County Maps US

Cowlitz County, Washington

A county in Washington, ranked 12 of 39 by population.

CountyFIPS 53015

Within Washington
Cowlitz County, highlighted, with the areas around it. Boundaries generalised from the 2025 Census cartographic boundary file; neighbour fills carry no data. The dot marks Kelso, the county seat, located via the 2025 Census Gazetteer.

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Population
114,885
+3,871 (+3.5%) since 2020
Land area
1,141
square miles. A further 2.2% of the total area is water
Population density
101
people per square mile, computed rather than published
County seat
Kelso
Seat of county government.
Established
1854
171 years ago
Largest city
Longview city
Population 38,362.

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; Wikidata (CC0), Wikidata. Retrieved 30 August 2026.

Satellite view

Aerial imagery of Cowlitz County with its boundary drawn on top. A map shows you the shape; this shows you what is inside it, and which side of the line a place falls on.

Aerial view of Cowlitz County, Washington from the USGS National Map, with its boundary outlined
Imagery: USGS National Map, USGS Imagery Only, public domain, requested from USGS by your browser when you reach this point on the page, at 800 by 652 pixels. The boundary is the 2025 Census cartographic boundary file, reprojected to Web Mercator to match the imagery. You can also open the USGS National Map viewer.

Where Cowlitz County ranks

Position among the 39 counties of Washington, and among all 3,144 US counties and county-equivalents. Computed from the figures on this page.

MeasureValueIn WashingtonNationally
Population114,88512th of 39560th of 3,144
Land area1,141 sq mi28th of 39544th of 3,144
Population density101 per sq mi12th of 39900th of 3,144
Median household income$76,53118th of 39746th of 3,143

Full data for Cowlitz County

Every figure below is attributed to the Census Bureau product it came from, with the vintage of that product.
MeasureValueSource and vintage
Population114,885Vintage 2025 Population Estimates
Population in 2020111,014Vintage 2025 Population Estimates
2020 estimates base?110,728Vintage 2025 Population Estimates
Land area1,141 sq mi2025 Gazetteer Files
Water area25.2 sq mi2025 Gazetteer Files
Total area1,166 sq mi2025 Gazetteer Files
Population density?101 per sq miComputed: Vintage 2025 estimates divided by 2025 Gazetteer land area
Median household income$76,531American Community Survey 2020-2024 5-Year Estimates
Median home value$397,500American Community Survey 2020-2024 5-Year Estimates
Median age41.5American Community Survey 2020-2024 5-Year Estimates
Households43,943American Community Survey 2020-2024 5-Year Estimates
Housing units46,422American Community Survey 2020-2024 5-Year Estimates

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026. Population density is computed here, not published: it divides the Vintage 2025 population estimate by the 2025 Gazetteer land area, which are two different Census products. Retrieved 30 August 2026.

How the population changed

The Census Bureau publishes the components behind an estimate, not just the total. For the year to July 2025:

Births minus deaths
-44
1,302 births, 1,346 deaths
Net migration
+1,174
More people moved in than moved out.

Source: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026. Retrieved 30 August 2026.

The 5 areas bordering Cowlitz County

Ordered by the length of the border actually shared, which the Census Bureau publishes in its county adjacency file and which no other county reference presents.

Bordering areaStateShared borderPopulation
Lewis CountyWashington47 mi88,062
Clark CountyWashington47 mi532,119
Columbia CountyOregon35 mi54,091
Skamania CountyWashington23 mi12,669
Wahkiakum CountyWashington15 mi4,873

Source: US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. Retrieved 30 August 2026.

All 39 counties of Washington

Open the interactive Washington county map, or jump straight to any of them.

Data on this page last rebuilt 30 August 2026. How these figures are produced.