Lemhi County, Idaho Demographics 2026

Population Overview

Lemhi County is located in Idaho with a total population of 8,249. It is the 33rd most populous county out of 44 in Idaho. The county encompasses 2 Census-designated places.

Age Demographics

The median age in Lemhi County is 53.3 years. This is 43% higher than the state median of 37.3 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 Lemhi County is $53,202. This is 32% lower than the state median of $77,800. It is also 34% lower than the national median of $80,734. The poverty rate stands at 12.8%. This is 21% higher than the state poverty rate of 10.6%. The unemployment rate is 2.0%. This is 46% lower than the state rate of 3.7%. The median home value is $326,100. Housing costs are 22% lower than the state median of $418,600. The home-value-to-income ratio of 6.1x suggests that housing affordability is a significant concern for many residents. 79.3% of occupied housing units are owner-occupied. This homeownership rate is 10% higher than the state average of 72.1%.

Race & Ethnicity

Lemhi County has a predominantly White (non-Hispanic) population, comprising 91.5% of all residents. Hispanic or Latino residents account for 3.9%. The Black or African American population (0.1%) is well below the state average of 0.7%. The Hispanic or Latino population (3.9%) is well below the state average of 13.7%. The Asian population (0.0%) is well below the state average of 1.3%.

Education

24.1% of residents aged 25 and older hold a bachelor's degree or higher. This is 24% lower than the state rate of 31.8%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 90.8%.

Data Sources & Methodology

All figures for Lemhi County come from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates, with comparisons drawn against Idaho 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.