Columbia County, Washington Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 38th-largest in Washington
The population of Columbia County, Washington is 3,996 as of the 2023 American Community Survey, making it the 38th-largest county in Washington. The median household income is $71,528, the median home value is $256,100, and the median age is 52.1.
The population of Columbia County has declined 1.7% since 2010 (4,094 → 4,025), a -0.12% annualized rate.
3,996
Population
-0.12%
Annual growth
5
People / sq mi
$71,528
Median Income
$256,100
Median Home Value
Columbia County covers 869 sq mi of land at 4.6 people per square mile.
About Columbia County, WA
Columbia County is a county in Washington with a population of 3,996. It ranks #38 among counties in Washington by population. The median age is 52.1, older than the national median. The population is 50.3% male and 49.7% female.
The median household income in Columbia County is $71,528, near the US median of $74,580. 4.2% of residents live below the federal poverty level. Home values sit at a median of $256,100, with monthly rent averaging $944. The homeownership rate of 77.9% is higher than the national rate of 64.8%.
Educational attainment in Columbia County reflects 27.2% of adults 25 and older holding a bachelor's degree or higher, below the national average of 34.3%. Roughly 5.1% of workers primarily work from home, below the national work-from-home rate of 14.2%. The average commute is 20.5 minutes each way.
Columbia County Population History (2010-2024)
The county of Columbia County had a population of 4,094 in 2010 and 4,025 in 2024, a -1.7% growth over 14 years. The peak was 4,094 in 2010. Average annual growth rate: -0.12%.
4,025
Population (2024)
4,094
Population (2010)
4,094
Peak (2010)
-0.12%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 4,094 |
| 2011 | 4,005 |
| 2012 | 3,977 |
| 2013 | 4,002 |
| 2014 | 3,984 |
| 2015 | 3,961 |
| 2016 | 3,983 |
| 2017 | 4,010 |
| 2018 | 4,055 |
| 2019 | 4,023 |
| 2020 | 3,953 |
| 2021 | 4,019 |
| 2022 | 4,018 |
| 2023 | 4,055 |
| 2024 | 4,025 |
Race & Ethnicity
| White | 81.5% |
| Black or African American | 0.7% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 7.1% |
| Two or More Races | 0.0% |
Age & Sex
52.1
Median Age
49.7%
Female
50.3%
Male
29.7%
Age 65+
Age Distribution
Children (under 15): 15.4% · Seniors (65+): 29.7%
Income & Poverty
| Median household income | $71,528$-23,424 vs state |
| Mean household income | $89,990 |
| Per-capita income | $42,143 |
| Poverty rate | 4.2%-2.2% vs state |
| Unemployment rate | 1.9% |
| Employment-to-population | 52.8% |
Top Industries by Employment
The largest employment sector in Columbia County is professional & business services, accounting for 22.7% of workers.
How residents commute
0.5%
Drive alone
6.6%
Carpool
75.6%
Public transit
5.1%
Work from home
20.5 min
Avg commute
Housing
$256,100$-263,700 vs state
Median home value
$944
Median rent
77.9%
Homeownership rate
2,218
Total housing units
85.3%
Occupied
14.7%
Vacant
22.1%
Renter-occupied
Social & access
91.2%
With health insurance
92.0%
With broadband internet
32.5%
Foreign-born
11.2%
Veterans (18+)
19.8%
With a disability
92.6%
Speak language other than English at home
Education
88.9%
High School+
27.2%
Bachelor's+
Largest cities in Washington
Other counties in Washington
Part of Washington
Metro areas in Washington
County rankings
Frequently Asked Questions
Columbia County, Washington has a population of 3,996 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 38th-largest county in Washington. Population density is 5 people per square mile.
The population of Columbia County has declined 1.7% since 2010 (4,094 → 4,025), a -0.12% annualized rate.
The median household income in Columbia County, Washington is $71,528, with mean (average) household income of $89,990 and per-capita income of $42,143. 4.2% of residents live below the federal poverty level.
In Columbia County, the largest racial and ethnic groups are White (81.5%), Hispanic or Latino (7.1%), 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 Columbia County, Washington is 52.1 years. Residents are 49.7% female and 50.3% male.
The median home value in Columbia County is $256,100 and median monthly rent is $944. 77.9% of occupied housing units are owner-occupied. The county has 2,218 total housing units, 14.7% of which are vacant.
The largest employment sector in Columbia County, Washington is professional, scientific, and management services, employing 22.7% of workers. The unemployment rate is 1.9%.
Seattle is among the largest cities associated with Columbia County, Washington, with a population of 741,440.
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Full rankings of Washington counties
Statewide data for Washington
Population, race, income, age, and trends across Washington
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.