specified threshold; (2) we declare any dividend, issue or distribution on shares of our common stock that is payable in (a) cash in excess of specified amounts (unless it constitutes an extraordinary dividend under the forward sale agreement), (b) securities of another company that we acquire or own (directly or indirectly) as a result of a spin-off or similar transaction, or (c) any other type of securities (other than our common stock), rights, warrants or other assets for payment at less than the prevailing market price; (3) certain ownership thresholds applicable to such forward purchaser and its affiliates are or would be exceeded; (4) an event (a) is announced that if consummated would result in certain mergers or tender offers, as well as certain events involving our nationalization, our insolvency or a delisting of our common stock or (b) occurs that would constitute a hedging disruption or a change in law; or (5) certain other events of default or termination events occur, including, among others, any material misrepresentation made by us in connection with such forward sale agreement (each as more fully described in the relevant forward sale agreement).

A forward purchaser’s decision to exercise its right to accelerate its respective forward sale agreement (or, in certain cases , the portion thereof that it determines as is affected by the relevant event) and to require us to settle such forward sale agreement will be made irrespective of our interests, including our need for capital. In such cases, we could be required to issue and deliver our common stock under the terms of the physical settlement provisions of the relevant forward sale agreement irrespective of our capital needs, which would result in dilution to our earnings per share and may adversely affect the market price of our common stock. In addition, upon certain events of bankruptcy, insolvency or reorganization relating to us, the forward sale agreement will terminate without further liability of either party. Following any such termination, we would not issue any shares of our common stock and we would not receive any proceeds pursuant to the forward sale agreement. See “Risk Factors—Risks Related to the Forward Sale Agreements.

The underwriters have been granted the option, exercisable in whole or from time to time in part to purchase up to an additional $56,250,000 of shares of our common stock at the public offering price per shares shown above, less the underwriting discount, exercisable for 30 days after the date of this prospectus supplement

Upon any exercise of such option, we expect to enter into additional forward sale agreements with each of the forward purchasers in respect of the number of shares sold to the underwriters by the applicable forward purchaser or its affiliate in connection with the exercise of such option. In such event, if the forward purchasers determine in good faith, after using commercially reasonable efforts, that the forward sellers are unable to borrow and deliver for sale to the underwriters on the anticipated closing date for the exercise of such option the number of shares of our common stock in respect of which such option has been exercised or that the forward sellers are unable to borrow, at a stock loan rate not greater than a specified rate, and deliver for sale to the underwriters on the anticipated closing date for each exercise of such option the number of shares of our common stock in respect of which such option has been exercised, or if the forward sellers elect, in connection with the exercise of such option, not to borrow shares of our common stock and sell such shares to the underwriters, because certain conditions in the underwriting agreement for this offering are not satisfied, we will issue and sell directly to the underwriters the number of shares of our common stock not delivered and sold by such forward purchaser or its affiliate to the underwriters, and under such circumstances the number of shares of our common stock underlying the relevant additional forward sale agreement will be decreased by the number of shares of our common stock that we issue and sell to the underwriters. Upon any exercise of such option, if we do not enter into additional forward sale agreements with the forward purchasers, we will issue and sell to the underwriters the number of shares of our common stock in respect of which such option has been exercised.

PGE and its directors and executive officers have entered into lock-up agreements with the underwriters prior to the commencement of this offering pursuant to which we and each of these persons, with limited exceptions including those described below, for a period of 60 days after the date of this prospectus supplement, may not, without the prior written consent of Barclays Capital Inc. and J.P. Morgan Securities LLC, (1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend or otherwise transfer or dispose of, directly or indirectly, any shares of common stock or any securities convertible into or exercisable or exchangeable for common stock (including without limitation, common stock or such other securities which may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and securities which may be issued pursuant to any stock incentive plan, employee stock purchase plan or dividend reinvestment plan of PGE, upon the settlement of dividend equivalent rights or upon exercise of a stock option or warrant), or publicly disclose the intention to undertake any of the forgoing, (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the common stock or such other securities, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of common stock or such other securities, in cash or otherwise or (3) make any demand for or exercise any right with respect to, the registration of any shares of common stock or any security convertible into or exercisable or exchangeable for common stock.

