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

Cowlitz County is a county in Washington with a population of 111,539. It ranks #12 among counties in Washington by population. The median age is 41.1, older than the national median. The population is 50.1% male and 49.9% female.

The median household income in Cowlitz County is $72,932, near the US median of $74,580. 8.5% of residents live below the federal poverty level. Home values sit at a median of $367,400, with monthly rent averaging $1,169. The homeownership rate of 66.2% is close to the national rate of 64.8%.

Educational attainment in Cowlitz County reflects 17.0% of adults 25 and older holding a bachelor's degree or higher, below the national average of 34.3%. Roughly 7.3% of workers primarily work from home, below the national work-from-home rate of 14.2%. The average commute is 26.5 minutes each way.

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

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.