Illinois State House District 31

State Legislative District Profile (Lower Chamber)

Overview

District ID
il-hd-031
State
Illinois
Chamber
Lower chamber
District Code
031
Land Area
16 sq mi
Water Area
0.01 sq mi

Boundary

Boundary of Illinois State House District 31

Boundary as GeoJSON

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

Counties

CountyOverlapShare of district landShare of county land
Cook County15.95 sq mi100.0%1.7%

Showing all 1 county

Places

PlaceOverlapShare of district landShare of place land
Chicago city6.27 sq mi39.3%2.8%
Oak Lawn village2.55 sq mi16.0%29.8%
Hickory Hills city2.00 sq mi12.5%70.4%
Justice village1.97 sq mi12.3%69.3%
Palos Hills city0.89 sq mi5.6%21.0%
Bridgeview village0.79 sq mi4.9%19.1%
Chicago Ridge village0.68 sq mi4.3%30.0%
Hometown city0.48 sq mi3.0%100.0%

Showing all 8 places

Overlapping Congressional Districts

Congressional districtPopulation in bothShare of this district's populationShare of the congressional district's populationShare of this district's land
IL District 156,91052.4%7.6%36.1%
IL District 647,27743.5%6.3%59.4%
IL District 43,9203.6%0.5%3.4%
IL District 75310.5%0.1%1.2%

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

Voters

Registered Voters
75,630
Active Voters
69,663 (92.1%)

Party Registration

This state's voter file does not record party registration.

Turnout by Cycle

CycleGeneralDemocratic PrimaryRepublican Primary
2025–20263,445 (4.6%)<10 (—)0 (0.0%)
2023–202440,088 (53.0%)11,640 (15.4%)1,692 (2.2%)
2021–202226,752 (35.4%)10,661 (14.1%)2,245 (3.0%)
2019–202042,191 (55.8%)18,175 (24.0%)1,043 (1.4%)
2017–201830,817 (40.7%)15,373 (20.3%)1,412 (1.9%)
2015–201637,082 (49.0%)22,293 (29.5%)3,001 (4.0%)
2013–201423,445 (31.0%)5,697 (7.5%)1,505 (2.0%)
2011–201230,739 (40.6%)7,826 (10.3%)1,564 (2.1%)

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 12/15/2025. These are registered voters, separate from the Census population figures. Counts under 10 are suppressed and shown as "<10".

Demographics

Total Population
103,648 (± 3,449)
Median Age
39.4
Median Household Income
$60,483 (± $3,527)
High School Graduate or Higher (age 25+)
87.8%
Bachelor's Degree or Higher (age 25+)
22.9%

Population by Age

GroupPeopleShare
Under 1824,09323.2%
18 to 6461,64359.5%
65 and over17,91217.3%

Population by Race and Hispanic Origin

GroupPeopleShare
Hispanic or Latino (any race)13,29912.8%
White, not Hispanic33,17032.0%
Black, not Hispanic52,75150.9%
Asian, not Hispanic2,1872.1%
American Indian / Alaska Native, not Hispanic170.0%
Native Hawaiian / Pacific Islander, not Hispanic230.0%
Some other race, not Hispanic1540.1%
Two or more races, not Hispanic2,0472.0%

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
98,174
Citizen Voting Age Population (CVAP)
74,136

Citizen Population by Race/Ethnicity

GroupCitizensShare
Non-Hispanic87,01488.6%
Hispanic11,16111.4%
White30,88331.5%
Black52,79053.8%
Asian1,8631.9%
American Indian / Alaska Native260.0%
Native Hawaiian / Pacific Islander190.0%
Two or More Races2160.2%

Citizen Voting Age Population by Race/Ethnicity

GroupCVAPShare
Non-Hispanic67,18190.6%
Hispanic6,9549.4%
White24,12132.5%
Black41,20855.6%
Asian1,4752.0%
American Indian / Alaska Native3860.5%
Native Hawaiian / Pacific Islander250.0%
Two or More Races2170.3%

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