The restrictions described in the immediately preceding paragraph and contained in the lock-up agreements between the Representatives and the lock-up parties do not apply, subject in certain cases to various conditions, to certain transactions, including: (a) the acquisition of common stock pursuant to any stock incentive plan or employee stock purchase plan in effect at, or any dividend reinvestment plan approved by the Company’s board of directors prior to, the time of this prospectus; (b) the acquisition of common stock upon the settlement of dividend equivalent rights outstanding at the time of this prospectus; (c) forfeiture, cancellation, withholding, surrender or delivery of shares of common stock to the company pursuant to a broker arrangement to satisfy any income, employment and/or social security tax withholding and/or remittance obligations in connection with the vesting during the lock-up period of any restricted stock unit, restricted shares, performance share unit or phantom shares; provided that no filing under Section 16(a) of the Exchange Act or other public announcement shall be required or shall be made voluntarily in connection with such forfeiture, cancellation, withholding, surrender or delivery, other than a filing on Form 4; (d) transfers of shares of common stock to accounts that the lock-up party controls that result only in a change in the form of the lock-up party’s beneficial ownership of securities without changing the undersigned’s pecuniary interest in the securities and that do not result in the obligation to file a report pursuant to Section 16 of the Exchange Act; (e) transfers of shares of common stock as a bona fide gift, provided that (i) each donee shall sign and deliver a lock-up letter (provided that (x) if the undersigned transfers shares of common stock which, in the aggregate, represent no more than 5,000 common share equivalents to donees who are bona fide charities, no such bona fide charities shall be required to deliver such lock-up letters to the Representatives, but (y) if the undersigned transfers shares of Common Stock and Convertible Securities which, in the aggregate, represent more than 5,000 common share equivalents to donees who are bona fide charities, then all such charities must deliver such lock-up letters to the Representatives), and (ii) no filing under Section 16(a) of the Exchange Act, or other public announcement, reporting a reduction in beneficial ownership of shares of common stock, shall be required or shall be voluntarily made during the lock-up period, except that a Form 4 filing permitted by clause (c) above may also reflect a reduction in beneficial ownership resulting from a bona fide gift made in accordance with this clause (e) so long as such Form 4 expressly states that such reduction is the result of a bona fide gift; (f) transfers of shares of common stock either during the lock-up party’s lifetime or on death (i) by will or intestacy, (ii) to a trust the beneficiaries of which are exclusively the lock-up party and/or a member or members of his or her immediate family, or (iii) by operation of law, including domestic relations order, provided that each such transferee shall sign and deliver a lock-up letter; (g) transfers of shares of common stock pursuant to a bona fide third-party tender offer, merger, consolidation or other similar transaction approved by the Company’s board of directors and made to all holders of the Company’s securities involving a “change of control” of the Company, provided that in the event that such tender offer, merger, consolidation or other such transaction is not completed, such shares of common stock held by the undersigned shall remain subject to the provisions of the lock-up letter; or (h) the establishment of a trading plan pursuant to Rule 10b5-1 under the Exchange Act, provided that such plan does not provide for the transfer of common stock during the lock-up period and no public announcement or filing under the Exchange Act or otherwise regarding the establishment of such plan shall be required or shall be voluntarily made by or on behalf of the lock-up party or the Company.

Barclays Capital Inc. and J.P. Morgan Securities LLC in their discretion, may release the common stock and other securities subject to the lock-up agreements described above in whole or in part at any time with or without notice. When determining whether or not to release common stock and other securities from lock-up agreements, Barclays Capital Inc. and J.P. Morgan Securities LLC will consider, among other factors, the holder’s reasons for requesting the release, the number of shares of common stock and other securities for which the release is being requested and market conditions at the time.

We have agreed to indemnify the underwriters and the forward purchasers against certain liabilities, including liabilities under the Securities Act of 1933, as amended, and to contribute to payments that the underwriters may be required to make for these liabilities.

