Massachusetts's congressional districts
is currently divided into 9 congressional districts, each represented by a member of the United States House of Representatives. After the 2010 census, the number of Massachusetts's seats was decreased from 10 to 9 due to the State's low growth in population since the year 2000. This mandatory redistricting after the 2010 census eliminated Massachusetts's 10th congressional district, and also caused a major shift in how the state's congressional districts are currently drawn.
Current districts and representatives
List of members of the Massachusettsan United States House delegation, their terms, their district boundaries, and the districts' political rating according to the CPVI. The delegation has a total of 9 members, all of whom are members of the Democratic party.| District | Representative | Party | CPVI | Incumbency | District map |
| 1st | Richard Neal | Democratic | D+12 | January 3, 1989 – present | |
| 2nd | Jim McGovern | Democratic | D+9 | January 3, 1997 – present | |
| 3rd | Lori Trahan | Democratic | D+9 | January 3, 2019 – present | |
| 4th | Joe Kennedy III | Democratic | D+9 | January 3, 2013 – present | |
| 5th | Katherine Clark | Democratic | D+18 | December 12, 2013 – present | |
| 6th | Seth Moulton | Democratic | D+6 | January 3, 2015 – present | |
| 7th | Ayanna Pressley | Democratic | D+34 | January 3, 2019 – present | |
| 8th | Stephen Lynch | Democratic | D+10 | October 16, 2001 – present | |
| 9th | Bill Keating | Democratic | D+4 | January 3, 2011 – present |
Enumeration trends
After the 1890 Census and starting with the Fifty-third United States Congress in 1893, Massachusetts Congressional Districts were numbered west to east: with the in the west and the highest numbered district at Cape Cod.Before then, the district numeration was not as consistent; sometimes running east to west, other times going counter-clockwise around Boston.
History of apportionment
| Census Year | Resident Population | Number of Representatives | Constituents per Representative | Constituents per Representative |
| 1789 | No Census | 8 | N/A | N/A |
| 1790 | 378,787 | 14 | 27,056 | 30,000 |
| 1800 | 422,845 | 17 | 24,873 | 33,000 |
| 1810 | 472,040 | 20 | 23,602 | 35,000 |
| 1820 | 523,287 | 13 | 40,253 | 40,000 |
| 1830 | 610,408 | 12 | 50,867 | 47,700 |
| 1840 | 737,699 | 10 | 73,770 | 70,680 |
| 1850 | 994,514 | 11 | 90,410 | 93,425 |
| 1860 | 1,231,066 | 10 | 123,107 | 127,381 |
| 1870 | 1,457,351 | 11 | 132,486 | 131,425 |
| 1880 | 1,783,085 | 12 | 148,590 | 151,912 |
| 1890 | 2,238,947 | 13 | 172,227 | 173,901 |
| 1900 | 2,805,346 | 14 | 200,381 | 194,182 |
| 1910 | 3,366,416 | 16 | 210,401 | 212,407 |
| 1920 | 3,852,356 | 16 | N/A | N/A |
| 1930 | 4,249,614 | 15 | 283,307 | 280,675 |
| 1940 | 4,316,721 | 14 | 308,337 | 301,164 |
| 1950 | 4,690,514 | 14 | 335,037 | 344,587 |
| 1960 | 5,148,578 | 12 | 429,048 | 410,481 |
| 1970 | 5,689,170 | 12 | 477,223 | 469,088 |
| 1980 | 5,737,093 | 11 | 521,549 | 519,235 |
| 1990 | 6,016,425 | 10 | 602,905 | 572,466 |
| 2000 | 6,349,097 | 10 | 635,557 | 646,952 |
| 2010 | 6,547,629 | 9 | 728,849 | 710,767 |
Source: U.S. Census Bureau.
Historical and present district boundaries
Table of United States congressional district boundary maps in the State of Massachusetts, presented chronologically. All redistricting events that took place in Massachusetts between 1973 and 2013 are shown.| Year | Statewide map | Boston highlight |
| 1973–1982 | ||
| 1983–1992 | ||
| 1993–2002 | ||
| 2003–2013 | ||
| Since 2013 |
19th century
20th century
21st century