SUPPLEMENTAL INDENTURE

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Exhibit 4.2

PUBLIC SERVICE COMPANY
OF NEW HAMPSHIRE
AND
WACHOVIA BANK, NATIONAL ASSOCIATION

Successor to FIRST UNION NATIONAL BANK

Formerly Known as FIRST FIDELITY BANK, NATIONAL ASSOCIATION,
NEW JERSEY

Successor to BANK OF NEW ENGLAND, NATIONAL ASSOCIATION
(Formerly Known as NEW ENGLAND MERCHANTS NATIONAL BANK)
and to
NEW BANK OF NEW ENGLAND, NATIONAL ASSOCIATION, TRUSTEE

                        SUPPLEMENTAL INDENTURE
Dated as of            , 2004

TO ISSUE SERIES   
FIRST MORTGAGE BONDS

$    ,000,000 First Mortgage Bonds (Series    )

TABLE OF CONTENTS

Testimonium
Signatures

Schedule A—Form of Series    Bonds
Schedule B—Description of Certain Properties Acquired Since            .
Acknowledgments
Endorsement

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        THIS                        SUPPLEMENTAL INDENTURE dated as of                        , 20    , between PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE (hereinafter with its successors and assigns generally called the Company), a corporation duly organized and existing under the laws of The State of New Hampshire, having its principal place of business at 780 North Commercial Street in Manchester, New Hampshire 03101, and WACHOVIA BANK, NATIONAL ASSOCIATION, successor to First Union National Bank, formerly known as First Fidelity Bank, National Association, New Jersey, successor to Bank of New England, National Association (formerly known as New England Merchants National Bank) and to New Bank of New England, National Association, said Wachovia Bank, National Association (hereinafter with its successors generally called the Trustee), being a national banking association duly organized and existing under the laws of the United States of America, having acorporate trust office at 21 South Street, Third Floor, Morristown, New Jersey 07960, and duly authorized to execute the trusts hereof.

        WHEREAS, the Company heretofore duly executed and delivered to Bank of New England, National Association (formerly known as New England Merchants National Bank), as predecessor trustee, its General and Refunding Mortgage Indenture (hereinafter, as amended by the Tenth Supplemental Indenture dated as of May 1, 1991, generally referred to as the "Original Indenture" and sometimes referred to, with each and every prior indenture supplemental thereto and each and every other instrument, including this                        Supplemental Indenture, which the Company, pursuant to the provisions thereof, may execute with the Trustee and which is therein stated to be supplemental to the Original Indenture, as the "Indenture"), dated as of August 15, 1978, but actually executed on September 20, 1978, and recorded, among other places, in Hillsborough County, New Hampshire, Registry of Deeds, Book 2640, Page 334, in York County, Maine, Registry of Deeds, Book 2417, Page 01, in Concord, Vermont, Land Records, Book 44, Page 129A, and in the Office of the Secretary of the State of Connecticut in Volume 56, Page G of Railroad Mortgages (together with certificates with respect thereto recorded in the Town Clerk's offices of Waterford and Berlin, Connecticut), to which this instrument is supplemental, and in modification and confirmation thereof has executed and delivered to (i) Bank of New England, National Association (formerly known as New England Merchants National Bank) as predecessor trustee nine duly recorded indentures supplemental thereto, and (ii) to First Fidelity Bank, National Association, New Jersey, a Tenth Supplemental Indenture dated as of May 1, 1991 (hereinafter generally referred to as the Tenth Supplemental Indenture) thereto duly recorded, whereby substantially all the properties of the Company used by it in its business, whether then owned or thereafter acquired, with certain reservations, exceptions and exclusions fully set forth in the Original Indenture were given, granted, bargained, sold, transferred, assigned, pledged, mortgaged and conveyed to the Trustee, its successors and assigns, in trust upon the terms and conditions set forth therein to secure its General and Refunding Mortgage Bonds issued and to be issued thereunder, and for other purposes more particularly specified therein; and

