Eversource Energy (ES) 424B3Prospectus supplement

We make statements in this prospectus supplement and the accompanying prospectus and in the documents we incorporate by reference that are statements concerning our expectations, beliefs, plans, objectives, goals, strategies, assumptions of future events, future financial performance or growth and other statements that are not historical facts. These statements are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. You can generally identify our forward- looking statements through the use of words or phrases such as “estimate,” “expect,” “anticipate,” “intend,” “plan,” “project,” “believe,” “forecast,” “should,” “could,” and other similar expressions. Forward-looking statements are based on the current expectations, estimates, assumptions or projections of management and are not guarantees of future performance. These expectations, estimates, assumptions or projections may vary materially from actual results. Accordingly, any such statements are qualified in their entirety by reference to, and are accompanied by, the following important factors that could cause our actual results to differ materially from those contained in our forward-looking statements, including, but not limited to:

Other risk factors are detailed in reports we file with the Commission, and we encourage you to consult such disclosures.

All such factors are difficult to predict and contain uncertainties that may materially affect our actual results, many of which are beyond our control. You should not place undue reliance on the forward-looking statements, each of which speaks only as of the date on which such statement is made, and, except as

The Notes are a separate series of the Senior Notes described in the accompanying prospectus and will be issued under the Twentieth Supplemental Indenture, to be dated as of November 1, 2023, between us and The Bank of New York Mellon Trust Company, N.A., formerly known as The Bank of New York Trust Company, N.A. (as successor trustee to The Bank of New York), as trustee (the “Trustee”), supplementing our Indenture with the Trustee, dated as of April 1, 2002 (the “Senior Note Indenture”), described in the accompanying prospectus. You should read the accompanying prospectus for a detailed summary of additional provisions of the Senior Notes, which includes the Notes, and of the Senior Note Indenture. The description of the Notes below supplements the description of the Senior Notes contained in the accompanying prospectus. If the descriptions are inconsistent, this prospectus supplement controls. The following summary and the description set forth in the accompanying prospectus do not purport to be complete and are subject to, and qualified in their entirety by, all provisions of the Senior Note Indenture. Capitalized terms used but not defined in this prospectus supplement have the meanings given to them in the accompanying prospectus.

The Notes will constitute the twenty-ninth series of our Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series A, Due 2012, in the aggregate principal amount of $263,000,000, which were issued on April 4, 2002 and repaid on April 2, 2012, constituted the first series of Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series B, Due 2008, in the aggregate principal amount of $150,000,000, which were issued on June 3, 2003 and repaid on June 2, 2008, constituted the second series of Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series C, Due 2013, in the aggregate principal amount of $250,000,000, which were issued on June 5, 2008 and repaid on June 3, 2013, constituted the third series of Senior Notes issued under our Senior Note Indenture. Our Floating Rate Notes, Series D, Due 2013, in the aggregate principal amount of $300,000,000, which were issued on March 22, 2012 and repaid on September 20, 2013, constituted the fourth series of Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series E, Due 2018, in the aggregate principal amount of $300,000,000, which were issued on May 13, 2013, and repaid on May 1, 2018, constituted the fifth series of Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series F, Due 2023, in the aggregate principal amount of $450,000,000, which were issued on May 13, 2013 and repaid on May 1, 2023, constituted the sixth series of Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series G, Due 2018, in the aggregate principal amount of $150,000,000, which were issued on January 15, 2015, and repaid on January 15, 2018, constituted the seventh series of Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series H, Due 2025, in the aggregate principal amount of $300,000,000, which were issued on January 15, 2015, constituted the eighth series of Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series I, Due 2021, in the aggregate principal amount of $450,000,000, which were issued on March 10, 2016 and January 8, 2018, and repaid on February 16, 2021, constituted the ninth series of our Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series J, Due 2026, in the aggregate principal amount of $250,000,000, which were issued on March 10, 2016, constituted the tenth series of our Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series K, Due 2022, in the aggregate principal amount of $750,000,000, which were issued on March 10, 2017 and October 5, 2017, and repaid on March 15, 2022, constituted the eleventh series of our Senior Notes issued under the Senior Note Indenture. Our Senior Notes, Series L, Due 2024, in the aggregate principal amount of $450,000,000, which were issued on October 5, 2017, constituted the twelfth series of our Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series M, Due 2028, in the aggregate principal amount of $450,000,000, which were issued on January 8, 2018, constituted the thirteenth series of our Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series N, Due 2023, in the aggregate principal amount of $400,000,000, which were issued on December 13, 2018, constituted the fourteenth series of our Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series O, Due 2029, in the aggregate principal amount of $500,000,000, which were issued on December 13, 2018, constituted the fifteenth series of our Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series P, Due 2050, in the aggregate principal amount of $650,000,000, which were issued on January 10, 2020 and August 14, 2020, constituted the sixteenth series of our Senior Notes issued under our Senior Note Indenture. Our Senior Notes, Series Q, Due 2025, in the aggregate principal amount of $300,000,000, which were issued on August 14, 2020, constituted the seventeenth series of our Senior Notes issued

The Notes are initially being offered in the aggregate principal amount of $          and will mature on February 1, 2029. The Notes are not entitled to the benefit of any sinking fund. The Senior Note Indenture permits the defeasance of the Senior Notes upon satisfaction of the conditions described under “Description of Securities Registered — Eversource Energy — Senior Notes — Defeasance” in the accompanying prospectus and “— Defeasance” below.

