Data / Rankings / Population / Counties in Washington

Counties in Washington by population

King County had the highest population of 39 counties in 2020, at 2.27 million. Garfield County had the lowest, at 2,296. The median was 66,041 and the figure for Washington was 7.73 million. Source: the U.S. Census Bureau.

Highest2,274,304King County
Lowest2,296Garfield County
Median66,04139 counties
Washington7,726,812History

All counties, 2020

CSVChart (SVG)

King CountyKing County: 2,274,304 persons2,274,304Pierce CountyPierce County: 923,609 persons923,609Snohomish CountySnohomish County: 829,901 persons829,901Spokane CountySpokane County: 541,144 persons541,144Clark CountyClark County: 505,325 persons505,325Thurston CountyThurston County: 296,013 persons296,013Kitsap CountyKitsap County: 275,811 persons275,811Yakima CountyYakima County: 256,716 persons256,716Whatcom CountyWhatcom County: 227,452 persons227,452Benton CountyBenton County: 207,408 persons207,408Skagit CountySkagit County: 129,885 persons129,885Cowlitz CountyCowlitz County: 111,014 persons111,014Grant CountyGrant County: 99,446 persons99,446Franklin CountyFranklin County: 97,137 persons97,137Island CountyIsland County: 87,001 persons87,001Lewis CountyLewis County: 82,551 persons82,551Chelan CountyChelan County: 79,302 persons79,302Clallam CountyClallam County: 77,356 persons77,356Grays Harbor CountyGrays Harbor County: 75,866 persons75,866Mason CountyMason County: 66,041 persons66,041Walla Walla CountyWalla Walla County: 62,620 persons62,620Whitman CountyWhitman County: 47,816 persons47,816Kittitas CountyKittitas County: 46,823 persons46,823Stevens CountyStevens County: 46,585 persons46,585Douglas CountyDouglas County: 43,033 persons43,033Okanogan CountyOkanogan County: 42,143 persons42,143Jefferson CountyJefferson County: 33,064 persons33,064Pacific CountyPacific County: 23,503 persons23,503Klickitat CountyKlickitat County: 22,817 persons22,817Asotin CountyAsotin County: 22,327 persons22,327Adams CountyAdams County: 20,610 persons20,610San Juan CountySan Juan County: 17,825 persons17,825Pend Oreille CountyPend Oreille County: 13,505 persons13,505Skamania CountySkamania County: 12,038 persons12,038Lincoln CountyLincoln County: 10,926 persons10,926Ferry CountyFerry County: 7,199 persons7,199Wahkiakum CountyWahkiakum County: 4,446 persons4,446Columbia CountyColumbia County: 3,954 persons3,954Garfield CountyGarfield County: 2,296 persons2,296
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2020
persons
1King County2,274,304
2Pierce County923,609
3Snohomish County829,901
4Spokane County541,144
5Clark County505,325
6Thurston County296,013
7Kitsap County275,811
8Yakima County256,716
9Whatcom County227,452
10Benton County207,408
11Skagit County129,885
12Cowlitz County111,014
13Grant County99,446
14Franklin County97,137
15Island County87,001
16Lewis County82,551
17Chelan County79,302
18Clallam County77,356
19Grays Harbor County75,866
20Mason County66,041
21Walla Walla County62,620
22Whitman County47,816
23Kittitas County46,823
24Stevens County46,585
25Douglas County43,033
26Okanogan County42,143
27Jefferson County33,064
28Pacific County23,503
29Klickitat County22,817
30Asotin County22,327
31Adams County20,610
32San Juan County17,825
33Pend Oreille County13,505
34Skamania County12,038
35Lincoln County10,926
36Ferry County7,199
37Wahkiakum County4,446
38Columbia County3,954
39Garfield County2,296

Other periods

About this ranking

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (Padrón). United States: Census Bureau population estimates for 1 July. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

For Denmark, Statistics Denmark counts the registered resident population on 1 January. Greenland and the Faroe Islands are excluded. The annual series selects the first-quarter reference date from FOLK1A. The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-08.

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Questions

Which county has the highest population?

King County, with 2.27 million in 2020, according to the U.S. Census Bureau.

Which county has the lowest population?

Garfield County, with 2,296 in 2020.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). Retrieved 2026-10-08.

Population: other rankings

Counties in Washington: more rankings