Skip to main content
Population Review

Cowlitz County, Washington Population 2026

Updated April 2026 · US Census ACS 2023 5-Year Estimates · 12th-largest in Washington

The population of Cowlitz County, Washington is 111,539 as of the 2023 American Community Survey, making it the 12th-largest county in Washington. The median household income is $72,932, the median home value is $367,400, and the median age is 41.1.

The population of Cowlitz County has grown 11.4% since 2010 (102,358 → 113,982), a +0.77% annualized rate.

Cowlitz County within Washington · Source: US Census TIGER/Line via us-atlas

111,539

Population

+0.77%

Annual growth

98

People / sq mi

$72,932

Median Income

$367,400

Median Home Value

Cowlitz County covers 1,141 sq mi of land at 97.7 people per square mile.

About Cowlitz County, WA

Housing cost is the defining feature of Cowlitz County: the median home is valued at $367,400. With 111,539 residents, Cowlitz County is a county in Washington. It ranks #12 among counties in Washington by population.

Median household income is $72,932, below the US median of $78,538. Poverty runs at 8.5%, below the national 12.4%. Real estate commands a premium here — a median home value of $367,400, with typical rent around $1,169.

Fewer adults hold degrees here than in most comparable places — 17.0%, below the national 35.0%. Around 7.3% of workers work from home, below the national 14.0%, and the average commute runs about 27 minutes each way.

High housing values reframe the income picture in Cowlitz County — even solid earnings stretch less against home prices and rents at this level.

Cowlitz County Population History (2010-2024)

The county of Cowlitz County had a population of 102,358 in 2010 and 113,982 in 2024, a 11.4% growth over 14 years. The peak was 113,982 in 2024. Average annual growth rate: 0.77%.

2024 · 114K20102024
Cowlitz County population, 2010–2024 · Source: U.S. Census Bureau — decennial census & Population Estimates

113,982

Population (2024)

102,358

Population (2010)

113,982

Peak (2024)

0.77%

Avg Annual Growth

YearPopulation
2010102,358
2011102,313
2012101,669
2013101,497
2014101,811
2015103,031
2016104,760
2017106,800
2018108,673
2019110,389
2020111,021
2021111,701
2022112,058
2023113,040
2024113,982

Race & Ethnicity

White84.8%
Black or African American0.7%
Asian0.0%
Hispanic or Latino (any race)4.1%
Two or More Races0.1%

Age & Sex

41.1

Median Age

49.9%

Female

50.1%

Male

19.5%

Age 65+

Age Distribution

Under 5
5.7%
5–9
6.3%
10–14
6.6%
15–19
6.0%
20–24
5.4%
25–34
12.7%
35–44
12.2%
45–54
11.9%
55–59
6.6%
60–64
7.0%
65–74
11.7%
75–84
5.9%
85+
1.9%

Children (under 15): 18.6% · Seniors (65+): 19.5%

Income & Poverty

Median household income$72,932$-22,020 vs state
Mean household income$92,523
Per-capita income$36,520
Poverty rate8.5%+2.1% vs state
Unemployment rate2.8%
Employment-to-population52.4%

Top Industries by Employment

Professional & business services
20.9%
Manufacturing
14.3%
Construction
9.3%
Finance & real estate
9.1%
Education & health care
8.2%
Retail trade
7.5%
Public administration
5.4%
Arts, entertainment & food
4.6%

The largest employment sector in Cowlitz County is professional & business services, accounting for 20.9% of workers.

How residents commute

0.5%

Drive alone

1.0%

Carpool

82.6%

Public transit

7.3%

Work from home

26.5 min

Avg commute

Housing

$367,400$-152,400 vs state

Median home value

$1,169

Median rent

66.2%

Homeownership rate

45,884

Total housing units

94.6%

Occupied

5.4%

Vacant

33.8%

Renter-occupied

Social & access

93.9%

With health insurance

94.8%

With broadband internet

42.8%

Foreign-born

10.2%

Veterans (18+)

19.4%

With a disability

92.2%

Speak language other than English at home

Education

89.9%

High School+

17.0%

Bachelor's+

Largest cities in Washington

Other counties in Washington

Part of Washington

Metro areas in Washington

County rankings

Frequently Asked Questions

Cowlitz County, Washington has a population of 111,539 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 12th-largest county in Washington. Population density is 98 people per square mile.

The population of Cowlitz County has grown 11.4% since 2010 (102,358 → 113,982), a +0.77% annualized rate.

The median household income in Cowlitz County, Washington is $72,932, with mean (average) household income of $92,523 and per-capita income of $36,520. 8.5% of residents live below the federal poverty level.

In Cowlitz County, the largest racial and ethnic groups are White (84.8%), Hispanic or Latino (4.1%), Black or African American (0.7%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.

The median age in Cowlitz County, Washington is 41.1 years. Residents are 49.9% female and 50.1% male.

The median home value in Cowlitz County is $367,400 and median monthly rent is $1,169. 66.2% of occupied housing units are owner-occupied. The county has 45,884 total housing units, 5.4% of which are vacant.

The largest employment sector in Cowlitz County, Washington is professional, scientific, and management services, employing 20.9% of workers. The unemployment rate is 2.8%.

Seattle is among the largest cities associated with Cowlitz County, Washington, with a population of 741,440.

Data from the American Community Survey (ACS) 5-Year estimates.

Source: U.S. Census Bureau ACS, 2026.