Lewis County, Idaho Demographics 2026

Population Overview

Lewis County is located in Idaho with a total population of 3,649. It is the 41st most populous county out of 44 in Idaho.

Age Demographics

The median age in Lewis County is 48.9 years. This is 32% higher than the state median of 37.1 years. 10.8% 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 Lewis County is $49,643. This is 33% lower than the state median of $74,636. Compared to the national median of $78,538, household income here is 37% lower. The poverty rate stands at 17.4%. This is 63% higher than the state poverty rate of 10.6%. The unemployment rate is 3.5%. This is 6% lower than the state rate of 3.7%. The median home value is $202,400. Housing costs are 46% lower than the state median of $376,000. The home-value-to-income ratio is 4.1x. 74.2% of occupied housing units are owner-occupied. This homeownership rate is 3% higher than the state average of 72.4%.

Race & Ethnicity

The largest racial or ethnic group in Lewis County is White (non-Hispanic), making up 82.2% of the population. Hispanic or Latino residents account for 4.1%. The Black or African American population is significantly higher than the state average (1.7% vs 0.7%). The Hispanic or Latino population (4.1%) is well below the state average of 13.3%.

Education

20.0% of residents aged 25 and older hold a bachelor's degree or higher. This is 36% lower than the state rate of 31.2%. Nationally, 35.0% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 90.8%.