Massachusetts State Highway System

Standard highway shields
System information
Notes:	Routes are not always state-maintained, and not all state highways are Routes.
Highway names
Interstates:	Route I-X or Route X
US Highways:	Route US X or Route X
State:	Route X
System links
Massachusetts State Highway System Interstate US State

In the U.S. state of Massachusetts, the highway division of the Massachusetts Department of Transportation (MassDOT) assigns and marks a system of state-numbered routes. U.S. Highways and Interstate Highways are included in the system; the only overlaps are with the end-to-end U.S. Route 3 and Route 3 and the far-apart Interstate 295, shared with Rhode Island, and Route 295, shared with New York State. A state highway in Massachusetts is a road maintained by the state, which may or may not have a number. Not all numbered routes are maintained or owned by the state.

The Massachusetts Highway Commission (MHC) was the first highway commission in the U.S., formed in 1893 in response to a commission of inquiry finding that over 90% of the public roads in the state were in poor condition. The first state highway in Massachusetts was a 5305.17-foot (1617.02 m) section of Fitchburg Road (now Main Street, part of Route 119) in Ashby. The MHC laid it out as a state highway on August 15, 1894 from a point west of South Road to a point west of Route 31. The road was paved with 15–20 foot (4.5–6 m) macadam, with work beginning August 21, 1894 and ending July 15, 1895. The 50–66 foot (15–20 m) right-of-way is still owned by MassDOT under the original layout.

Massachusetts first gained numbered routes in 1922, with the formation of the New England Interstate Highways. Three-digit numbers were reserved for shorter routes. Route 138 and Route 140 were designated by 1925, and by 1926 the numbers from Route 101 to Route 142 (except Route 136) had been assigned.