Massachusetts 9th Suffolk District

State Legislative District Profile (Lower Chamber)

Overview

District ID
ma-hd-131
State
Massachusetts
Chamber
Lower chamber
District Code
131
Land Area
1.97 sq mi
Water Area
0.01 sq mi

Boundary

Boundary of Massachusetts 9th Suffolk District

Boundary as GeoJSON

Source: U.S. Census Bureau TIGER/Line state legislative district boundaries.

Counties

CountyOverlapShare of district landShare of county land
Suffolk County1.97 sq mi100.0%3.4%

Showing all 1 county

Places

PlaceOverlapShare of district landShare of place land
Boston city1.97 sq mi100.0%4.1%

Showing all 1 place

Overlapping Congressional Districts

Congressional districtPopulation in bothShare of this district's populationShare of the congressional district's populationShare of this district's land
MA District 737,87390.6%4.8%79.5%
MA District 83,9479.4%0.5%20.5%

Source: U.S. Census Bureau 2020 blocks and 2025 block equivalency files (119th Congress, 2024 state legislative plans).

Voters

Registered Voters
29,864
Active Voters
26,897 (90.1%)

Party Registration

PartyVotersShare
Democratic10,88936.5%
Republican<10—
Unaffiliated00.0%
Other parties17,87459.9%
No party recorded<10—

Turnout by Cycle

CycleGeneralDemocratic PrimaryRepublican Primary
2025–20267,855 (26.3%)0 (0.0%)0 (0.0%)
2023–202417,475 (58.5%)5,022 (16.8%)920 (3.1%)
2021–202212,841 (43.0%)4,645 (15.6%)195 (0.7%)
2019–202016,101 (53.9%)9,905 (33.2%)485 (1.6%)
2017–201811,446 (38.3%)4,626 (15.5%)256 (0.9%)
2015–201612,285 (41.1%)5,650 (18.9%)828 (2.8%)
2013–20147,692 (25.8%)2,339 (7.8%)152 (0.5%)
2011–20129,688 (32.4%)1,567 (5.2%)388 (1.3%)

Turnout counts today's registered voters with a counted ballot in the cycle's elections (the odd and even year), as a share of today's registered voters. Voters who have since left the rolls are not counted.

Browse the voter list for this district (premium access; sign-in required)

Source: Civitech voter file snapshot as of 12/07/2025. These are registered voters, separate from the Census population figures. Counts under 10 are suppressed and shown as "<10".

Demographics

Total Population
42,037 (± 1,881)
Median Age
37.4
Median Household Income
$84,987 (± $9,736)
High School Graduate or Higher (age 25+)
88.9%
Bachelor's Degree or Higher (age 25+)
59.9%

Population by Age

GroupPeopleShare
Under 185,95714.2%
18 to 6429,65570.5%
65 and over6,42515.3%

Population by Race and Hispanic Origin

GroupPeopleShare
Hispanic or Latino (any race)6,85516.3%
White, not Hispanic19,75047.0%
Black, not Hispanic7,33917.5%
Asian, not Hispanic5,31212.6%
American Indian / Alaska Native, not Hispanic1510.4%
Native Hawaiian / Pacific Islander, not Hispanic360.1%
Some other race, not Hispanic4001.0%
Two or more races, not Hispanic2,1945.2%

Source: U.S. Census Bureau, American Community Survey 2020-2024 ACS 5-year estimates (tables B01001, B01002, B01003, B03002, B15003, B19013) for this state legislative district. Estimates are survey-based; ± figures are 90% margins of error.

Citizen Voting Age Population

Total Citizen Population
37,440
Citizen Voting Age Population (CVAP)
31,646

Citizen Population by Race/Ethnicity

GroupCitizensShare
Non-Hispanic31,94885.3%
Hispanic5,48614.7%
White19,64352.5%
Black7,36619.7%
Asian3,77910.1%
American Indian / Alaska Native1860.5%
Native Hawaiian / Pacific Islander360.1%
Two or More Races1420.4%

Citizen Voting Age Population by Race/Ethnicity

GroupCVAPShare
Non-Hispanic27,25286.1%
Hispanic4,39313.9%
White17,40155.0%
Black5,94718.8%
Asian3,58011.3%
American Indian / Alaska Native3101.0%
Native Hawaiian / Pacific Islander360.1%
Two or More Races1390.4%

Source: Redistricting Data Hub / U.S. Census Bureau CVAP Special Tabulation (2020-2024 ACS 5-year).