# Counties in Washington by population aged 18 to 64, 2025

All 39 values come from U.S. Census Bureau for 2025, so the places are comparable.

- Indicator id: `population_18_64_share`
- Unit: %
- Definition: Residents aged 18 to 64 as a percentage of total population on 1 July. United States: Census Bureau county population estimates by age; states and the nation are sums of their counties.
- Source: U.S. Census Bureau, Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties (https://www.census.gov/programs-surveys/popest/data/data-sets.html)
- Retrieved: 2026-10-12
- Citation: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.
- Web page: https://invokely.ai/rankings/population-18-64/washington-counties

| Rank | Place | % |
|---:|---|---:|
| 1 | Whitman County | 70.9 |
| 2 | King County | 66.2 |
| 3 | Kittitas County | 62.3 |
| 4 | Snohomish County | 62.1 |
| 5 | Whatcom County | 61.4 |
| 6 | Pierce County | 61.3 |
| 7 | Clark County | 60.4 |
| 8 | Spokane County | 59.9 |
| 9 | Franklin County | 59.9 |
| 10 | Thurston County | 59.4 |
| 11 | Kitsap County | 59.4 |
| 12 | Walla Walla County | 58.3 |
| 13 | Benton County | 58 |
| 14 | Douglas County | 57.7 |
| 15 | Grant County | 57.4 |
| 16 | Yakima County | 57.3 |
| 17 | Skamania County | 56.9 |
| 18 | Cowlitz County | 56.7 |
| 19 | Chelan County | 55.6 |
| 20 | Grays Harbor County | 55.5 |
| 21 | Lewis County | 55.4 |
| 22 | Klickitat County | 55.4 |
| 23 | Mason County | 55.3 |
| 24 | Adams County | 55.1 |
| 25 | Skagit County | 54.9 |
| 26 | Okanogan County | 54.5 |
| 27 | Island County | 53.2 |
| 28 | Asotin County | 53 |
| 29 | Stevens County | 51.7 |
| 30 | Columbia County | 51.6 |
| 31 | Pend Oreille County | 51 |
| 32 | Ferry County | 50.9 |
| 33 | Lincoln County | 50.6 |
| 34 | Pacific County | 50.5 |
| 35 | Garfield County | 50.1 |
| 36 | Wahkiakum County | 49.9 |
| 37 | Clallam County | 49.5 |
| 38 | San Juan County | 48.8 |
| 39 | Jefferson County | 45.1 |