1st most populous of 44
With 535,799 residents in 2024, Ada County ranks 1st by population among Idaho's 44 counties and is home to 26.8% of the state's residents.
Ada County is home to 535,799 people (2024 estimate) on 1,052 square miles of land. This page brings together official U.S. Census Bureau population estimates since 2000, the components of change—births, deaths and migration—American Community Survey indicators on income, housing, poverty and education, BEA economic accounts and BLS unemployment.
Key indicators
Population
535,799
July 1, 2024 estimate
2020 Census base
494,969
April 1, 2020
Change since 2020
+8.2%
2020–2024
Land area
1,052 mi²
2,725 km²
Population density
509.3 /mi²
2024 estimate ÷ land area
Births
5,136
Year to July 1, 2024
Deaths
3,679
Year to July 1, 2024
Natural change
+1,457
Births minus deaths, 2024
Net migration
+7,592
Domestic + international, 2024
Per capita personal income
$76,921
BEA, 2024
Gross domestic product
$45.5 billion
BEA, current dollars, 2024
Median household income
$91,502
ACS 2020–2024 5-year
Poverty rate
8.3%
ACS 2020–2024 5-year
Bachelor’s degree or higher
44.6%
Age 25+, ACS 2020–2024 5-year
Foreign-born residents
6.2%
ACS 2020–2024 5-year
Median home value
$512,300
ACS 2020–2024 5-year
Unemployment rate
3.2%
BLS annual average, 2024
Historical data
Pick an indicator to see its long-run evolution.
Population
2000–2024535,799▲ 77%
U.S. Census Bureau: intercensal estimates 2000–2009, Vintage 2020 (2010–2019) and Vintage 2024 (2020–2024), July 1.
Data summary
| Indicator | Value | Year and source |
|---|---|---|
| Population estimate | 535,799 | 2024 · U.S. Census Bureau |
| Population, 2010 Census | 392,365 | 2010 · U.S. Census Bureau |
| Population, 2000 | 303,328 | July 1, 2000 · Census intercensal |
| Change since 2000 | +76.6% | 2000–2024 · Census |
| International migration | +2,352 | 2024 · Census Vintage 2024 |
| Domestic migration | +5,240 | 2024 · Census Vintage 2024 |
| Birth rate | 9.6 per 1,000 | 2024 · calculated |
| Death rate | 6.9 per 1,000 | 2024 · calculated |
| Population rank in Idaho | 1st of 44 | 2024 · calculated |
| Per capita personal income | $76,921 | BEA, 2024 · official |
| Gross domestic product | $45.5 billion | BEA, current dollars, 2024 · official |
| Median household income | $91,502 | ACS 2020–2024 5-year · official |
| Poverty rate | 8.3% | ACS 2020–2024 5-year · official |
| Bachelor’s degree or higher | 44.6% | Age 25+, ACS 2020–2024 5-year · official |
| Foreign-born residents | 6.2% | ACS 2020–2024 5-year · official |
| Median home value | $512,300 | ACS 2020–2024 5-year · official |
| Median gross rent | $1,577/month | ACS 2020–2024 5-year · official |
| Median age | 38.4 years | ACS 2020–2024 5-year · official |
| Households | 202,543 | ACS 2020–2024 5-year · official |
| Owner-occupied homes | 70.8% | ACS 2020–2024 5-year · official |
Ada County in context
Comparable indicators for Ada County, Idaho and the United States.
| Indicator | County | Idaho | U.S. | Reference |
|---|---|---|---|---|
| Population change 2020–2024 | +8.2% | +8.8% | +2.6% | Census Vintage 2024 |
| Birth rate (per 1,000) | 9.6 | 11.4 | 10.6 | 2024 |
| Death rate (per 1,000) | 6.9 | 8.3 | 9.1 | 2024 |
| Net migration rate (per 1,000) | 14.2 | 12.1 | 8.2 | 2024 |
| Population density (/mi²) | 509.3 | 24.2 | 96.3 | 2024 |
| Per capita personal income | $76,921 | $62,323 | $73,204 | BEA, 2024 |
| Median household income | $91,502 | $77,800 | $80,734 | ACS 2020–2024 5-year |
| Poverty rate | 8.3% | 10.6% | 12.5% | ACS 2020–2024 5-year |
| Bachelor’s degree or higher | 44.6% | 31.8% | 35.7% | Age 25+, ACS 2020–2024 5-year |
| Foreign-born residents | 6.2% | 5.9% | 14.1% | ACS 2020–2024 5-year |
| Median home value | $512,300 | $418,600 | $332,700 | ACS 2020–2024 5-year |
| Median gross rent | $1,577/month | $1,238/month | $1,413/month | ACS 2020–2024 5-year |
| Median age | 38.4 years | 37.3 years | 38.9 years | ACS 2020–2024 5-year |
| Owner-occupied homes | 70.8% | 72.1% | 65.2% | ACS 2020–2024 5-year |
Cities & towns
2 cities · choose how to order them
Did you know? Ada County
A quarter century of change
Its population went from 303,328 in 2000 to 535,799 in 2024, a change of +76.6%, compared with +54.0% for Idaho as a whole.
Births and deaths
In the year to July 2024 the county recorded 5,136 births and 3,679 deaths, so births outnumbered deaths by 1,457.
Record population
Annual Census estimates since 2000 put the county's highest population in 2024, at 535,799.
1st in density
Ada County has about 509.3 residents per square mile of land, ranking 1st of 44 counties; Idaho averages 24.2.
Household income rank
With a median household income of $91,502 (ACS 2020–2024 5-year), the county ranks 3rd of 44 Idaho counties; the state median is $77,800.
Size of the economy
Its economy produced $45.5 billion of GDP in 2024 (BEA), 1st largest among 44 Idaho counties.
Latest economic growth
Real GDP grew 4.8% in 2024, adjusted for inflation (BEA, chained 2017 dollars).
Sources and methodology
- U.S. Census Bureau — County population totals and components, Vintage 2024
- U.S. Census Bureau — County estimates 2010–2020
- U.S. Census Bureau — Intercensal estimates 2000–2010
- U.S. Census Bureau — Gazetteer files (land area)
- U.S. Census Bureau — American Community Survey 2020–2024 5-year
- U.S. Bureau of Economic Analysis — Regional economic accounts
- U.S. Bureau of Labor Statistics — LAUS