The Notes will constitute unsecured and unsubordinated obligations and will rank equally in right of payment with all of our other unsecured and unsubordinated indebtedness, which at September 30, 2023 was approximately $11.2 billion, consisting of long-term debt and short-term debt. Because we are a holding company that conducts all of our operations through our subsidiaries, our ability to meet our obligations under the Notes is dependent on the earnings and cash flows of those subsidiaries and the ability of those subsidiaries to pay dividends to us, repurchase shares of their common stock from us or repay loans or advances made by us to them. Dividends payable by certain of our subsidiaries are restricted pursuant to the terms of the subsidiaries’ debt agreements and regulatory requirements, but we do not believe these restrictions should interfere with the payment of interest on or repayment of the Notes. Holders of the Notes will generally have a junior position to claims of any holders of preferred stock and creditors of our subsidiaries, including trade creditors, debt-holders, secured creditors, taxing authorities and guarantee holders. In addition to trade debt, our subsidiaries have ongoing corporate debt programs used to finance their respective business activities. As of September 30, 2023, our subsidiaries had approximately $14.9 billion of outstanding external debt for borrowed money, which included long-term debt (including approximately $808.4 million due within one year) and short-term debt, but did not include trade debt, capital leases, power purchase obligations, liability for prior period spent nuclear fuel disposal costs, and $155.6 million of outstanding preferred stock. The Senior Note Indenture does not currently limit the amount of indebtedness or preferred stock we or our subsidiaries may issue. Please refer to “Description of Securities Registered — Eversource Energy — Senior Notes — General” in the accompanying prospectus.

We will issue the Notes in fully registered form in minimum denominations of $2,000 and integral multiples of $1,000 thereafter. The Bank of New York Mellon Trust Company, N.A., the Trustee under the Senior Note Indenture, will register transfers and exchanges of the Notes and will serve as paying agent for the Notes. Principal on the Notes will be payable at the Trustee’s Corporate Trust Office which, at the date hereof, is located at 500 Ross Street, 12th Floor, Pittsburgh, Pennsylvania 15262. We will initially issue

The Notes will bear interest at the rate of     % per year. We will pay interest on the Notes semiannually in arrears on February 1 and August 1 of each year (each, a “Note Interest Payment Date”), beginning on February 1, 2024, and ending on the maturity date. Interest on the Notes shall be computed on the basis of a 360-day year consisting of twelve 30-day months and for any period less than a full month, on the basis of the actual number of days elapsed. If a Note Interest Payment Date or the maturity date of the Notes falls on a day that is not a business day, the payment of principal and interest will be made on the next succeeding business day (without any interest or other payment in respect of such delay).

Interest on the Notes will accrue from, and including, the date of original issuance of the Notes to, and excluding, the first Note Interest Payment Date and then from, and including, the immediately preceding Note Interest Payment Date to which interest has been paid or duly provided for to, but excluding, the next Note Interest Payment Date or the maturity date, as the case may be. In addition, principal and interest which is overdue shall bear interest at the rate of    % per year.

We will pay the interest due on any Note Interest Payment Date or the maturity date to the person in whose name the Notes are registered at the close of business (i) on the business day prior to each Note Interest Payment Date or the maturity date if the Note remains in book-entry only form or (ii) on the fifteenth calendar day before each Note Interest Payment Date or the maturity date if the Note does not remain in book-entry only form.

When we use the term “business day,” we mean any day except a Saturday, a Sunday or a legal holiday in New York, New York or in Pittsburgh, Pennsylvania on which banking institutions are authorized or required by law, regulation or executive order to close.

Prior to the Par Call Date (as defined below), we may redeem the Notes at our option, in whole or in part, at any time and from time to time, on not less than 10 nor more than 60 days’ prior written notice mailed (or delivered by electronic transmission in accordance with the applicable procedures of DTC) to the holders of the Notes at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

On or after the Par Call Date, we may redeem the Notes at our option, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the Notes being redeemed plus accrued and unpaid interest thereon to, but excluding, the redemption date.

“Par Call Date” means January 1, 2029 (the date that is one month prior to the maturity date of the Notes).

“Treasury Rate” means, with respect to any redemption date, the yield determined by us in accordance with the following two paragraphs.

