Total Population in Ada County, ID
ACS 2024 5-Year Estimates
518,935
Rank #140/3,222 · #1 in ID
96th
Ada 518,935
ID 1,934,262 -73.2%
US 330M
Total Population Trend
Rankings →Percentile Rank Over Time
Year-over-Year Population Change
National Distribution
How Ada County's total population of 518,935 compares to all 3,222 U.S. counties. Values range from 33 to 9,808,667.
Distribution of Total Population Across All Counties
Ranking Context
Counties ranked closest to Ada County for total population.
Nearby Rankings
Full ranking →| #137 | Sedgwick County, KS | 528,226 |
| #138 | Camden County, NJ | 527,257 |
| #139 | Passaic County, NJ | 521,012 |
| #140 | Ada County, ID | 518,935 |
| #141 | Kane County, IL | 517,255 |
| #142 | Clark County, WA | 516,959 |
| #143 | Morris County, NJ | 514,528 |
About Total Population
Ada County, Idaho has a total population of 518,935, ranking #140 of 3,222 counties nationwide — 99.8% below the national value of 330M. Within Idaho, it ranks #1 of 44. This places it in the 96th percentile nationally.
Total population count from the American Community Survey. Source: U.S. Census Bureau, American Community Survey 2024 5-Year Estimates. All values are estimates derived from survey samples and are subject to margin of error. For more information, see our methodology.