Data / Rankings / Median age / Counties in Washington

Counties in Washington by median age

Jefferson County had the highest median age of 39 counties in 2021, at 59.3 years. Whitman County had the lowest, at 25 years. The median was 41.5 years and the figure for Washington was 37.9 years. Source: the U.S. Census Bureau.

Highest59.3Jefferson County
Lowest25Whitman County
Median41.539 counties
Washington37.9History

All counties, 2021

CSVChart (SVG)

Jefferson CountyJefferson County: 59.3 years59.3Wahkiakum CountyWahkiakum County: 56.7 years56.7San Juan CountySan Juan County: 56.5 years56.5Pacific CountyPacific County: 54.4 years54.4Clallam CountyClallam County: 50.8 years50.8Ferry CountyFerry County: 50.8 years50.8Garfield CountyGarfield County: 50.8 years50.8Columbia CountyColumbia County: 50.4 years50.4Pend Oreille CountyPend Oreille County: 50.3 years50.3Lincoln CountyLincoln County: 47.1 years47.1Stevens CountyStevens County: 46.7 years46.7Skamania CountySkamania County: 46.6 years46.6Klickitat CountyKlickitat County: 46.2 years46.2Asotin CountyAsotin County: 44.7 years44.7Mason CountyMason County: 44.7 years44.7Grays Harbor CountyGrays Harbor County: 44.4 years44.4Island CountyIsland County: 43.8 years43.8Okanogan CountyOkanogan County: 42.9 years42.9Lewis CountyLewis County: 42.5 years42.5Skagit CountySkagit County: 41.5 years41.5Cowlitz CountyCowlitz County: 40.8 years40.8Chelan CountyChelan County: 39.9 years39.9Kitsap CountyKitsap County: 39.4 years39.4Thurston CountyThurston County: 39.3 years39.3Clark CountyClark County: 38.7 years38.7Snohomish CountySnohomish County: 38.2 years38.2Spokane CountySpokane County: 37.9 years37.9Whatcom CountyWhatcom County: 37.8 years37.8Douglas CountyDouglas County: 37.5 years37.5Walla Walla CountyWalla Walla County: 37.5 years37.5King CountyKing County: 37.1 years37.1Pierce CountyPierce County: 36.4 years36.4Benton CountyBenton County: 36.1 years36.1Kittitas CountyKittitas County: 34.3 years34.3Grant CountyGrant County: 33.2 years33.2Yakima CountyYakima County: 33 years33Franklin CountyFranklin County: 30.5 years30.5Adams CountyAdams County: 28.3 years28.3Whitman CountyWhitman County: 25 years25
years. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2021
years
1Jefferson County59.3
2Wahkiakum County56.7
3San Juan County56.5
4Pacific County54.4
5Clallam County50.8
5Ferry County50.8
5Garfield County50.8
8Columbia County50.4
9Pend Oreille County50.3
10Lincoln County47.1
11Stevens County46.7
12Skamania County46.6
13Klickitat County46.2
14Asotin County44.7
14Mason County44.7
16Grays Harbor County44.4
17Island County43.8
18Okanogan County42.9
19Lewis County42.5
20Skagit County41.5
21Cowlitz County40.8
22Chelan County39.9
23Kitsap County39.4
24Thurston County39.3
25Clark County38.7
26Snohomish County38.2
27Spokane County37.9
28Whatcom County37.8
29Douglas County37.5
29Walla Walla County37.5
31King County37.1
32Pierce County36.4
33Benton County36.1
34Kittitas County34.3
35Grant County33.2
36Yakima County33
37Franklin County30.5
38Adams County28.3
39Whitman County25

Other periods

About this ranking

Age that divides the resident population into two halves of equal size. Spain and the EU: on 1 January. United States: American Community Survey five-year estimate, where the period shown is the last year of the five-year span.

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. American Community Survey 5-year estimates, table B01002: median age, total population. https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b01002.dat. Retrieved 2026-10-08.

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Questions

Which county has the highest median age?

Jefferson County, with 59.3 years in 2021, according to the U.S. Census Bureau.

Which county has the lowest median age?

Whitman County, with 25 years 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, American Community Survey 5-year estimates, table B01002: median age, total population. Retrieved 2026-10-08.

Median age: other rankings

Counties in Washington: more rankings