The Treasury Rate shall be determined by us after 4:15 p.m., New York City time (or after such time as yields on U.S. government securities are posted daily by the Board of Governors of the Federal Reserve System), on the third business day preceding the redemption date based upon the yield or yields for the most

If on the third business day preceding the redemption date H.15 TCM is no longer published, we shall calculate the Treasury Rate based on the rate per annum equal to the semi-annual equivalent yield to maturity at 11:00 a.m., New York City time, on the second business day preceding such redemption date of the United States Treasury security maturing on, or with a maturity that is closest to the Par Call Date. If there is no United States Treasury security maturing on the Par Call Date but there are two or more United States Treasury securities with a maturity date equally distant from the Par Call Date, one with a maturity date preceding the Par Call Date and one with a maturity date following the Par Call Date, we shall select the United States Treasury security with a maturity date preceding the Par Call Date. If there are two or more United States Treasury securities maturing on the Par Call Date or two or more United States Treasury securities meeting the criteria of the preceding sentence, we shall select from among these two or more United States Treasury securities the United States Treasury security that is trading closest to par based upon the average of the bid and asked prices for such United States Treasury securities at 11:00 a.m., New York City time. In determining the Treasury Rate in accordance with the terms of this paragraph, the semi-annual yield to maturity of the applicable United States Treasury security shall be based upon the average of the bid and asked prices (expressed as a percentage of principal amount) at 11:00 a.m., New York City time, of such United States Treasury security, and rounded to three decimal places.

Our actions and determinations in determining the redemption price shall be conclusive and binding for all purposes, absent manifest error. The Trustee shall have no responsibility to calculate the redemption price.

Notice of any redemption will be mailed or electronically delivered (or otherwise transmitted in accordance with the depositary’s procedures) at least 10 days but not more than 60 days before the redemption date to each holder of the Notes to be redeemed.

In the case of a partial redemption, selection of the Notes for redemption will be made by lot or pursuant to the applicable depositary’s procedures. No Notes of a principal amount of $2,000 or less will be redeemed in part. If any Note is to be redeemed in part only, the notice of redemption that relates to such Note will state the portion of the principal amount of the Note to be redeemed. A new Note in a principal amount equal to the unredeemed portion of the Note will be issued in the name of the holder of the Note upon surrender for cancellation of the original Note. For so long as the Notes are held by DTC (or another depositary), the redemption of the Notes shall be done in accordance with the policies and procedures of the depositary.

On and after the redemption date interest will cease to accrue on the Notes or portions thereof called for redemption. Prior to any redemption date, we are required to deposit with a paying agent money sufficient to pay the redemption price of and accrued interest on the Notes to be redeemed on such date.

Any redemption may, at our discretion, be subject to one or more conditions precedent, including, but not limited to, the completion or occurrence of a related transaction or event, as the case may be, and any notice of redemption made in connection with a related transaction or event may, at our discretion, be given prior to the completion or the occurrence thereof. If such redemption is subject to satisfaction of one or

The covenants set forth in the accompanying prospectus under “Description of Securities Registered — Eversource Energy — Senior Notes — Limitation on Liens” and “Description of Securities Registered — Eversource Energy — Senior Notes — Sale and Leaseback Transactions” have been made applicable to the Notes.

We may defease the indebtedness on the Notes on the terms described under “Description of Securities Registered — Eversource Energy — Senior Notes — Defeasance” in the accompanying prospectus. In addition, we may defease the Notes within 60 days prior to maturity without delivering an opinion that the defeasance will not cause the holders of the Notes to recognize income, gain, loss or expense for United States federal income tax purposes. The purpose of this provision is to give us more flexibility in timing a refinancing of the indebtedness represented by the Notes. Such a defeasance would be treated as a taxable exchange for United States federal income tax purposes, as a result of which a holder could recognize gain or loss, and which could change the amounts, timing and character of any income, gain or loss recognized on the Notes following defeasance.

We may, from time to time, without giving notice or seeking the consent of the holders of the Notes, create and issue additional debt securities having the same terms (except for the issue date, the public offering price and, under certain circumstances, the first interest payment date) ranking equally and ratably with the Notes offered by this prospectus supplement, including having the same CUSIP number, so that such additional debt securities would be consolidated and form a single series with the Notes and would have the same terms as to status, redemption or otherwise as the Notes. No such additional debt securities may be issued if an Event of Default (as used and defined in the Senior Note Indenture) has occurred and is continuing with respect to the Notes.

When the Notes are initially issued, one or more global securities (the “Global Securities”) will represent the Notes. These Global Securities will have an aggregate principal amount equal to that of the Notes they represent. Each Global Security will be deposited with, or on behalf of, The Depository Trust Company, as depositary (DTC), and registered in the name of Cede & Co., a nominee of DTC.

The Global Securities will bear legends stating the restrictions on exchanges and registration of transfer referred to below and any other matters provided for by the Senior Note Indenture. Please refer to “Book- Entry; Delivery and Form; Global Securities” in the accompanying prospectus.

