Eighty-Seventh Supplemental Indenture

ANY WRITING, TEXT, INITIALS, REVISIONS OR NOTARY SEAL APPEARING OUTSIDE THESE MARGINS MAY DISQUALIFY THIS DOCUMENT FOR RECORDING

THIS EIGHTY-SEVENTH SUPPLEMENTAL INDENTURE, made as of the 29th day of April, 2009, by and between Puget Sound Energy, Inc., formerly Puget Sound Power & Light Company, a corporation duly organized and existing under and by virtue of the laws of the State of Washington (hereinafter sometimes called the “Company”), party of the first part, and U.S. Bank National Association, a national banking association with a principal corporate trust office at 100 Wall Street, Suite 1600, in the city of New York and State of New York 10005 (successor to Old Colony Trust Company) (hereinafter sometimes called the “Trustee”), as Trustee under the First Mortgage (originally, and before modification thereof by certain supplemental indentures, called “First and Refunding Mortgage”) from Puget Sound Power & Light Company, a Massachusetts corporation (hereinafter sometimes called the “Predecessor Company”), dated as of June 2, 1924 (said Mortgage being hereinafter sometimes called the “Original Mortgage”), as supplemented and modified by all indentures supplemental thereto heretofore executed and delivered, party of the second part;

WITNESSETH: that

WHEREAS, the Predecessor Company did by the Original Mortgage, filed for record in the offices of the Auditors of the Counties of Chelan, Clallam, Cowlitz, Douglas, Grant, Grays Harbor, Island, Jefferson, King, Kitsap, Kittitas, Lewis, Mason, Pacific, Pierce, Skagit, Snohomish, Thurston and Whatcom, all in the State of Washington, and left on file as a chattel mortgage in each of said counties, convey and pledge certain property therein described to Old Colony Trust Company, as Trustee, to be held upon the trusts expressed in the Original Mortgage to equally secure an unlimited authorized amount of mortgage bonds (therein and herein called the “Bonds”) issued or to be issued in one or more series, all as more fully provided in the Original Mortgage; and

WHEREAS, the Predecessor Company, prior to September 1, 1954, had executed and delivered to the Trustee thirty-nine supplemental indentures, supplementing and in certain respects modifying the Original Mortgage and providing for the execution, certification and delivery of Bonds of various series from time to time pursuant thereto (which Original Mortgage, as so supplemented and modified, is therein and herein sometimes called the “First Mortgage”); and

WHEREAS, the Predecessor Company executed and delivered to the Trustee a Fortieth Supplemental Indenture, dated as of September 1, 1954, which Supplemental Indenture is divided into two parts, designated as Part I and Part II, and Part I thereof provided for the establishment and the execution, certification and delivery initially of Twenty-Five Million Dollars ($25,000,000) principal amount of a series of Bonds, designated

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as First Mortgage Bonds, 3-1/2% Series due 1984, and contained certain covenants, restrictions, conditions and provisions affecting, and provided for certain modifications of, the First Mortgage (the First Mortgage, as so supplemented and modified by said Part I, being sometimes in said Fortieth Supplemental Indenture and herein called the “Revised First Mortgage”) and Part II thereof provided for modifications of the Revised First Mortgage as therein set forth, which modifications became effective on October 20, 1955 (the Revised First Mortgage as so modified by Part II of the Fortieth Supplemental Indenture as heretofore, hereby, and hereafter supplemented and modified being sometimes in said Part II and herein called the “Indenture” and references herein to Sections, Articles or other provisions of the Indenture being to the revised or modified provisions thereof as set forth in Part II of the Fortieth Supplemental Indenture); and

WHEREAS, the Predecessor Company has heretofore executed and delivered to the Trustee a Forty-First Supplemental Indenture dated as of December 1, 1954, a Forty-Second Supplemental Indenture dated as of July 1, 1957, a Forty-Third Supplemental Indenture dated as of May 1, 1958, a Forty-Fourth Supplemental Indenture dated as of November 1, 1959, and a Forty-Fifth Supplemental Indenture dated as of April 1, 1960, all of which mortgaged, pledged, assigned, conveyed and transferred to the Trustee and subjected to the lien of the Indenture additional property acquired or constructed, and betterments, improvements and additions made to the mortgaged property, since the execution and delivery of the Fortieth Supplemental Indenture; and

WHEREAS, the Company has executed and delivered to the Trustee a Forty-Sixth Supplemental Indenture dated as of November 10, 1960, whereby the Company has succeeded to the Predecessor Company with the same effect as if the Company had been named in the Indenture as the mortgagor company and in the Bonds and coupons as the obligor thereon or maker thereof, and the Predecessor Company merged into the Company on November 16, 1960, whereupon the Company acquired all the property, real, personal or mixed, including all rights, privileges, easements, licenses and franchises, described in the Indenture and thereby conveyed and mortgaged or intended so to be, including also all such property acquired by the Predecessor Company since the execution and delivery of the Original Mortgage, which by the terms of the Indenture is subjected or intended to be subjected to the lien thereof; and

WHEREAS, the Company has executed and delivered to the Trustee the supplemental indentures set forth herein:

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all of which mortgaged, pledged, assigned, conveyed and transferred to the Trustee and subjected to the lien of the Indenture additional property acquired or constructed, and betterments, improvements and additions made to the mortgaged property since the execution and delivery of the Fortieth Supplemental Indenture; and

WHEREAS, all Bonds of any series heretofore executed, authenticated and delivered pursuant to the Original Mortgage, as from time to time supplemented and modified, have been retired and canceled or payment duly and irrevocably provided for, except for the series set forth herein:

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