Adjacent counties

National protected area

• Lewis and Clark National Forest (part)
• Rocky Mountain Front Conservation Area (part)

2020 census

As of the 2020 census, there were 5,898 people living in the county.^{[citation needed]}

2010 census

As of the 2010 census, there were 6,153 people, 2,285 households, and 1,528 families residing in the county. The population density was 3.8 inhabitants per square mile (1.5/km²). There were 2,659 housing units at an average density of 1.6 units per square mile (0.62 units/km²). The racial makeup of the county was 82.7% white, 14.5% American Indian, 0.2% Asian, 0.1% black or African American, 0.2% from other races, and 2.4% from two or more races. Those of Hispanic or Latino origin made up 1.4% of the population. In terms of ancestry, 31.9% were German, 14.7% were Norwegian, 13.2% were Irish, 9.3% were English, 5.7% were Dutch, and 5.6% were American.

Of the 2,285 households, 30.0% had children under the age of 18 living with them, 53.3% were married couples living together, 9.4% had a female householder with no husband present, 33.1% were non-families, and 29.9% of all households were made up of individuals. The average household size was 2.41 and the average family size was 3.01. The median age was 42.8 years.

The median income for a household in the county was $36,419 and the median income for a family was $47,656. Males had a median income of $34,259 versus $26,903 for females. The per capita income for the county was $18,989. About 14.9% of families and 21.5% of the population were below the poverty line, including 32.5% of those under age 18 and 10.7% of those age 65 or over.

City

• Conrad (county seat)

Town

• Valier^[12]

Census-designated places

Other unincorporated communities