The Global Securities may not be transferred except as a whole (1) by DTC to a nominee of DTC or (2) by a nominee of DTC to DTC or another nominee of DTC or (3) by DTC or any such nominee to a successor of DTC or a nominee of such successor. If (1) DTC is at any time unwilling or unable to continue as depositary or at any time ceases to be a clearing agency registered as such under the Exchange Act and a successor depositary is not appointed by us within ninety days or (2) there shall have occurred and be

The following is a summary of certain anticipated United States federal income tax consequences of the purchase, ownership and disposition of Notes. Except where noted, this summary deals only with Notes held as capital assets by beneficial owners of the Notes who purchase Notes in this offering at the price listed on the cover of this prospectus supplement and does not address considerations applicable to holders of the Senior Notes, Series N. This summary is based upon the provisions of the Internal Revenue Code of 1986, as amended (the “Code”), regulations promulgated thereunder, and judicial and administrative rulings and decisions now in effect, all of which are subject to change or differing interpretations, possibly with retroactive effect. This summary does not purport to address all aspects of United States federal income taxation that may affect particular investors in light of their individual circumstances, or certain types of investors subject to special treatment under the United States federal income tax laws, such as persons that mark to market their securities, financial institutions, individual retirement and other tax-deferred accounts, tax-exempt organizations, broker-dealers, certain former U.S. citizens or long-term residents, life insurance companies, persons that hold Notes as part of a hedge against currency or interest rate risks or that hold Notes as part of a straddle, conversion transaction or other integrated investment. This summary does not address any aspect of state, local or foreign taxation.

For purposes of this summary, a “U.S. Holder” is a beneficial owner of a Note that is, for United States federal income tax purposes:

For purposes of this summary, a “Non-U.S. Holder” is a beneficial owner of a Note that is not a U.S. Holder or a partnership (including an entity or arrangement treated as a partnership for United States federal income tax purposes).

If a partnership (including an entity or arrangement treated as a partnership for United States federal income tax purposes) is a beneficial owner of Notes, the tax treatment of a partner will generally depend upon the status of the partner and the activities of the partnership. Partnerships (and partners in such partnerships) that are beneficial owners of Notes, should consult their tax advisors.

Barclays Capital Inc., Citigroup Global Markets Inc., J.P. Morgan Securities LLC, Morgan Stanley & Co. LLC, MUFG Securities Americas Inc., and U.S. Bancorp Investments, Inc. are acting as joint book-running managers of the offering and as representatives of the underwriters named below. Subject to the terms and conditions set forth in the underwriting agreement between us and the representatives on behalf of each of the underwriters named below with respect to the sale of the Notes, dated the date of this prospectus supplement, we have agreed to sell to each of the underwriters, and each of the underwriters have severally, but not jointly, agreed to purchase the principal amount of Notes set forth opposite its name below:

The underwriting agreement provides that the obligations of the underwriters pursuant thereto are subject to certain conditions and to approval of legal matters by counsel. The offering of the Notes by the underwriters is subject to the receipt and acceptance of, and subject to the underwriters’ right to reject, any order in whole or in part.

The underwriters have advised us that they initially propose to offer the Notes directly to the public at the public offering prices set forth on the cover page hereof and may offer the Notes to certain dealers at a price that represents a concession not in excess of    % of the principal amount of the Notes. The underwriters may allow, and any such dealers may re-allow, a concession to certain other dealers not in excess of    % of the principal amount of the Notes, on sales to other dealers. After the initial offering of the Notes, the public offering prices and other selling terms may from time to time be varied by the underwriters.

The following table shows the underwriting discount that we are to pay to the underwriters in connection with this offering (expressed as a percentage of the principal amount of the Notes).

We estimate that our expenses in connection with the offer and sale of the Notes, excluding underwriting discounts, will be approximately $2,140,000 and will be payable by us.

We have agreed to indemnify the several underwriters against, or contribute to payments the underwriters may be required to make in respect of, certain liabilities, including liabilities under the Securities Act of 1933, as amended.

We expect to deliver the Notes against payment for the Notes on or about the date specified in the last paragraph of the cover page of this prospectus supplement, which will be the second business day following the date of this prospectus supplement.

The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. The underwriters and certain of their affiliates have, from time to time, performed, and will continue to perform, various investment or commercial banking and financial advisory services for us and our affiliates in the ordinary course of business for which they have received and will receive customary compensation. Currently, certain of the underwriters, either directly or through affiliates, are lenders under certain Eversource Energy credit facilities.

In addition, in the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade 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, and such investment and securities activities may involve securities and/or instruments of ours and our affiliates. If any of the underwriters or their affiliates has a lending relationship with us, certain of these underwriters or their affiliates routinely hedge, and certain other of those underwriters or their affiliates may hedge, their credit exposure to us consistent with their customary risk management policies. Typically, these underwriters and their affiliates would hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities, including potentially the Notes. Any such credit default swaps or short positions could adversely affect future trading prices of the Notes. The underwriters and their respective affiliates may also make investment recommendations or publish or express independent research views in respect of such securities or instruments, and may at any time hold, or recommend to clients that they acquire, long or short positions in such securities and instruments.

This prospectus supplement, the accompanying prospectus or any other disclosure document (as defined in the Corporations Act 2001 (Cth) of Australia (the “Corporations Act”)) in relation to the Notes has not been or will not be lodged with the Australian Securities & Investments Commission (“ASIC”). This

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 Notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the European Economic Area (“EEA”). For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU (as amended, “MiFID II”); or (ii) a customer within the meaning of Directive (EU) 2016/97 (as amended, the “Insurance Distribution Directive”), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or not a qualified investor as defined in Regulation (EU) 2017/1129 (as amended, the “Prospectus Regulation”). Consequently, no key information document required by Regulation (EU) No 1286/2014 (as amended, the “PRIIPs Regulation”) for offering or selling the Notes or otherwise making them available to retail investors in the EEA has been prepared and therefore offering or selling the Notes or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPs Regulation. This prospectus supplement and the accompanying prospectus have been prepared on the basis that any offer of Notes in any Member State of the EEA will be made pursuant to an exemption under the Prospectus Regulation from the requirement to publish a prospectus for offers of Notes. This prospectus supplement and the accompanying prospectus are not a prospectus for the purposes of the Prospectus Regulation.