The representatives may engage in stabilizing transactions, short sales and purchases to cover positions created by short sales, and penalty bids or purchases for the purpose of pegging, fixing or maintaining the price of the common stock, in accordance with Regulation M under the Exchange Act:

These stabilizing transactions, syndicate covering transactions and penalty bids may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of the common stock. As a result, the price of the common stock may be higher than the price that might otherwise exist in the open market. These transactions may be effected on the New York Stock Exchange or otherwise and, if commenced, may be discontinued at any time.

Neither we nor any of the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of the common stock. In addition, neither we nor any of the underwriters make representation that the representatives will engage in these stabilizing transactions or that any transaction, once commenced, will not be discontinued without notice.

In connection with the offering, certain of the underwriters or securities dealers may distribute prospectuses by electronic means, such as e-mail.

Certain of the underwriters and their related entities have engaged and may engage in commercial and investment banking transactions with us in the ordinary course of their business. They have received customary compensation and expenses for these commercial and investment banking transactions. The underwriters and their respective affiliates may in the future provide various investment banking and other services to us, and our affiliates, for which they would receive customary compensation from us.

In addition, in the ordinary course of their business activities, the underwriters and their affiliates may make or hold a broad array of investments and actively traded debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers. Such investments and securities activities may involve securities and/or instruments of ours or our affiliates. The underwriters or their affiliates that have a lending relationship with us may hedge their credit exposure to us consistent with their customary risk management policies. Typically, investment banking and other financial institutions, like the underwriters and their affiliates, would hedge such exposure by entering into transactions that consist of either the purchase of credit default swaps or the creation of short positions in our securities, including potentially the shares offered hereby. Any such credit default swaps or short positions could adversely affect future trading prices of the shares offered hereby. The underwriters and their affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

In addition, an affiliate of Barclays Capital Inc., an underwriter in this offering, is a lender under our Term Loan that will be repaid with a portion of the net proceeds that we will receive upon settlement of the forward sale agreements we plan to enter into in connection with this offering. As a result, we expect affiliates of Barclays Capital Inc. to receive a portion of the net proceeds of this offering.

All of the proceeds from the sale of shares of our common stock offered in this offering (excluding proceeds, if any, paid to us with respect to any shares of common stock that we may sell to the underwriters in lieu of the forward sellers selling such shares and excluding proceeds we may receive if the underwriters exercise their option to purchase additional shares of common stock directly from us) will be paid to the forward purchasers. In addition, an affiliate of Barclays Capital Inc., an underwriter in this offering, is a lender under our Term Loan that will be repaid with a portion of the net proceeds that we will receive upon settlement of the forward sale agreements we plan to enter into in connection with this offering. Because Barclays Capital Inc. and J.P. Morgan Securities LLC, or their affiliates, will receive more than 5% of the net proceeds of this offering, Barclays Capital Inc. and J.P. Morgan Securities LLC are deemed to have a conflict of interest within the meaning of Rule 5121 (Public Offerings of Securities with Conflicts of Interest) of FINRA Rule 5121. Accordingly, this offering is being conducted in compliance with the applicable provisions of FINRA Rule 5121. Pursuant to that rule, the appointment of a “qualified independent underwriter” is not required in connection with this offering, as the shares of our common stock have a “bona fide public market” (as defined in FINRA Rule 5121). In addition, Barclays Capital Inc. and J.P. Morgan Securities LLC may not make sales in this offering to any discretionary account without the prior written approval of the customer.

In relation to each Member State of the European Economic Area and the United Kingdom (each, a “Relevant State”), no shares have been offered or will be offered pursuant to the offering to the public in that Relevant State prior to the publication of a prospectus supplement in relation to the shares which has been approved by the competent authority in that Relevant State or, where appropriate, approved in another Relevant State and notified to the competent authority in that Relevant State, all in accordance with the Prospectus Regulation), except that offers of shares may be made to the public in that Relevant State other than at any time under the following exemptions under the Prospectus Regulation:

A. to any legal entity which is a qualified investor as defined under the Prospectus Regulation;

B. to fewer than 150, natural or legal persons (other than qualified investors as defined under the Prospectus Regulation), subject to obtaining the prior consent of the underwriters; or

C. in any other circumstances falling within Article 1(4) of the Prospectus Regulation, provided that no such offer of shares shall require us or any underwriter to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the Prospectus Regulation and each person who initially acquires any shares or to whom any offer is made will be deemed to have represented, acknowledged and agreed to and with each of the underwriters and us that it is a “qualified investor” implementing Article 2(e) of the Prospectus Regulation.

