Interstate 495 was built in segments between 1958 and 1982.1 The route ended at Interstate 95 in Foxborough from the north until June 17, 1975, when the American Association of State Highway and Transportation Officials (AASHTO) approved the southeasterly extension to Interstate 195 at Wareham. This extension was previously approved by the Federal Highway Administration (FHWA) on May 23, 1974.
With mileage gained from the cancellations of both I-95 along the Southwest and Northeast Expressways through Boston, and the Inner Belt Expressway for I-695, the I-495 extension was added to the Interstate Highway System under the provisions of 23 U.S.C. 139(a) and 23 U.S.C. 139(e)(2). 14.2 miles of new construction lengthened I-495 southeast from Foxborough to the junction of Route 24/25 at Raynham. I-495 superseded an 18.5 mile long section of Route 25 from Raynham southeast to Middleborough and I-195 in Wareham. Interchanges were renumbered to start at Wareham instead of Foxborough.1