This prospectus supplement and the accompanying base prospectus have not been reviewed, approved or licensed by the Central Bank of the United Arab Emirates (the “UAE”), the Emirates Securities and

The Notes may not be offered or sold by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), or (ii) to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap.571, Laws of Hong Kong) and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a “prospectus” within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), and no advertisement, invitation or document relating to the Notes may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the laws of Hong Kong) other than with respect to Notes which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder.

The Notes have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (the Financial Instruments and Exchange Law) and each underwriter has agreed that it will not offer or sell any Notes, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the Financial Instruments and Exchange Law and any other applicable laws, regulations and ministerial guidelines of Japan.

The Notes have not been and will not be registered under the Financial Investment Services and Capital Markets Act and the decrees and regulations thereunder (the “FSCMA”) and the Notes have been and will be offered in Korea as a private placement under the FSCMA. None of the Notes may be offered, sold and delivered, directly or indirectly, or offered or sold to any person for re-offering or resale, directly or indirectly, in Korea or to any resident of Korea except as otherwise permitted under the applicable laws and regulations of Korea, including the FSCMA and the Foreign Exchange Transaction Law of Korea and the decrees and regulations thereunder (the “FETL”). For a period of one year from the issue date of the Notes, any acquirer of the Notes who was solicited to buy the Notes in Korea is prohibited from transferring any of the Notes to another person in any way other than as a whole to one transferee. Furthermore, the purchaser of the Notes shall comply with all applicable regulatory requirements (including but not limited to requirements under the FETL) in connection with the purchase of the Notes.

This prospectus supplement and the accompanying prospectus have not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus supplement and accompanying prospectus and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the Notes have not been and will not be circulated or distributed, nor have the Notes been or will the Notes be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore (the “SFA”), (ii) to a relevant person pursuant to Section 275(1), or any person pursuant to Section 275(1A), and in accordance with the conditions, specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA, in each case subject to compliance with conditions set forth in the SFA.

Where the Notes are subscribed or purchased under Section 275 of the SFA by a relevant person which is: (a) a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or (b) a trust (where the trustee is not an accredited

We make statements in this prospectus and in the documents we incorporate by reference that are statements concerning our expectations, beliefs, plans, objectives, goals, strategies, assumptions of future events, future financial performance or growth and other statements that are not historical facts. These statements are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. You can generally identify our forward-looking statements through the use of words or phrases such as “estimate,” “expect,” “anticipate,” “intend,” “plan,” “project,” “believe,” “forecast,” “should,” “could,” and other similar expressions. Forward-looking statements are based on the current expectations, estimates, assumptions or projections of management and are not guarantees of future performance. These expectations, estimates, assumptions or projections may vary materially from actual results. Accordingly, any such statements are qualified in their entirety by reference to, and are accompanied by, the following important factors that could cause our actual results to differ materially from those contained in our forward-looking statements, including, but not limited to:

Other risk factors are detailed from time to time in reports filed by the Registrants with the SEC and we encourage you to consult such disclosures.

All such factors are difficult to predict, contain uncertainties that may materially affect our actual results and are beyond the control of the Registrants. You should not place undue reliance on the forward-looking statements, each speaks only as of the date on which such statement is made, and, except as required by the federal securities laws, the Registrants undertake no obligation to update any forward-looking statement or statements 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

Eversource Energy also has an offshore wind business, which includes a 50 percent ownership interest in offshore wind projects that are being developed and constructed through a joint and equal partnership with Ørsted. Eversource Energy holds a 50 percent ownership interest in North East Offshore, LLC, which holds power purchase agreements (PPAs) and contracts for the Revolution Wind, South Fork Wind and Sunrise Wind projects, as well as offshore leases issued by the U.S. Bureau of Ocean Energy Management. This partnership also participates in new procurement opportunities for offshore wind energy in the Northeast U.S. The offshore leases include a 257 square-mile ocean lease off the coasts of Massachusetts and Rhode Island and a separate, adjacent 300 square-mile ocean lease located approximately 25 miles south of the coast of Massachusetts. In aggregate, these ocean lease sites jointly-owned by Eversource Energy and Ørsted could eventually develop at least 4,000 MW of clean, renewable offshore wind energy.

The principal executive office of Eversource Energy is located at 300 Cadwell Drive, Springfield, Massachusetts 01104. The general business offices of Eversource Energy are located at 800 Boylston Street, Boston, Massachusetts 02199 and 56 Prospect Street, Hartford, Connecticut 06103. Its telephone number is (800) 286-5000.

