Stillwater County's 2026 population is estimated at 9,876, reflecting a 2.2% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Stillwater County is the 25th largest county in Montana. The 2010 population was 9,112 and has grown 8.38% since 2010.
Data after 2023 is projected based on recent change
Overall: 46.7 years
Female: 46.8 years
Male: 46.6 years
There are 7,257 adults, (2,314 of whom are seniors) in Stillwater County.
Female: 4,542 (49.5%)
Male: 4,640 (50.5%)
The racial composition of Stillwater County includes 93.04% White, and smaller percentages for other race, Asian, Native American, Black or African American and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 8,543 | 93.04% |
| Two or more races | 508 | 5.53% |
| Other race | 68 | 0.74% |
| Asian | 34 | 0.37% |
| Native American | 25 | 0.27% |
| Black or African American | 4 | 0.04% |
Stillwater County 's average per capita income is $49,848. Household income levels show a median of $84,732. The poverty rate stands at 8.27%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $113,156 | - |
| Families | $106,458 | $138,133 |
| Households | $84,732 | $116,762 |
| Non Families | $39,710 | $70,767 |
Average Income
Median Household Income
Poverty Rate
