Custer County's 2026 population is estimated at 12,091, reflecting a 0.47% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Custer County is the 17th largest county in Montana. The 2010 population was 11,691 and has grown 3.42% since 2010.
Overall: 42.7 years
Female: 44.2 years
Male: 42.4 years
There are 9,592 adults, (2,482 of whom are seniors) in Custer County.
Female: 5,939 (49.7%)
Male: 6,022 (50.3%)
The racial composition of Custer County includes 90.44% White, and smaller percentages for Native American, other race, Asian, Black or African American and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 10,817 | 90.44% |
| Two or more races | 798 | 6.67% |
| Native American | 220 | 1.84% |
| Other race | 68 | 0.57% |
| Asian | 54 | 0.45% |
| Black or African American | 4 | 0.03% |
Custer County 's average per capita income is $42,436. Household income levels show a median of $70,605. The poverty rate stands at 11.34%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $100,476 | - |
| Families | $92,841 | $103,556 |
| Households | $70,605 | $85,295 |
| Non Families | $36,214 | $51,614 |
Average Income
Median Household Income
Poverty Rate