The Connecticut Light and Power Company, doing business as Eversource Energy (CL&P), a Connecticut corporation, is a wholly-owned subsidiary of Eversource Energy. CL&P is engaged in the purchase, transmission, delivery and sale of electricity to its residential, commercial and industrial customers. As of December 31, 2021, CL&P furnished retail franchise electric service to approximately 1.27 million customers in 149 cities and towns in Connecticut, covering an area of 4,400 square miles. CL&P does not own any electric generation facilities.

The principal executive and business offices of CL&P are located at 107 Selden Street, Berlin, Connecticut 06037, and its telephone number is (800) 286-5000.

NSTAR Electric Company, doing business as Eversource Energy (NSTAR Electric), a Massachusetts corporation, is a wholly-owned subsidiary of Eversource Energy. NSTAR Electric is engaged in the purchase,

We may issue warrants for the purchase of preferred shares, common shares, or any combination thereof. Warrants may be issued independently or together with other securities and may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a bank or trust company, as warrant agent. The warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation or relationship of agency or trust for us with any holders or beneficial owners of warrants.

This summary of certain provisions of the warrants is not complete. For the complete terms of the warrants and the warrant agreement, you should refer to the provisions of the warrant agreement that we will file with the SEC in connection with the offering of such warrants.

The applicable prospectus supplement will describe the following terms of any warrants in respect of which this prospectus is being delivered:

We and the warrant agent may amend or supplement the warrant agreement for a series of warrants without the consent of the holders issued thereunder to effect changes that are not inconsistent with the provisions of the warrants and that do not materially and adversely affect the interests of the holders of the warrants.

We may issue share purchase contracts, including contracts obligating holders to purchase from us, and us to sell to the holders, a specified number of common shares at a future date or dates. The price per common share and the number of common shares may be fixed at the time the share purchase contracts are issued or may be determined by reference to a specific formula set forth in the share purchase contracts. The share purchase contracts may be issued separately or as part of units consisting of a share purchase contract and beneficial interests in debt securities, preferred shares or debt obligations of third parties, including U.S.

The applicable prospectus supplement will describe the terms of the share purchase contracts or share purchase units, including, if applicable, collateral or depositary arrangements, relating to the share purchase contracts or share purchase units.

common shares or convertible securities released from preemptive rights through the affirmative vote or written consent of the holders of at least two-thirds of the common shares then outstanding; or

Another Massachusetts anti-takeover statute, Chapter 110D of the Massachusetts General Laws, regulates the acquisition of control shares. A control share acquisition occurs when an individual aggregates a number of shares which, when added to shares already owned, would allow the acquiring person to vote at least 20 percent of the Company’s shares. Under Chapter 110D, shares acquired in this type of a transaction would have no voting rights unless a majority of non-interested shareholders specifically voted to grant the acquiring person voting rights for these shares. In general, the acquiring person as well as our officers and employee-Trustees are not permitted to vote on whether these voting rights should be granted.

The Senior Note Trustee may be removed at any time by an instrument or concurrent instruments in writing delivered to the Senior Note Trustee and us and signed by the holders, or their attorneys-in-fact, of at least a majority in principal amount of the then outstanding Senior Notes. In addition, under certain circumstances, we may remove the Senior Note Trustee upon notice to the Holder of each Senior Note outstanding and the Senior Note Trustee, and appointment of a successor Senior Note Trustee. (Section 610)

Each holder of CL&P Bonds issued after 2003 (including any CL&P Bonds offered by any prospectus supplement and any CL&P Bonds offered by any future prospectus), solely by virtue of its acquisition of such CL&P Bonds, including as an owner of a book-entry or other beneficial interest therein, will have and be deemed to have consented, without the need for any further action or consent by such holder, to the B Provisions. We presently do not expect to receive the requisite 100 percent consent for the B Provisions, and therefore do not expect the B Provisions to become effective, until 2024, when the last series of CL&P Bonds outstanding issued before 2004 mature.

Accordingly, presented below are summary descriptions of the CL&P Bonds and the CL&P Indenture — as now in effect and as they will be in effect following receipt of the requisite bondholder consent, when the B Provisions become effective.

THERE ARE MATERIAL DIFFERENCES BETWEEN THE CL&P INDENTURE AS NOW IN EFFECT AND AS IT WILL BE IN EFFECT WHEN THE B PROVISIONS BECOME EFFECTIVE, AND YOU ARE ADVISED TO CAREFULLY READ THE SUMMARIES BELOW TO UNDERSTAND THE IMPACT OF THE B PROVISIONS. THE SUMMARY DESCRIPTION OF THE PROVISIONS OF THE CL&P INDENTURE AND OF THE B PROVISIONS WHICH FOLLOWS DOES NOT PURPORT TO BE COMPLETE OR TO COVER ALL OF THE PROVISIONS THEREOF. COPIES OF THE CL&P INDENTURE, INCLUDING THE B PROVISIONS, ARE AVAILABLE FROM US AND REFERENCE IS MADE TO THE CL&P INDENTURE, INCLUDING THE B PROVISIONS. FOR A COMPLETE STATEMENT OF THE APPLICABLE PROVISIONS, THE CL&P INDENTURE, INCLUDING THE B PROVISIONS, IS INCLUDED AS AN EXHIBIT TO THE REGISTRATION STATEMENT OF WHICH THIS PROSPECTUS IS A PART.