In the case of any shares being offered to a financial intermediary as that term is used in the Prospectus Regulation, each such financial intermediary will be deemed to have represented, acknowledged and agreed that the shares acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer of any shares to the public other than their offer or resale in a Relevant State to qualified investors as so defined or in circumstances in which the prior consent of the underwriters have been obtained to each such proposed offer or resale. For the purposes of this provision, the expression an “offer to the public” in relation to any shares in any Relevant State means the communication in any form and by any means of sufficient information on the terms of the offer and any shares to be offered so as to enable an investor to decide to purchase or subscribe for any shares of our common stock, and the expression “Prospectus Regulation” means Regulation (EU) 2017/1129. References to the Prospectus Regulation includes, in relation to the United Kingdom, the Prospectus Regulation as it forms part of United Kingdom domestic law by virtue of the European Union (Withdrawal) Act 2018.

In addition, in the United Kingdom, this document is being distributed only to, and is directed only at, and any offer subsequently made may only be directed at persons who are “qualified investors” (as defined in the Prospectus Regulation) (i) who have professional experience in matters relating to investments falling within Article 19 (5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended, or the Order, and/or (ii) who are high net worth companies (or persons to whom it may otherwise be lawfully communicated) falling within Article 49(2)(a) to (d) of the Order (all such persons together being referred to as “relevant persons”) or otherwise in circumstances which have not resulted and will not result in an offer to the public of the shares of our common stock in the United Kingdom within the meaning of the Financial Services and Markets Act 2000.

Any person in the United Kingdom that is not a relevant person should not act or rely on the information included in this document or use it as basis for taking any action. In the United Kingdom, any investment or investment activity that this document relates to may be made or taken exclusively by relevant persons.

The shares may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the shares must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement or the accompanying prospectus (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

The shares may not be publicly offered in Switzerland and will not be listed on the SIX Swiss Exchange (“SIX”) or on any other stock exchange or regulated trading facility in Switzerland. This document does not constitute a prospectus within the meaning of, and has been prepared without regard to the disclosure standards for issuance

prospectuses under art. 652a or art. 1156 of the Swiss Code of Obligations or the disclosure standards for listing prospectuses under art. 27 ff. of the SIX Listing Rules or the listing rules of any other stock exchange or regulated trading facility in Switzerland. Neither this document nor any other offering or marketing material relating to the shares or the offering may be publicly distributed or otherwise made publicly available in Switzerland.

Neither this document nor any other offering or marketing material relating to the offering, the Company, the shares have been or will be filed with or approved by any Swiss regulatory authority. In particular, this document will not be filed with, and the offer of shares will not be supervised by, the Swiss Financial Market Supervisory Authority FINMA, and the offer of shares has not been and will not be authorized under the Swiss Federal Act on Collective Investment Schemes (“CISA”). The investor protection afforded to acquirers of interests in collective investment schemes under the CISA does not extend to acquirers of shares.

This prospectus supplement relates to an Exempt Offer in accordance with the Offered Securities Rules of the Dubai Financial Services Authority (“DFSA”). This prospectus supplement is intended for distribution only to persons of a type specified in the Offered Securities Rules of the DFSA. It must not be delivered to, or relied on by, any other person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement nor taken steps to verify the information set forth herein and has no responsibility for the prospectus supplement. The shares to which this prospectus supplement relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the shares offered should conduct their own due diligence on the shares. If you do not understand the contents of this prospectus supplement you should consult an authorized financial advisor.

In relation to its use in the DIFC, this document is strictly private and confidential and is being distributed to a limited number of investors and must not be provided to any person other than the original recipient, and may not be reproduced or used for any other purpose. The interests in the securities may not be offered or sold directly or indirectly to the public in the DIFC.

This prospectus:

The shares may not be directly or indirectly offered for subscription or purchased or sold, and no invitations to subscribe for or buy the shares may be issued, and no draft or definitive offering memorandum, advertisement or other offering material relating to any shares may be distributed in Australia, except where disclosure to investors is not required under Chapter 6D of the Corporations Act or is otherwise in compliance with all applicable Australian laws and regulations. By submitting an application for the shares, you represent and warrant to us that you are an Exempt Investor.

