All counties in Washington
| County Name | Population | State | Rank |
|---|
| King County | 1,931,249 | Washington | 1 |
| Pierce County | 795,225 | Washington | 2 |
| Snohomish County | 713,335 | Washington | 3 |
| Spokane County | 471,221 | Washington | 4 |
| Clark County | 425,363 | Washington | 5 |
| Thurston County | 252,264 | Washington | 6 |
| Kitsap County | 251,133 | Washington | 7 |
| Yakima County | 243,231 | Washington | 8 |
| Whatcom County | 201,140 | Washington | 9 |
| Benton County | 175,177 | Washington | 10 |
| Skagit County | 116,901 | Washington | 11 |
| Cowlitz County | 102,410 | Washington | 12 |
| Grant County | 89,120 | Washington | 13 |
| Island County | 78,506 | Washington | 14 |
| Franklin County | 78,163 | Washington | 15 |
| Lewis County | 75,455 | Washington | 16 |
| Grays Harbor County | 72,797 | Washington | 17 |
| Chelan County | 72,453 | Washington | 18 |
| Clallam County | 71,404 | Washington | 19 |
| Mason County | 60,699 | Washington | 20 |
| Walla Walla County | 58,781 | Washington | 21 |
| Whitman County | 44,776 | Washington | 22 |
| Stevens County | 43,531 | Washington | 23 |
| Okanogan County | 41,120 | Washington | 24 |
| Kittitas County | 40,915 | Washington | 25 |
| Douglas County | 38,431 | Washington | 26 |
| Jefferson County | 29,872 | Washington | 27 |
| Asotin County | 21,623 | Washington | 28 |
| Pacific County | 20,920 | Washington | 29 |
| Klickitat County | 20,318 | Washington | 30 |
| Adams County | 18,728 | Washington | 31 |
| San Juan County | 15,769 | Washington | 32 |
| Pend Oreille County | 13,001 | Washington | 33 |
| Skamania County | 11,066 | Washington | 34 |
| Lincoln County | 10,570 | Washington | 35 |
| Ferry County | 7,551 | Washington | 36 |
| Columbia County | 4,078 | Washington | 37 |
| Wahkiakum County | 3,978 | Washington | 38 |
| Garfield County | 2,266 | Washington | 39 |