Counties in Washington by population

Name: Counties in Washington by population, 2021
Creator: U.S. Census Bureau
License: Public domain (US federal government work, citation requested)

King County had the highest population of 39 counties in 2021, at 2.25 million. Garfield County had the lowest, at 2,347. The median was 67,271 and the figure for Washington was 7.74 million. Source: the U.S. Census Bureau.

Highest2,253,549King County

Lowest2,347Garfield County

Median67,27139 counties

Washington7,744,316History

All counties, 2021

CSV Chart (SVG)

persons. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

Rank	Counties	2021 persons	Change on 2020
1	King County	2,253,549	-0.9%
2	Pierce County	927,786	+0.5%
3	Snohomish County	836,262	+0.8%
4	Spokane County	545,511	+0.8%
5	Clark County	512,654	+1.5%
6	Thurston County	298,313	+0.8%
7	Kitsap County	276,682	+0.3%
8	Yakima County	256,767	0%
9	Whatcom County	226,760	-0.3%
10	Benton County	210,612	+1.5%
11	Skagit County	131,013	+0.9%
12	Cowlitz County	111,703	+0.6%
13	Grant County	100,439	+1%
14	Franklin County	98,096	+1%
15	Island County	87,606	+0.7%
16	Lewis County	84,576	+2.5%
17	Chelan County	79,856	+0.7%
18	Clallam County	78,448	+1.4%
19	Grays Harbor County	76,889	+1.3%
20	Mason County	67,271	+1.9%
21	Walla Walla County	62,228	-0.6%
22	Stevens County	47,626	+2.2%
23	Kittitas County	45,653	-2.5%
24	Douglas County	43,850	+1.9%
25	Whitman County	43,257	-9.5%
26	Okanogan County	42,761	+1.5%
27	Jefferson County	33,558	+1.5%
28	Pacific County	24,028	+2.2%
29	Klickitat County	23,178	+1.6%
30	Asotin County	22,473	+0.7%
31	Adams County	20,644	+0.2%
32	San Juan County	18,629	+4.5%
33	Pend Oreille County	13,894	+2.9%
34	Skamania County	12,214	+1.5%
35	Lincoln County	11,283	+3.3%
36	Ferry County	7,292	+1.3%
37	Wahkiakum County	4,587	+3.2%
38	Columbia County	4,021	+1.7%
39	Garfield County	2,347	+2.2%

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 2.25 million in 2021, according to the U.S. Census Bureau.

Which county has the lowest population?

Garfield County, with 2,347 in 2021.

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.