As any offer of shares under this document will be made without disclosure in Australia under Chapter 6D.2 of the Corporations Act, the offer of those securities for resale in Australia within 12 months may, under section 707 of the Corporations Act, require disclosure to investors under Chapter 6D.2 if none of the exemptions in section 708 applies to that resale. By applying for the shares you undertake to us that you will not, for a period of 12 months from the date of issue of the shares, offer, transfer, assign or otherwise alienate those securities to investors in Australia except in circumstances where disclosure to investors is not required under Chapter 6D.2 of the Corporations Act or where a compliant disclosure document is prepared and lodged with ASIC.

Certain legal matters relating to this offering will be passed upon for us by Latham & Watkins LLP, and certain legal matters will be passed upon for us by Angelica Espinosa, our General Counsel. As of October 24, 2022, Ms. Espinosa owned no shares of our common stock. Pursuant to various stock and employee benefit plans, Ms. Espinosa is eligible to purchase and receive shares of our common stock and to receive options to purchase shares of common stock. Davis Polk & Wardwell LLP, will act as counsel to the underwriters and the forward purchasers.

The financial statements of Portland General Electric Company as of December 31, 2021 and 2020, and for each of the three years in the period ended December 31, 2021, incorporated by reference in this Prospectus Supplement, and the effectiveness of Portland General Electric Company’s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

We file annual, quarterly and special reports, proxy statements and other information with the SEC. The SEC also maintains a web site that contains reports, proxy and information statements, and other information regarding registrants that file electronically with the SEC at www.sec.gov. You can inspect reports and other information we file at the offices of the New York Stock Exchange, 20 Broad Street, New York, New York 10005. In addition, we maintain a web site that contains information about us at www.portlandgeneral.com. The information found on, or otherwise accessible through, our website is not incorporated into, and does not form a part of, this prospectus supplement, the accompanying prospectus or any other report or document we file with or furnish to the SEC.

We have filed with the SEC a registration statement on Form S-3 (File No. 333-266454), of which this prospectus supplement and the accompanying prospectus are a part, including exhibits, schedules and amendments filed with, or incorporated by reference in, such registration statement, under the Securities Act. This prospectus supplement and the accompanying prospectus do not contain all of the information set forth in the registration statement and exhibits and schedules to the registration statement. For further information with respect to our company, reference is made to the registration statement, including the exhibits to the registration statement. Statements contained in this prospectus supplement and the accompanying prospectus as to the contents of any contract or other document referred to, or incorporated by reference, in this prospectus supplement and the accompanying prospectus are not necessarily complete and, where that contract or document is an exhibit to the registration statement, each statement is qualified in all respects by the exhibit to which the reference relates. The registration statement is available to you on the SEC’s web site, www.sec.gov.

The SEC allows us to “incorporate by reference” the information we file with the SEC. This means that we can disclose important information to you by referring you to another filed document. Any information referred to in this way is considered part of this prospectus supplement from the date we file that document. Any reports filed by us with the SEC after the date of this prospectus supplement and before the date that the offering of the securities by means of this prospectus supplement is terminated will automatically update and, where applicable, supersede any information contained in this prospectus supplement or incorporated by reference in this prospectus supplement. Accordingly, we incorporate by reference the following documents or information filed with the SEC:

We also incorporate by reference all documents we may subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act after the initial filing date of the registration statement of which this prospectus is a part and prior to the termination of the offering (other than documents or information deemed to have been furnished and not filed in accordance with SEC rules). The most recent information that we file with the SEC automatically updates and supersedes older information. The information contained in any such filing will be deemed to be a part of this prospectus, commencing on the date on which the document is filed.

We will provide to each person, including any beneficial owner, to whom a copy of this prospectus has been delivered, without charge, upon the written or oral request of such person, a copy of any or all of the documents which are incorporated by reference into this prospectus, other than exhibits to such documents, unless such exhibits are specifically incorporated by reference into the information that this prospectus incorporates. You should direct requests for such copies to: