Jefferson County, Montana Demographics 2026

Population Overview

Jefferson County is located in Montana with a total population of 12,501. It is the 16th most populous county out of 56 in Montana.

Age Demographics

The median age in Jefferson County is 47.3 years. This is 18% higher than the state median of 40.2 years.

Economy, Income & Housing

The median household income in Jefferson County is $76,576. This is 10% higher than the state median of $69,922. Compared to the national median of $78,538, household income here is 2% lower. The poverty rate stands at 6.3%. This is 48% lower than the state poverty rate of 12.0%. The unemployment rate is 2.9%. This is 24% lower than the state rate of 3.8%. The median home value is $408,000. Housing costs are 21% higher than the state median of $338,100. The home-value-to-income ratio is 5.3x. 83.1% of occupied housing units are owner-occupied. This homeownership rate is 20% higher than the state average of 69.4%.

Race & Ethnicity

Jefferson County has a predominantly White (non-Hispanic) population, comprising 91.3% of all residents. Hispanic or Latino residents account for 2.7%. The Black or African American population (0.1%) is well below the state average of 0.5%.

Education

32.7% of residents aged 25 and older hold a bachelor's degree or higher. This is 5% lower than the state rate of 34.5%. Nationally, 35.0% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 94.0%.