The New Bedford Subdivision is a railroad line in the U.S. state of Massachusetts owned by the Massachusetts Bay Transit Authority, with freight operations handled by the Massachusetts Coastal Railroad. The line runs from the end of the CSX Middleboro Subdivision near Weir Village (in Taunton) south to New Bedford along a former New York, New Haven and Hartford Railroad line. It junctions the Fall River Subdivision at Myricks (in Berkley).
The New Bedford and Taunton Railroad completed the line from Taunton south to New Bedford in 1840. It became part of the NYNH&H until 1959 Penn Central took over in 1968 Conrail took over in 1976. Through leases, mergers, and takeovers, and was assigned to CSX in 1999 after the breakup of Conrail.
In May 2010, the New Bedford and Fall River Subdivisions were sold to the State of Massachusetts for the South Coast Rail project. CSX also transferred all freight operations to the Massachusetts Coastal Railroad.