St. Mary, Montana Demographics & Population 2026
During the 2020–2024 ACS period, St. Mary, Montana had a total population of 193, the 253rd largest community in Montana. The poverty rate is 61.9%.
Data vintage: U.S. Census Bureau ACS 2020–2024 5-Year Estimates · refreshed July 2026 · Methodology & source notes
Key Takeaways
- More than 1 in 4 residents live below the poverty line (61.9%), well above the national average of 12.4%.
- Unemployment rate of 14.0% is notably above the national average.
St. Mary Quick Facts
How St. Mary Changed
Change from the 2019–2023 ACS period to 2020–2024. These are rolling five-year estimates, not year-over-year measurements.
| Metric | 2019–2023 | 2020–2024 | Change |
|---|---|---|---|
| Population | 209 | 193 | -7.7% |
How St. Mary Compares
Median Household Income
Median Home Value
Economy & Housing
Household Income Distribution
Detailed income brackets
Employment
Housing Overview
People & Demographics
Age Distribution
Race & Ethnicity
Diversity Index
A diverse community with significant representation from multiple racial and ethnic groups.
State average: 29 | National average: 61
Education
Educational Attainment (Adults 25+)
St. Mary Rankings in Montana
Explore Montana Rankings
Other Cities in Glacier County
| City | Population | Median Income | Poverty | Home Value |
|---|---|---|---|---|
| North Browning | 3,144 | $37,155 | 43.3% | $187,500 |
| Cut Bank | 3,028 | $49,432 | 18.9% | $164,100 |
| South Browning | 1,538 | N/A | 42.2% | $73,000 |
| Browning | 943 | $34,250 | 46.4% | $151,800 |
| Glacier Colony | 404 | N/A | 58.2% | N/A |
| East Glacier Park Village | 271 | $53,182 | 9.0% | $194,300 |
| Starr School | 235 | $72,596 | 33.6% | $162,500 |
| Babb | 223 | N/A | 15.7% | $187,500 |
| Little Browning | 102 | $26,563 | 21.6% | N/A |
| Blackfoot | 85 | N/A | 0.0% | N/A |
Cities Similar to St. Mary
These cities in the same state have comparable population and economic profiles.
| City | Population | Median Income | Home Value | Bachelor's+ | Poverty |
|---|---|---|---|---|---|
| Denton | 193 | $56,667 | $157,800 | 24.5% | 6.7% |
| Riverview Colony | 192 | $2,499 | N/A | 0.0% | 82.8% |
| Roberts | 191 | $95,917 | N/A | 15.6% | 19.4% |
| Big Arm | 190 | N/A | N/A | 8.9% | 50.0% |
| Custer | 199 | $82,500 | $137,500 | 29.9% | 20.1% |
A note before these figures: with a population of 193, St. Mary's ACS estimates come from a small number of survey responses and carry wide margins of error. Individual percentages below — particularly rates that round to 0% or 100% — are approximations, not precise measurements. See data.census.gov for the published margins of error.
Population Overview
St. Mary is a small community located in Montana, within Glacier County. The total population is 193. It ranks as the 253rd most populous out of 475 Census-designated places in Montana.
Age Demographics
The median age in St. Mary is 25.8 years. This is 36% lower than the state median of 40.4 years. Only 10.4% of residents are under 18, indicating fewer families with children.
Economy, Income & Housing
The poverty rate stands at 61.9%. This is 437% higher than the state poverty rate of 11.5%. With more than one in five residents living below the poverty line, economic hardship is a significant challenge for the community. The unemployment rate is 14.0%. This is 286% higher than the state rate of 3.6%. 73.1% of occupied housing units are owner-occupied. This homeownership rate is 6% higher than the state average of 69.2%.
Race & Ethnicity
The largest racial or ethnic group in St. Mary is White (non-Hispanic), making up 53.4% of the population. Hispanic or Latino residents account for 23.8%. The Hispanic or Latino population is significantly higher than the state average (23.8% vs 4.6%).
Education
38.2% of residents aged 25 and older hold a bachelor's degree or higher. This is 9% higher than the state rate of 35.2%. Nationally, 35.7% of adults hold at least a bachelor's degree. No surveyed resident aged 25 or older reported leaving school before earning a high school diploma, though a rate of exactly 100% reflects the limits of a small sample. Notably, 20.0% of adults hold a graduate or professional degree, indicating a highly educated workforce.
Data Sources & Methodology
All demographic data for St. Mary, Montana is sourced from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates. The ACS collects data from approximately 3.5 million households annually and pools five years of responses so that even small communities can be measured, though the margin of error widens as the population falls. Comparisons are made against Montana state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 475 Census-designated places in Montana. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.
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Frequently Asked Questions
What is the population of St. Mary, Montana?
St. Mary, Montana has a population of 193 according to the most recent U.S. Census ACS 5-Year Estimates.
What is the median household income in St. Mary, MT?
The Census Bureau does not publish a reliable median household income estimate for St. Mary — the community is too small for the ACS sample. The national median is $80,734.
What is the poverty rate in St. Mary, MT?
The poverty rate in St. Mary is 61.9%. This means approximately 107 residents live below the federal poverty line.
What is the racial makeup of St. Mary, Montana?
St. Mary's population is 53.4% White, 0.0% Black, 23.8% Hispanic/Latino, and 0.0% Asian.
What is the median home value in St. Mary, MT?
The Census Bureau does not publish a reliable median home value estimate for St. Mary — there are too few owner-occupied homes in the ACS sample. The national median is $332,700.
How educated is St. Mary, Montana?
38.2% of adults (25+) in St. Mary hold a bachelor's degree or higher, and 20.0% hold a graduate or professional degree.