Signage

Signs installed before Interstate 95 was moved onto Route 128 in the 1970s prominently displayed the Route 128 designation. Even though it was built to freeway standards, Route 128 was never initially intended to be part of the Interstate system. The left sign was an overhead on Route 9 westbound for the interchange with 128 in Wellesley. This sign was replaced in 2009 with one indicating only the I-95 designation. The right sign was located on Washington Street approaching Elm Street in Dedham, and has since been removed. Signage on Interstate 90 - the Massachusetts Turnpike - clearly shows both routes. Westbound Exit 15 signage also shows both routes, and the signs remain present. After I-95 was moved to Route 128, new signs instead featured only that designation, with Route 128 marked only on separate sign assemblies. The left signage is present on US-1 northbound at its junction with I-95 (Exits 15A-B) in Dedham. The right signage is present on Walnut Street in Lynnfield, at the Exit 43 ramps to/from I-95. Other than on the Mass Pike, the only overhead signs to include both I-95 and Route 128 are near their northern split in Peabody. All signage in both directions for the I-95/Route 128 split was replaced in 2009 with I-95 the sole designation south of the split (with ground signage for 128 present). The right signage (at Exit 44 southbound) is the only remaining overhead on I-95 showing the Route 128 designation. The overhead sign on U.S. Route 1 north at the exit to Route 128 in Lynnfield, near the split in Peabody, originally indicated both directions of Route 128. (I-95 is only marked south because a more direct ramp to I-95 north exists straight ahead.) A standard sign assembly for Route 128 south was also installed. When the above sign was replaced in 2003 or 2004, Route 128 south was removed. Overhead signage on the ramp from US 1 north to Route 128 similarly only shows Route 128 north. Until 1997, Route 128's south end was at the Braintree Split in Braintree. Several signs for Route 3 in that area still indicated that in 2001. Sign upgrade projects on Route 128

As of the end of 2011, the state is between resigning projects on Route 128 that are replacing the 25-year-old signs with new exit, regulatory and route signs. Starting in 1998 and continuing through 2002, signs were replaced through a $1.1 million project between Reading and Lynnfield. Progress continued in 2005 and 2006 during a $2.2 million project which replaced the signs on from Peabody to Gloucester, and continued with a $1.4 million project in 2008 and 2009 that replaced signs in Peabody and the remaining ones in Lynnfield. A $2.9 million federal stimulus project helped replace exit and highway signs in 2010 and 2011 along Route 128 from US-3 in Lexington to I-93 in Reading.

A project valued at $4.5 million is expected to begin in the Fall of 2012 that will replace exit & guide signs on Route 128 from Route 9 (Exit 20) in Wellesley to Routes 4/225 (Exit 31) in Lexington. And starting in Summer 2014 a new project is to replace a variety of signs from Highland Avenue in Needham to Route 109 in Dedham. New signage was put up between I-95 and US 1 in 2010 and most of the signage between I-95 and Route 24 has been replaced as of December 2011. New mileage markers were placed every 2/10 of a mile along the highway in 2010 (except for the area covered by the widening project) for I-93 between Braintree and Canton and I-95 from Canton to Peabody. New markers put along Route 128 from Peabody to Gloucester reflect the state highway's total mileage from Canton, indicating MassDOT's change of heart in decommissioning the route where it shares the road with I-95. The previous mile markers (reflected in the exit list below) had mile 0 in Peabody.