Overview
- District ID
- il-sd-021
- State
- Illinois
- Chamber
- Upper chamber (state senate)
- District Code
- 021
- Land Area
- 62.4 sq mi
- Water Area
- 1.06 sq mi
Boundary
Boundary as GeoJSON
Source: U.S. Census Bureau TIGER/Line state legislative district boundaries.
Counties
| County | Overlap | Share of district land | Share of county land |
|---|
| DuPage County | 52.22 sq mi | 83.7% | 15.9% |
| Will County | 10.18 sq mi | 16.3% | 1.2% |
Showing all 2 counties
Places
Showing all 12 places
Overlapping Congressional Districts
| Congressional district | Population in both | Share of this district's population | Share of the congressional district's population | Share of this district's land |
|---|
| IL District 6 | 98,488 | 45.3% | 13.1% | 44.7% |
| IL District 11 | 78,950 | 36.3% | 10.5% | 38.2% |
| IL District 14 | 29,084 | 13.4% | 3.9% | 13.4% |
| IL District 3 | 10,734 | 4.9% | 1.4% | 3.7% |
Source: U.S. Census Bureau 2020 blocks and 2025 block equivalency files (119th Congress, 2024 state legislative plans).
Voters
- Registered Voters
- 167,627
- Active Voters
- 151,984 (90.7%)
Party Registration
This state's voter file does not record party registration.
Turnout by Cycle
| Cycle | General | Democratic Primary | Republican Primary |
|---|
| 2025–2026 | 38,354 (22.9%) | 1,642 (1.0%) | <10 (—) |
| 2023–2024 | 115,819 (69.1%) | 20,392 (12.2%) | 12,747 (7.6%) |
| 2021–2022 | 87,558 (52.2%) | 19,517 (11.6%) | 15,606 (9.3%) |
| 2019–2020 | 111,613 (66.6%) | 31,080 (18.5%) | 10,317 (6.2%) |
| 2017–2018 | 85,243 (50.9%) | 20,294 (12.1%) | 14,786 (8.8%) |
| 2015–2016 | 87,574 (52.2%) | 25,291 (15.1%) | 27,004 (16.1%) |
| 2013–2014 | 55,797 (33.3%) | 3,160 (1.9%) | 16,930 (10.1%) |
| 2011–2012 | 68,263 (40.7%) | 4,800 (2.9%) | 16,743 (10.0%) |
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
- 217,202 (± 3,574)
- Median Age
- 39.2
- Median Household Income
- $125,645 (± $4,168)
- High School Graduate or Higher (age 25+)
- 96.3%
- Bachelor's Degree or Higher (age 25+)
- 62.6%
Population by Age
| Group | People | Share |
|---|
| Under 18 | 50,906 | 23.4% |
| 18 to 64 | 130,757 | 60.2% |
| 65 and over | 35,539 | 16.4% |
Population by Race and Hispanic Origin
| Group | People | Share |
|---|
| Hispanic or Latino (any race) | 23,476 | 10.8% |
| White, not Hispanic | 144,464 | 66.5% |
| Black, not Hispanic | 9,979 | 4.6% |
| Asian, not Hispanic | 29,742 | 13.7% |
| American Indian / Alaska Native, not Hispanic | 158 | 0.1% |
| Native Hawaiian / Pacific Islander, not Hispanic | 98 | 0.0% |
| Some other race, not Hispanic | 971 | 0.4% |
| Two or more races, not Hispanic | 8,314 | 3.8% |
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
- 202,026
- Citizen Voting Age Population (CVAP)
- 152,910
Citizen Population by Race/Ethnicity
| Group | Citizens | Share |
|---|
| Non-Hispanic | 182,666 | 90.4% |
| Hispanic | 19,361 | 9.6% |
| White | 143,586 | 71.1% |
| Black | 9,959 | 4.9% |
| Asian | 22,790 | 11.3% |
| American Indian / Alaska Native | 158 | 0.1% |
| Native Hawaiian / Pacific Islander | 99 | 0.0% |
| Two or More Races | 546 | 0.3% |
Citizen Voting Age Population by Race/Ethnicity
| Group | CVAP | Share |
|---|
| Non-Hispanic | 140,878 | 92.1% |
| Hispanic | 12,031 | 7.9% |
| White | 113,400 | 74.2% |
| Black | 8,899 | 5.8% |
| Asian | 17,644 | 11.5% |
| American Indian / Alaska Native | 543 | 0.4% |
| Native Hawaiian / Pacific Islander | 42 | 0.0% |
| Two or More Races | 367 | 0.2% |
Source: Redistricting Data Hub / U.S. Census Bureau CVAP Special Tabulation (2020-2024 ACS 5-year).
