Ada County, Idaho Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 1st-largest in Idaho
The population of Ada County, Idaho is 508,052 as of the 2023 American Community Survey, making it the 1st-largest county in Idaho. The median household income is $88,907, the median home value is $476,000, and the median age is 38.3.
The population of Ada County has grown 36.2% since 2010 (393,369 → 535,799), a +2.23% annualized rate.
508,052
Population
+2.23%
Annual growth
483
People / sq mi
$88,907
Median Income
$476,000
Median Home Value
Ada County covers 1,052 sq mi of land at 482.8 people per square mile.
About Ada County, ID
Ada County is a county in Idaho with a population of 508,052. It ranks #1 among counties in Idaho by population. The median age is 38.3, in line with the national median. The population is 50.4% male and 49.6% female.
The median household income in Ada County is $88,907, above the US median of $74,580. 5.5% of residents live below the federal poverty level. Home values sit at a median of $476,000, with monthly rent averaging $1,465. The homeownership rate of 71.4% is higher than the national rate of 64.8%.
Educational attainment in Ada County reflects 43.9% of adults 25 and older holding a bachelor's degree or higher, above the national average of 34.3%. Roughly 16.8% of workers primarily work from home, similar to the national work-from-home rate of 14.2%. The average commute is 21.2 minutes each way.
Ada County Population History (2010-2024)
The county of Ada County had a population of 393,369 in 2010 and 535,799 in 2024, a 36.2% growth over 14 years. The peak was 535,799 in 2024. Average annual growth rate: 2.23%.
535,799
Population (2024)
393,369
Population (2010)
535,799
Peak (2024)
2.23%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 393,369 |
| 2011 | 401,352 |
| 2012 | 409,032 |
| 2013 | 416,180 |
| 2014 | 425,774 |
| 2015 | 433,254 |
| 2016 | 444,929 |
| 2017 | 456,994 |
| 2018 | 469,161 |
| 2019 | 481,880 |
| 2020 | 498,301 |
| 2021 | 513,098 |
| 2022 | 520,788 |
| 2023 | 526,690 |
| 2024 | 535,799 |
Race & Ethnicity
| White | 84.8% |
| Black or African American | 1.3% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 2.2% |
| Two or More Races | 0.0% |
Age & Sex
38.3
Median Age
49.6%
Female
50.4%
Male
15.8%
Age 65+
Age Distribution
Children (under 15): 18.2% · Seniors (65+): 15.8%
Income & Poverty
| Median household income | $88,907+$14,271 vs state |
| Mean household income | $121,034 |
| Per-capita income | $47,768 |
| Poverty rate | 5.5%-1.5% vs state |
| Unemployment rate | 2.1% |
| Employment-to-population | 64.1% |
Top Industries by Employment
The largest employment sector in Ada County is professional & business services, accounting for 22.7% of workers.
How residents commute
0.4%
Drive alone
2.3%
Carpool
70.6%
Public transit
16.8%
Work from home
21.2 min
Avg commute
Housing
$476,000+$100,000 vs state
Median home value
$1,465
Median rent
71.4%
Homeownership rate
205,068
Total housing units
95.9%
Occupied
4.1%
Vacant
28.6%
Renter-occupied
Social & access
93.3%
With health insurance
97.8%
With broadband internet
53.5%
Foreign-born
8.0%
Veterans (18+)
11.2%
With a disability
91.0%
Speak language other than English at home
Education
95.1%
High School+
43.9%
Bachelor's+
Largest cities in Idaho
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County rankings
Common questions about Ada County, ID
Frequently Asked Questions
Ada County, Idaho has a population of 508,052 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 1st-largest county in Idaho. Population density is 483 people per square mile.
The population of Ada County has grown 36.2% since 2010 (393,369 → 535,799), a +2.23% annualized rate.
The median household income in Ada County, Idaho is $88,907, with mean (average) household income of $121,034 and per-capita income of $47,768. 5.5% of residents live below the federal poverty level.
In Ada County, the largest racial and ethnic groups are White (84.8%), Hispanic or Latino (2.2%), Black or African American (1.3%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Ada County, Idaho is 38.3 years. Residents are 49.6% female and 50.4% male.
The median home value in Ada County is $476,000 and median monthly rent is $1,465. 71.4% of occupied housing units are owner-occupied. The county has 205,068 total housing units, 4.1% of which are vacant.
The largest employment sector in Ada County, Idaho is professional, scientific, and management services, employing 22.7% of workers. The unemployment rate is 2.1%.
Boise City is among the largest cities associated with Ada County, Idaho, with a population of 235,701.
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Statewide data for Idaho
Population, race, income, age, and trends across Idaho
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.