        WHEREAS, on January 6, 1991, Bank of New England, National Association was declared insolvent, and New Bank of New England, National Association, pursuant to a purchase and assumption agreement dated as of January 6, 1991 between it and the Federal Deposit Insurance Corporation as receiver of Bank of New England, National Association, acquired and succeeded to all of the right, title, interest, authority and appointment of Bank of New England, National Association, as Trustee under the Indenture, which succession and appointment were ratified and confirmed by the Board of Directors of the Company on February 21, 1991, all as more particularly recited in the Agreement as to Resignation of Trustee and Appointment of Successor Trustee (the "Resignation and Appointment Agreement"), by and among the Company, New Bank of New England, National Association, and First Fidelity Bank, National Association, New Jersey, recorded with the Tenth Supplemental Indenture; and

        WHEREAS, pursuant to the Resignation and Appointment Agreement, New Bank of New England, National Association resigned as successor trustee and First Fidelity Bank, National Association, New Jersey succeeded to the trusts created by the Indenture; and

        WHEREAS, First Fidelity Bank, National Association, New Jersey was succeeded by First Union National Bank; and

        WHEREAS, pursuant to The Third Amended Joint Plan of Reorganization (the "Plan"), dated December 28, 1989 (Case No. 88-00043), as confirmed by order of the United States Bankruptcy Court for the District of New Hampshire dated April 20, 1990, all bonds outstanding under the First Mortgage Indenture dated as of January 1, 1943, as from time to time amended and supplemented, between the Company and Old Colony Trust Company, as trustee (to which each of The First National Bank of Boston and Maryland National Bank has been successor trustee) have been paid in full and said First Mortgage Indenture has been released and is of no further force or effect, all bonds outstanding under the Third Mortgage Indenture dated as of February 15, 1986, as from time to time amended and supplemented, between the Company and First Fidelity Bank, National Association, New Jersey, as trustee, have been paid in full and said Third Mortgage Indenture has been released and is of no further force or effect, and all bonds issued prior to the date of execution of the Tenth Supplemental Indenture and outstanding under the Indenture have been paid in full; and

        WHEREAS, the actions contemplated by the Resignation and Appointment Agreement and the Tenth Supplemental Indenture have been authorized and directed by Order of the United States Bankruptcy Court for the District of New Hampshire dated January 18, 1991 in Case No. 88-00043, which Order authorized certain transactions and procedures necessary to consummate the Plan and approved certain modifications of the Plan related thereto; and

        WHEREAS, all applicable requirements of the Plan and said Order have been complied with; and

        WHEREAS, pursuant to the Tenth Supplemental Indenture the Company effected the amendments to the Indenture specified in the Tenth Supplemental Indenture, including amendments to reflect the release and discharge of the Company's First Mortgage Indenture dated as of January 1, 1943, as supplemented and amended, and to reflect that, as a result, the Indenture is now a First Mortgage Indenture, the bonds issued and to be issued under the Indenture will be First Mortgage Bonds of the Company, and the Original Indenture as it may heretofore and hereafter be supplemented and amended shall henceforth be known and referred to as the Company's First Mortgage Indenture dated as of August 15, 1978; and

        WHEREAS, the Company by appropriate and sufficient corporate action in conformity with the terms of the Indenture duly caused to be issued seven new series of bonds under the Indenture designated First Mortgage Bonds, Series A through G, said Series A through Series G Bonds being in an aggregate principal amount of $858,985,000 and consisting of fully registered bonds containing the terms and provisions duly fixed and determined by the Board of Directors of the Company and expressed in Schedule B to the Tenth Supplemental Indenture; and

        WHEREAS, on May 15, 1996, $172,500,000 aggregate principal amount of the Company's 8 ⁷ / 8 % First Mortgage Bonds, Series A, matured and were paid and canceled; and

        WHEREAS, as of April 1, 1998 the Company by appropriate and sufficient corporate action in conformity with the terms of the Indenture duly caused to be issued a new series of bonds under the Indenture designated as First Mortgage Bonds, Series H, said Series H Bonds being in an aggregate principal amount of $75,000,000 and containing the terms and provisions duly fixed and determined by the Board of Directors of the Company and expressed in Schedule A to the Eleventh Supplemental Indenture; and

        WHEREAS, on May 15, 1998, $170,000,000 aggregate principal amount of the Company's 9.17% First Mortgage Bonds, Series, B, matured and were paid and canceled; and

