In 2020, Jefferson County, MT had a population of 12.1k people with a median age of 47.5 and a median household income of $71,779. Between 2019 and 2020 the population of Jefferson County, MT grew from 11,917 to 12,069, a 1.28% increase and its median household income grew from $69,646 to $71,779, a 3.06% increase.
The 5 largest ethnic groups in Jefferson County, MT are White (Non-Hispanic) (92.4%), Two+ (Non-Hispanic) (3.12%), White (Hispanic) (1.42%), Other (Hispanic) (1.2%), and American Indian & Alaska Native (Non-Hispanic) (1.01%).
None of the households in Jefferson County, MT reported speaking a non-English language at home as their primary shared language. This does not consider the potential multi-lingual nature of households, but only the primary self-reported language spoken by all members of the household.
99.3% of the residents in Jefferson County, MT are U.S. citizens.
In 2020, the median property value in Jefferson County, MT was $290,700, and the homeownership rate was 84.2%. Most people in Jefferson County, MT drove alone to work, and the average commute time was 22.1 minutes. The average car ownership in Jefferson County, MT was 3 cars per household.