The MBTA Commuter Rail system serves as the commuter rail arm of the Massachusetts Bay Transportation Authority's (MBTA's) transportation coverage of Greater Boston in the United States. Trains run over of track on 12 lines to 143 stations. It is operated under contract by Keolis.
In , the system had a ridership of , or about per weekday as of , making it the fifth-busiest commuter rail system in the U.S., behind the three New York-area systems and the Chicago-area system. The lines' characteristic purple-trimmed coaches operate as far south as North Kingstown, Rhode Island, and as far north as Newburyport and as far west as Fitchburg, both in Massachusetts.
Trains originate at two major terminals in Boston – South Station and North Station. The only connection between the two halves of the system is the non-revenue Grand Junction Branch. The North–South Rail Link is a proposed tunnel between North Station and South Station to allow through-running service. Passengers currently connect between the stations using MBTA subway service.
Service
Lines
The system consists of twelve lines – four of which have branches – radiating from downtown Boston. Eight "southside" lines terminate at South Station, with four (Framingham/Worcester, Needham, Franklin/Foxboro, and Providence/Stoughton) also running through Back Bay station. Four "northside" lines terminate at North Station. The lines vary in length from the Fairmount Line to the Providence/Stoughton Line, with typical lengths in the range.
|-
|Greenbush Line
|South Station
|
|10
|
|2,691
|-
|Kingston Line
|South Station
|<br /> (indefinitely closed)
|11 (1 closed)
| – Kingston<br /> – Plymouth
|4,171
|-
|Fall River/New Bedford Line
|South Station
|<br />
|15
| – Fall River<br /> – New Bedford
|5,261
|-
|Fairmount Line
|South Station
|
|9
|
|2,843
|-
|Providence/Stoughton Line
|South Station
|<br />
|18
| – Wickford Junction<br /> – Stoughton
|17,648
|-
|Franklin/Foxboro Line
|South Station
|<br />
|18