        WHEREAS, on April 22, 1999, the Revolving Credit Agreement dated as of April 23, 1998 (the "Credit Agreement") terminated, the Credit Borrowings thereunder were indefeasibly paid in full in accordance with the terms thereof and the obligations of the several Lenders to make advances to the Company under the Credit Agreement were terminated; the bonds of Series H were deemed paid and all obligations of the Company to pay the principal of, premium, if any, and interest on the bonds of

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Series H was satisfied and discharged; and the $75,000,000 aggregated principal amount of the Company's First Mortgage Bonds, Series H, were canceled; and

        WHEREAS, as of March 30, 2001 the Company sold its interest in the Millstone II Nuclear Generating Station, located in Waterford, Connecticut, and with the sale of said property, no longer owns any property located in Connecticut which is subject to the lien of the Indenture, and is no longer subject to the jurisdiction of the Connecticut Department of Public Utilities Control; and

        WHEREAS, pursuant to the Series A, B and C Loan and Trust Agreements dated October 1, 2001 (herein called the "Series A, B and C PCRB Agreements"), by and among the Business Finance Authority of the State of New Hampshire (herein called "the Authority"), the Company and the State Street Bank and Trust Company, as trustee (herein called the "Series A, B and C PCRB Trustee"), the Authority issued concurrently: $89,250,000 in principal amount of its Pollution Control Revenue Bonds (Public Service Company of New Hampshire Project—2001 Tax Exempt Series A)(herein called the "Series A PCR Bonds") and loaned the proceeds from the sale of the Series A PCR Bonds to the Company. Proceeds of the loan were used to refund (i) the Authority's $66,000,000 aggregate principal amount 7.65% Pollution Control Revenue Bonds (Public Service Company of New Hampshire Project—1991 Tax-Exempt Series A)(the "1991 Series A Bonds"), and (ii) a portion of the Authority's $112,500,000 aggregate principal amount 7.65% Pollution Control Revenue Bonds (Public Service Company of New Hampshire Project—1991 Tax-Exempt Series C)(the "1991 Series C Bonds"); $89,250,000 in principal amount of its Pollution Control Revenue Bonds (Public Service Company of New Hampshire Project—2001 Tax-Exempt Series B) (herein called the "series B PCR Bonds") and loaned the proceeds from the sale of the Series B PCR Bonds to the Company. Proceeds of the loan were used to refund a portion of the 1991 Series C Bonds; and $108,985,000 in principal amount of its Pollution Control Revenue Bonds (Public Service Company of New Hampshire Project—2001 Tax Exempt Series C) (herein called the "Series C PCR Bonds") and loaned the proceeds from the sale of the Series C PCR Bonds to the Company. Proceeds of the loan were used to refund the Authority's $108,985,000 aggregate principal amount 7.50% Pollution Control Revenue Bonds (Public Service Company of New Hampshire Project—1991 Tax-Exempt Series B)(the "1991 Series B Bonds"). The proceeds of the 1991 Series A, B and C PCR Bonds were used to finance and refinance a portion of the Company's share of expenditures, including financing costs, relating to the construction of certain pollution control, sewage and/or solid waste disposal facilities required for the operation of the Seabrook nuclear-fueled, steam electric generating plant located in Seabrook, New Hampshire, in which the Company owned and undivided 35.6% interest; and

        WHEREAS, the Series A, B and C Bonds were special obligations of the Authority, payable solely out of the revenues and other receipts, funds and moneys derived by the Authority under the Series A, B and C Agreements and from any amounts otherwise available under the Series A, B and C Agreements for the payment of the Series A, B and C Bonds, and such revenues and other receipts, funds moneys and amounts are, pursuant to the Series A, B and C PCRB Agreements, assigned and pledged by the Authority to the Series A, B and C PCRB Trustee as security for the Series A, B and C PCR Bonds and include loan payments required to be made by the Company to the Series A, B and C PCRB Trustee for the account of the Authority pursuant to the Series A, B and C PCRB Agreements in amounts equal to the amounts payable with respect to the Series A, B and C Bonds; and

        WHEREAS, in consideration of the loan being provided by the Authority under, and pursuant to the provisions of, the Series A, B and C PCRB Agreements, the Company issued: $89,250,000 principal amount of its First Mortgage Bonds, Series I (hereinafter generally referred to as the "Series I Bonds" or the "bonds of Series I") to evidence and secure the Company's obligation under the Series A PCRB Agreement to make loan payments as aforesaid and to provide security for the Series A PCR Bonds; $89,250,000 principal amount of its First Mortgage Bonds, Series J (hereinafter generally referred to as the "Series J Bonds" or the "bonds of Series J") to evidence and secure the Company's obligation under the Series B PCRB Agreement to make loan payments as aforesaid and to provide security for

