Massachusetts's 4th congressional district is located mostly in southern Massachusetts. It is represented by Democrat Joe Kennedy III. The district covers much of the area included in the before the 1982 redistricting. In prior years, the district stretched from Brookline to Fitchburg. The shape of the district underwent some changes effective from the elections of 2012, after Massachusetts congressional redistricting to reflect the 2010 census. Most of Plymouth County and the South Coast are included in the new 9th district. The new 4th district has expanded westward to include towns along the Rhode Island border that had been in the old 3rd district. For a very brief time it represented part of the District of Maine.
In Bristol County: In Middlesex County: In Norfolk County: In Plymouth County: In Worcester County:
Cities and towns in the district prior to 2013
1840s
"The towns of Acton, Ashby, Bedford, Boxborough, Burlington, Cambridge, Charlestown, Concord, Framingham, Hopkinton, Lexington, Lincoln, Marlborough, Pepperell, Shirley, Somerville, Stow, Sudbury, Townsend, Waltham, Watertown, Wayland, West Cambridge, Weston and Woburn, in the County of Middlesex, and the towns of Berlin, Bolton, Boylston, Fitchburg, Harvard, Lancaster, Leominster, Lunenburg, Northboro', Shrewsbury, Southborough, Sterling, and Westborough, in the County of Worcester."
1850s
"The city of Roxbury, and the town of Brookline, in the county of Norfolk; and the wards numbered seven, eight, nine, ten, eleven, and twelve, in the city of Boston, in the county of Suffolk."
1860s
Boston, Cambridge, Chelsea.
1870s
Boston, Chelsea, Revere, and Winthrop.
1880s–1900s
1910s
"Worcester County: City of Worcester; towns of Auburn, Blackstone Douglas, Grafton, Hopedale, Mendon, Milford, Millbury, Northbridge, Shrewsbury, Sutton, Upton, Uxbridge, and Westboro. Middlesex County: Town of Hopkinton."
1920s–1930s
1940s
In Middlesex County: Ashland, Framingham, Hopkinton, Sudbury, Waltham, Wayland, Weston. In Worcester County: Auburn, Berlin, Boylston, Grafton, Holden, Northborough, Shrewsbury, Southborough, Sterling, Westborough, West Boylston, Worcester.
1950s–1960s
1970s
"Middlesex County: Cities of Newton and Waltham. Towns of Ayer, Framingham, Lincoln, Maynard, Shirley, Stow, Sudbury, Wayland, and Weston. Norfolk County: Town of Brookline. Worcester County: Cities of Fitchburg, Gardner, and Leominster. Towns of Bolton, Harvard, Lancaster, Lunenburg, and Westminster."
2003 to 2013
In Bristol County: In Middlesex County: In Norfolk County: In Plymouth County:
