Ada County, Idaho
Ada County, Idaho, has 546,141 residents (July 2025 estimate). Its county seat is Boise. It uses Mountain Time and covers 1,052 sq mi (2,725 km²) of land.
- Resident population, July 2025
- 546,141
- Land area
- 1,052 sq mi (2,725 km²)
- County seat or government
- Boise
- Time zone
- Mountain TimeUTC-07:00 in January; UTC-06:00 in July
- Median household income
- $91,502 ± $1,355
- Median home value
- $512,300 ± $8,186
- Median rent, with utilities
- $1,577 ± $32
- Homes lived in by their owners
- 70.8% ± 0.7 points
- County type
- County
- Metro or micro area
- Boise City, ID metro areaCentral county
- Water area
- 8.51 sq mi (22 km²)
- State
- Idaho
- County code (FIPS)
- 16001
- Coordinates (central point)
- 43.451476, -116.244376
These coordinates mark a central point for the area, not a street address. Income, home value, rent and homes lived in by their owners: U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, ± margin at 90% confidence; checked on October 13, 2026.
Time zones in Ada County
| Time zone | Local time and UTC offset | Next clock change |
|---|---|---|
| Mountain TimeAmerica/Boise | UTC-07:00 in January; UTC-06:00 in July. Enable JavaScript for the live clock. | Enable JavaScript for upcoming changes. |
Near a time-zone line, check where you are with the time-zone finder. Your phone’s setting can differ.
ZIP Code areas, largest first
- 8364676,023 people
- 8364262,279 people
- 8370958,928 people
- 8368743,135 people
- 8370442,719 people
- 8363436,286 people
- 8370635,524 people
- 8361635,413 people
- 8371331,549 people
- 8371427,564 people
- 8370526,830 people
- 8370224,163 people
All 20
20 ZIP Code areas overlap Ada County. People counts are 2020–2024 estimates for each whole ZIP area. Mailing ZIPs can differ; check an address with USPS ZIP Code Lookup.
Official county information
We don’t have a website for this county yet. The US government’s local-office directory ↗ lists its offices. A geographic lookup cannot determine eligibility, tax liability or a court obligation.
School districts in Ada County, largest first
- Meridian Joint School District 2271,490 people
- Boise City Independent School District 1212,323 people
- Kuna Joint School District 338,009 people
- Melba Joint School District 1363,354 people
Districts with land in the county; a district can cross county lines. People counts are American Community Survey 2020–2024 5-year estimates. A district boundary doesn’t decide which school a student attends.
Cities, towns and communities, largest first
These areas overlap the mapped boundary; an overlap does not mean that every address belongs to both.
- Boise City, Idaho (city)237,242 people
- Meridian, Idaho (city)130,138 people
- Eagle, Idaho (city)32,855 people
- Kuna, Idaho (city)27,158 people
- Star, Idaho (city)14,745 people
- Garden City, Idaho (city)12,654 people
- Hidden Springs, Idaho (CDP)3,378 people
- Avimor, Idaho (CDP)586 people
Bordering areas, nearest first
Distances are straight lines between map points.
- Canyon County, Idaho26 mi northwest
- Elmore County, Idaho39 mi east
- Gem County, Idaho43 mi north
- Boise County, Idaho45 mi northeast
- Owyhee County, Idaho61 mi south
Before using this answer on a form
Use a precise point for address-level questions. A device accuracy circle can cross a boundary; confirm tax, voting or jury details with the responsible office.
Find the county where you are now, check its ZIP area, or check the time zone where you are.
Areas that only touch the edge
These areas meet the boundary only along a sliver. Most addresses here are not in them; for an address near the line, check with the county.