Data / Rankings / Median age / Counties in Washington

Counties in Washington by median age, 2024

Jefferson County had the highest median age of 39 counties in 2024, at 59.8 years. Whitman County had the lowest, at 26.4 years. The median was 42.1 years and the figure for Washington was 38.3 years. Source: the U.S. Census Bureau.

Highest59.8Jefferson County
Lowest26.4Whitman County
Median42.139 counties
Washington38.3History

All counties, 2024

CSVChart (SVG)

Jefferson CountyJefferson County: 59.8 years59.8San Juan CountySan Juan County: 57 years57Pacific CountyPacific County: 55 years55Wahkiakum CountyWahkiakum County: 54.5 years54.5Ferry CountyFerry County: 52.9 years52.9Clallam CountyClallam County: 52.1 years52.1Pend Oreille CountyPend Oreille County: 49.8 years49.8Columbia CountyColumbia County: 49.6 years49.6Skamania CountySkamania County: 48.5 years48.5Garfield CountyGarfield County: 47.8 years47.8Lincoln CountyLincoln County: 46.9 years46.9Stevens CountyStevens County: 46.9 years46.9Klickitat CountyKlickitat County: 46.8 years46.8Asotin CountyAsotin County: 46.2 years46.2Island CountyIsland County: 44.8 years44.8Grays Harbor CountyGrays Harbor County: 44.7 years44.7Mason CountyMason County: 44.7 years44.7Okanogan CountyOkanogan County: 43.2 years43.2Lewis CountyLewis County: 42.2 years42.2Skagit CountySkagit County: 42.1 years42.1Cowlitz CountyCowlitz County: 41.5 years41.5Chelan CountyChelan County: 40.4 years40.4Kitsap CountyKitsap County: 40.2 years40.2Thurston CountyThurston County: 40 years40Clark CountyClark County: 39.1 years39.1Douglas CountyDouglas County: 38.9 years38.9Snohomish CountySnohomish County: 38.6 years38.6Spokane CountySpokane County: 38.5 years38.5Walla Walla CountyWalla Walla County: 38.5 years38.5Whatcom CountyWhatcom County: 38.4 years38.4King CountyKing County: 37.4 years37.4Pierce CountyPierce County: 37 years37Benton CountyBenton County: 36.3 years36.3Kittitas CountyKittitas County: 35.8 years35.8Grant CountyGrant County: 33.7 years33.7Yakima CountyYakima County: 33.3 years33.3Franklin CountyFranklin County: 30.9 years30.9Adams CountyAdams County: 29.3 years29.3Whitman CountyWhitman County: 26.4 years26.4
years. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2024
years		Change on 2023
1Jefferson County59.8+0.3
2San Juan County57+0.3
3Pacific County55+0.1
4Wahkiakum County54.5-0.3
5Ferry County52.9+0.1
6Clallam County52.1+0.3
7Pend Oreille County49.8-0.2
8Columbia County49.6-2.5
9Skamania County48.5-0.1
10Garfield County47.8-4.8
11Lincoln County46.90
11Stevens County46.9+0.1
13Klickitat County46.8-0.7
14Asotin County46.2+0.7
15Island County44.8+0.3
16Grays Harbor County44.70
16Mason County44.7-0.1
18Okanogan County43.2-0.2
19Lewis County42.2-0.2
20Skagit County42.1+0.2
21Cowlitz County41.5+0.4
22Chelan County40.40
23Kitsap County40.2+0.3
24Thurston County40+0.2
25Clark County39.1+0.2
26Douglas County38.9+0.5
27Snohomish County38.6+0.2
28Spokane County38.5+0.3
28Walla Walla County38.5+0.2
30Whatcom County38.4+0.2
31King County37.4+0.1
32Pierce County37+0.2
33Benton County36.3+0.1
34Kittitas County35.8-2.1
35Grant County33.7+0.2
36Yakima County33.3+0.1
37Franklin County30.9+0.1
38Adams County29.3+0.1
39Whitman County26.4+0.3

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/2024/table-based-SF/data/5YRData/acsdt5y2024-b01002.dat. Retrieved 2026-10-08.

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Questions

Which county has the highest median age?

Jefferson County, with 59.8 years in 2024, according to the U.S. Census Bureau.

Which county has the lowest median age?

Whitman County, with 26.4 years in 2024.

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