St. Mary is a CDP located in Glacier County, Montana. St. Mary has a 2025 population of 303. St. Mary is currently growing at a rate of 7.45% annually but its population has decreased by -47.67% since the most recent census, which recorded a population of 579 in 2020.
The median age in St. Mary is 22 years: 21.6 years for males, and 24.6 years for females.
Data after 2023 is projected based on recent change
The racial composition of St. Mary includes 77.51% White, 8.13% Native American, 7.18% Native Hawaiian or Pacific Islander, 7.18% other race, and smaller percentages for and multiracial populations.
Race | Population | Percentage (of total) |
---|---|---|
White | 162 | 77.51% |
Native American | 17 | 8.13% |
Native Hawaiian or Pacific Islander | 15 | 7.18% |
Other race | 15 | 7.18% |
Married
Widowed
Divorced
Separated
Never Married