The CL&P Bonds are to be issued only in the form of fully registered bonds without coupons in denominations of $1,000 or multiples thereof and may be presented for exchange for a like aggregate principal amount of the same series of CL&P Bonds of other authorized denominations and for transfer at the principal office of the CL&P Bond Trustee in New York City without payment in either case of any charge other than for any tax or other governmental charges required to be paid by us.

The B Provisions would continue the existing first mortgage lien of the CL&P Indenture, but would expand both the types of property excepted from the lien and the types of permitted liens. We believe that these changes will not have a material effect on the security afforded by the mortgage lien on the property subject thereto. However, the B Provisions also would exclude any generating properties from the lien of the CL&P Indenture. Although this is not significant at present because we own no generating properties, if any such properties are acquired or constructed in the future, after effectiveness of the B Provisions, such properties would not be subject to the lien of the CL&P Indenture unless we chose to take such action.

Unlike the current provisions of the CL&P Indenture, the B Provisions would permit us to issue certain debt other than CL&P Bonds that would be secured by liens on the mortgaged property that are equal with or prior to the lien of the CL&P Indenture. We believe that this change will not have a material

We may issue debt securities as “original issue discount securities,” which bear either no interest or interest at a rate that at the time of issuance is below market rates. These securities will be sold at a substantial discount below their principal amount. In the event that the maturity of an original issue discount security is accelerated, the amount payable to the holder upon acceleration will be determined in accordance with the terms of that security and the NSTAR Electric Indenture, but will be an amount less than the amount payable at the stated maturity of the principal of the security. The prospectus supplement will describe special federal income tax and other considerations relating to original issue discount securities.

The covenants contained in the NSTAR Electric Indenture and the debt securities will not protect holders in the event of a sudden decline in our creditworthiness that might result from a recapitalization, restructuring, or other highly leveraged transaction.

default in the payment of any interest when due, which continues for 30 days;

any redemption or sinking fund terms;

Unless we indicate otherwise in the applicable prospectus supplement, The Depository Trust Company (DTC), New York, New York, will act as securities depository for the securities. The securities will be issued as fully-registered securities registered in the name of Cede & Co., DTC’s partnership nominee, or such other name as may be requested by an authorized representative of DTC. One fully-registered certificate will be issued for each issue of securities, each in the aggregate principal amount of any such issue, and will be deposited with DTC. If, however, the aggregate principal amount of any issue exceeds $500 million, one certificate will be issued with respect to each $500 million of principal amount, and an additional certificate will be issued with respect to any remaining principal amount of any such issue.

DTC, the world’s largest securities depository, is a limited-purpose trust company organized under the New York Banking Law, a “banking organization” within the meaning of the New York Banking Law, a member of the Federal Reserve System, a “clearing corporation” within the meaning of the New York Uniform Commercial Code and a “clearing agency” registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934. DTC holds and provides asset servicing for issues of U.S. and non-U.S. equity issues, corporate and municipal debt issues and money market instruments that DTC’s participants (Direct Participants) deposit with DTC. DTC also facilitates the post-trade settlement among Direct Participants of sales and other securities transactions in deposited securities, through electronic computerized book-entry transfers and pledges between Direct Participants’ accounts. This eliminates the need for physical movement of securities certificates. Direct Participants include both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations. DTC is a wholly-owned subsidiary of The Depository Trust & Clearing Corporation (DTCC). DTCC is the holding company for DTC, National Securities Clearing Corporation and Fixed Income Clearing Corporation, all of which are registered clearing agencies. DTCC is owned by the users of its regulated subsidiaries. Access to the DTC system is also available to others such as both U.S. and non-U.S. securities brokers and dealers, banks, trust companies and clearing corporations that clear through or maintain a custodial relationship with a Direct Participant, either directly or indirectly (Indirect Participants). The DTC Rules applicable to its Participants are on file with the SEC. More information about DTC can be found at www.dtcc.com. Information on www.dtcc.com is not incorporated by reference in this prospectus

Purchases of securities under the DTC system must be made by or through Direct Participants, which will receive a credit for the securities on DTC’s records. The ownership interest of each actual purchaser of each security (Beneficial Owner) is in turn to be recorded on the Direct and Indirect Participants’ records. Beneficial Owners will not receive written confirmation from DTC of their purchase. Beneficial Owners are, however, expected to receive written confirmations providing details of the transaction, as well as periodic statements of their holdings, from the Direct or Indirect Participant through which the Beneficial Owner entered into the transaction. Transfers of ownership interests in the securities are to be accomplished by entries made on the books of Direct and Indirect Participants acting on behalf of Beneficial Owners. Beneficial Owners will not receive certificates representing their ownership interests in securities, except in the event that use of the book-entry system for the securities is discontinued.