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the Series B PCR Bonds; and $108,985,000 principal amount of its First Mortgage Bonds, Series K (hereinafter generally referred to as the "Series K Bonds" or the "bonds of Series K") to evidence and secure the Company's obligation under the Series C PCRB Agreement to make loan payments as aforesaid and to provide security for the Series C PCR Bonds; and

        WHEREAS, the execution and delivery of the Twelfth Supplemental Indenture and the issue of not exceeding Eighty Nine Million Two Hundred Fifty Thousand Dollars ($89,250,000) in aggregate principal amount of bonds of Series I, Eighty Nine Million Two Hundred Fifty Thousand Dollars ($89,250,000) in aggregate principal amount of bonds Series J and One Hundred Eight Million Nine Hundred Eighty Five Thousand Dollars in aggregate principal amount of bonds of Series K, and other necessary actions were duly authorized by the Executive Committee of the Board of Directors of the Company; and

        WHEREAS, as a result of a merger, First Union National Bank changed its name to Wachovia Bank, National Association and remains as Trustee under the Indenture; and

        WHEREAS, the Company has purchased, constructed or otherwise acquired certain additional property not heretofore specifically described in the Indenture but which is and is intended to be subject to the lien thereof, and proposes specifically to subject such additional property to the lien of the Indenture at this time; and

        WHEREAS, the execution and delivery of this                        Supplemental Indenture and the issue of not exceeding            Million Dollars ($    ,000,000) in aggregate principal amount of bonds of Series    , and other necessary actions have been duly authorized by the Board of Directors of the Company; and

        WHEREAS, the Company proposes to execute and deliver this Supplemental Indenture to provide for the issue of the bonds of Series    and confirm the lien of the Indenture on the property referred to below, all as permitted by Section 15.1 of the Original Indenture; and

        WHEREAS, all acts and things necessary to make the initial issue of the Series    Bonds, when executed by the Company and authenticated by the Trustee and delivered as in the Original Indenture provided, the legal, valid and binding obligations of the Company according to their terms and to make this                        Supplemental Indenture a legal, valid and binding instrument for the security of the bonds, in accordance with its and their terms, have been done and performed, and the execution and delivery of this                        Supplemental Indenture has in all respects been duly authorized;

        NOW, THEREFORE, in consideration of the premises, and of the acceptance of said Series    First Mortgage Bonds by the holder thereof, and of the sum of $1.00 duly paid by the Trustee to the Company, and of other good and valuable considerations, the receipt whereof is hereby acknowledged, and in confirmation of and supplementing the Original Indenture as previously supplemented by said twelve preceding supplemental indentures, and in performance of and compliance with the provisions thereof, said Public Service Company of New Hampshire, by these presents, does give, grant, bargain, sell, transfer, assign, pledge, mortgage and convey unto Wachovia Bank, National Association, as Trustee, as provided in the Original Indenture, as previously supplemented and amended and as supplemented by this                        Supplemental Indenture, and its successor or successors in the trust thereby and hereby created, and its and their assigns, (a) all and singular the property, and rights and interests in property, described in the Original Indenture and the twelve preceding supplemental indentures (said supplemental indentures, in each case as amended by the Tenth Supplemental Indenture, hereinafter referred to as the Preceding Supplemental Indentures), and thereby conveyed, pledged, assigned, transferred and mortgaged, or intended so to be (said descriptions in said Original Indenture and the Preceding Supplemental Indentures being hereby made a part hereof to the same extent as if set forth herein at length), whether then or now owned or thereafter or hereafter acquired, except such of said properties or interests therein as may have been released or sold or disposed of in

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whole or in part as permitted by the provisions of the Original Indenture, and (b) also, but without in any way limiting the generality of the foregoing, all the right, title and interest of the Company, now owned or hereafter acquired, in and to the rights, titles, interests and properties described or referred to in Schedule B hereto attached and hereby made a part hereof as fully as if set forth herein at length, in all cases not specifically reserved, excepted and excluded; the foregoing pro