Columbia County, Washington Demographics 2026

Population Overview

Columbia County is located in Washington with a total population of 3,996. It is the 38th most populous county out of 39 in Washington. The county encompasses 2 Census-designated places.

Age Demographics

The median age in Columbia County is 52.1 years. This is 36% higher than the state median of 38.2 years. 12.6% of residents are 75 or older, suggesting a significant retirement-age population with implications for healthcare services and senior housing.

Economy, Income & Housing

The median household income in Columbia County is $71,528. This is 25% lower than the state median of $94,952. It is also 9% lower than the national median of $78,538. The poverty rate stands at 9.0%. This is 9% lower than the state poverty rate of 9.9%. The unemployment rate is 3.4%. This is 32% lower than the state rate of 5.0%. The median home value is $256,100. Housing costs are 51% lower than the state median of $519,800. The home-value-to-income ratio is 3.6x. 77.8% of occupied housing units are owner-occupied. This homeownership rate is 22% higher than the state average of 63.9%.

Race & Ethnicity

The largest racial or ethnic group in Columbia County is White (non-Hispanic), making up 81.5% of the population. Hispanic or Latino residents account for 8.2%. The Black or African American population (0.7%) is well below the state average of 3.8%. The Asian population (0.0%) is well below the state average of 9.3%.

Education

27.2% of residents aged 25 and older hold a bachelor's degree or higher. This is 30% lower than the state rate of 38.8%. Nationally, 35.0% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 88.9%.

Data Sources & Methodology

All figures for Columbia County come from the U.S. Census Bureau's American Community Survey (ACS) 5-Year Estimates (2019-2023), with comparisons drawn against Washington and national averages from the same dataset. See our methodology page for how each metric is defined, or data.census.gov for official tables with margins of error.