To facilitate subsequent transfers, all securities deposited by Direct Participants with DTC are registered in the name of DTC’s partnership nominee, Cede & Co., or such other name as may be requested by an authorized representative of DTC. The deposit of securities with DTC and their registration in the name of Cede & Co. or such other DTC nominee do not effect any change in beneficial ownership. DTC has no knowledge of the actual Beneficial Owners of the securities; DTC’s records reflect only the identity of the Direct Participants to whose accounts such securities are credited, which may or may not be the Beneficial Owners. The Direct and Indirect Participants will remain responsible for keeping account of their holdings on behalf of their customers.

Conveyance of notices and other communications by DTC to Direct Participants, by Direct Participants to Indirect Participants, and by Direct Participants and Indirect Participants to Beneficial Owners will be governed by arrangements among them, subject to any statutory or regulatory requirements as may be in effect from time to time. Beneficial Owners of securities may wish to take certain steps to augment the transmission to them of notices of significant events with respect to the securities, such as redemptions, tenders, defaults, and proposed amendments to the security documents. For example, Beneficial Owners of securities may wish to ascertain that the nominee holding the securities for their benefit has agreed to obtain

We may sell securities through one or more underwriters or dealers, directly to one or more purchasers, in a rights offering, in “at-the-market” offerings, within the meaning of Rule 415(a)(4) of the Securities Act of 1933, as amended (Securities Act), to or through a market maker or into an existing trading market or an exchange or otherwise, through agents, pursuant to forward contracts or through a combination of any of these sale methods, or through any other methods described in a prospectus supplement. The prospectus supplement relating to the securities being offered will set forth the terms of the offering and the method of distribution, including:

We may distribute the securities offered under this prospectus from time to time in one or more transactions at a fixed price or prices, which may be changed, at prevailing markets prices or at prices determined as the prospectus supplement specifies. We may sell securities through forward contracts or similar arrangements.

Securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. If we use underwriters for a sale of securities, we will enter into an underwriting agreement with the underwriters at the time of sale of those securities. Unless we inform you otherwise in a prospectus supplement, the obligations of the underwriters to purchase the offered securities will be subject to certain conditions and the underwriters will be obligated to purchase all of the offered securities if any are purchased. The underwriters will acquire the securities for their own account. The underwriters may resell the securities in one or more transactions at a fixed public offering price, at market prices prevailing at the time of sale, at prices related to such prevailing market prices or at negotiated prices. The underwriters may change from time to time any initial public offering price and any discounts or concessions allowed or re-allowed or paid to dealers. Only those underwriters identified in the prospectus supplement are deemed to be underwriters in connection with the securities offered in the prospectus supplement.

If we use dealers in a sale, unless we inform you otherwise in a prospectus supplement, we will sell the securities to the dealers as principals.

The dealers may then resell such securities to the public at varying prices that they determine at the time of resale.

We may sell the securities directly. In this case, no underwriters or agents would be involved. We may also sell the securities through agents designated from time to time. In the prospectus supplement, we will name any agent involved in the offer or sale of the offered securities, and we will describe any commissions payable to the agent. Unless we inform you otherwise in the prospectus supplement, any agent will agree to use its reasonable best efforts to solicit purchases for the period of its appointment.

We may sell the securities directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act with respect to any sale of those securities. We will describe the terms of any sales of these securities in the prospectus supplement.

In connection with the sale of securities, underwriters, dealers or agents may be deemed to have received compensation from us in the form of underwriting discounts or commissions and also may receive commissions from securities purchasers for whom they may act as agent.

Underwriters, dealers and agents participating in the securities distribution may be deemed to be underwriters, and any discounts and commissions they receive and any profit they realize on the resale of the securities may be deemed to be underwriting discounts and commissions under the Securities Act. Underwriters, and their controlling persons, and agents may be entitled, under agreements we enter into with them, to indemnification against certain civil liabilities, including liabilities under the Securities Act. Some of the underwriters, dealers or agents and some of their affiliates who participate in the securities distribution may engage in other transactions with, and perform other services for, us and our subsidiaries or affiliates in the ordinary course of business.

In order to facilitate an offering of securities, persons participating in the offering may engage in transactions that stabilize, maintain or otherwise affect the price of the offered securities. Such transactions, if commenced, may be discontinued at any time. If any such activities will occur, they will be described in the applicable prospectus supplement.

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

Unless otherwise noted in the applicable prospectus supplement, legal opinions relating to the validity of the securities will be given by Ropes & Gray LLP, Boston, Massachusetts and Kerry J. Tomasevich, Esq., Assistant General Counsel of Eversource Energy Service Company and Assistant Secretary of Eversource Energy. We currently anticipate that Choate, Hall & Stewart LLP, Boston, Massachusetts, will pass on certain matters with respect to the securities registered for any underwriters, agents or dealers.

The financial statements of Eversource Energy incorporated by reference in this Prospectus, and the effectiveness of Eversource Energy’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 upon their authority as experts in accounting and auditing.

The financial statements of The Connecticut Light and Power Company incorporated by reference in this Prospectus, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report. Such financial statements are incorporated by reference in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

The financial statements of NSTAR Electric Company incorporated by reference in this Prospectus, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report. Such financial statements are incorporated by reference in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

The financial statements of Public Service Company of New Hampshire and subsidiary incorporated by reference in this Prospectus, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report. Such financial statements are incorporated by reference in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.