San Juan County, Washington Demographics 2026

Population Overview

San Juan County is located in Washington with a total population of 18,266. It is the 32nd most populous county out of 39 in Washington. The county encompasses 2 Census-designated places.

Age Demographics

The median age in San Juan County is 56.7 years. This is 48% higher than the state median of 38.2 years. Only 12.8% of residents are under 18, indicating fewer families with children. 13.4% 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 San Juan County is $83,682. This is 12% lower than the state median of $94,952. It is also 7% higher than the national median of $78,538. The poverty rate stands at 10.5%. This is 6% higher than the state poverty rate of 9.9%. The unemployment rate is 3.0%. This is 39% lower than the state rate of 5.0%. The median home value is $726,500. Housing costs are 40% higher than the state median of $519,800. The home-value-to-income ratio of 8.7x suggests that housing affordability is a significant concern for many residents. 77.8% of occupied housing units are owner-occupied. This homeownership rate is 22% higher than the state average of 63.9%.

Race & Ethnicity

San Juan County has a predominantly White (non-Hispanic) population, comprising 86.1% of all residents. Hispanic or Latino residents account for 7.5%. The Black or African American population (0.3%) is well below the state average of 3.8%. The Asian population (1.1%) is well below the state average of 9.3%.

Education

53.4% of residents aged 25 and older hold a bachelor's degree or higher. This places San Juan County in the top 10% of all counties in the state for educational attainment. This is 38% higher 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 95.5%. Notably, 22.8% of adults hold a graduate or professional degree, indicating a highly educated workforce.

Data Sources & Methodology

All figures for San Juan 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.