2020 census
As of the 2020 census, the county had a population of 9,371. [12]
Of the residents, 19.7% were under the age of 18 and 24.1% were 65 years of age or older; the median age was 43.9 years. For every 100 females there were 102.0 males, and for every 100 females age 18 and over there were 101.1 males. 47.3% of residents lived in urban areas and 52.7% lived in rural areas. [13]
The racial makeup of the county was 90.2% White, 0.3% Black or African American, 1.4% American Indian and Alaska Native, 0.4% Asian, 1.5% from some other race, and 6.1% from two or more races. Hispanic or Latino residents of any race comprised 4.6% of the population. [12]
There were 4,108 households in the county, of which 22.9% had children under the age of 18 living with them and 23.8% had a female householder with no spouse or partner present. About 32.9% of all households were made up of individuals and 14.6% had someone living alone who was 65 years of age or older. [14]
There were 4,918 housing units, of which 16.5% were vacant. Among occupied housing units, 65.1% were owner-occupied and 34.9% were renter-occupied. The homeowner vacancy rate was 1.9% and the rental vacancy rate was 8.2%. [14]
2010 census
As of the 2010 census, there were 9,246 people, 4,014 households, and 2,383 families living in the county. The population density was 1.7 inhabitants per square mile (0.66/km2). There were 5,273 housing units at an average density of 1.0 per square mile (0.39/km2). The racial makeup of the county was 94.8% white, 1.4% American Indian, 0.4% Pacific islander, 0.4% Asian, 0.2% black or African American, 1.2% from other races, and 1.6% from two or more races. Those of Hispanic or Latino origin made up 3.7% of the population. In terms of ancestry, 26.5% were German, 23.9% were English, 15.4% were Irish, 7.9% were Norwegian, 6.5% were Scottish, and 3.4% were American.
Of the 4,014 households, 23.8% had children under the age of 18 living with them, 49.9% were married couples living together, 6.4% had a female householder with no husband present, 40.6% were non-families, and 33.0% of all households were made up of individuals. The average household size was 2.19 and the average family size was 2.79. The median age was 42.0 years.
The median income for a household in the county was $38,264 and the median income for a family was $53,036. Males had a median income of $35,568 versus $27,314 for females. The per capita income for the county was $21,110. About 10.8% of families and 15.0% of the population were below the poverty line, including 14.4% of those under age 18 and 6.0% of those age 65 or over.
United States
Montana 
