Idaho State House District 21

State Legislative District Profile (Lower Chamber)

Overview

District ID
id-hd-021
State
Idaho
Chamber
Lower chamber
District Code
021
Land Area
20.9 sq mi
Water Area
0.04 sq mi

Boundary

Boundary of Idaho State House District 21

Boundary as GeoJSON

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

Counties

CountyOverlapShare of district landShare of county land
Ada County20.85 sq mi100.0%2.0%

Showing all 1 county

Places

PlaceOverlapShare of district landShare of place land
Meridian city15.62 sq mi74.9%42.1%
Boise City city0.32 sq mi1.5%0.4%

Showing all 2 places

Overlapping Congressional Districts

Congressional districtPopulation in bothShare of this district's populationShare of the congressional district's populationShare of this district's land
ID District 150,23494.7%5.5%92.8%
ID District 22,8325.3%0.3%7.2%

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

Voters

Registered Voters
29,986
Active Voters
29,986 (100.0%)

Party Registration

PartyVotersShare
Democratic3,96213.2%
Republican17,21957.4%
Unaffiliated8,35627.9%
Other parties4491.5%
No party recorded00.0%

Turnout by Cycle

CycleGeneralDemocratic PrimaryRepublican Primary
2025–20266,387 (21.3%)0 (0.0%)0 (0.0%)
2023–202426,912 (89.7%)0 (0.0%)0 (0.0%)
2021–202217,025 (56.8%)0 (0.0%)0 (0.0%)
2019–202021,200 (70.7%)2,808 (9.4%)5,825 (19.4%)
2017–201814,637 (48.8%)917 (3.1%)4,518 (15.1%)
2015–201615,143 (50.5%)347 (1.2%)5,184 (17.3%)
2013–20149,377 (31.3%)258 (0.9%)2,682 (8.9%)
2011–201211,874 (39.6%)0 (0.0%)0 (0.0%)

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 01/12/2026. These are registered voters, separate from the Census population figures. Counts under 10 are suppressed and shown as "<10".

Demographics

Total Population
58,054 (± 2,345)
Median Age
38.9
Median Household Income
$88,486 (± $5,842)
High School Graduate or Higher (age 25+)
93.9%
Bachelor's Degree or Higher (age 25+)
38.0%

Population by Age

GroupPeopleShare
Under 1812,89522.2%
18 to 6435,19960.6%
65 and over9,96017.2%

Population by Race and Hispanic Origin

GroupPeopleShare
Hispanic or Latino (any race)6,95212.0%
White, not Hispanic47,22981.4%
Black, not Hispanic7261.3%
Asian, not Hispanic1,0231.8%
American Indian / Alaska Native, not Hispanic1110.2%
Native Hawaiian / Pacific Islander, not Hispanic1150.2%
Some other race, not Hispanic1200.2%
Two or more races, not Hispanic1,7783.1%

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
56,347
Citizen Voting Age Population (CVAP)
43,610

Citizen Population by Race/Ethnicity

GroupCitizensShare
Non-Hispanic50,50189.6%
Hispanic5,84410.4%
White47,35084.0%
Black7371.3%
Asian7331.3%
American Indian / Alaska Native1090.2%
Native Hawaiian / Pacific Islander1000.2%
Two or More Races2360.4%

Citizen Voting Age Population by Race/Ethnicity

GroupCVAPShare
Non-Hispanic39,87591.4%
Hispanic3,7358.6%
White37,46685.9%
Black6971.6%
Asian1,1482.6%
American Indian / Alaska Native3160.7%
Native Hawaiian / Pacific Islander870.2%
Two or More Races1580.4%

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