Big Arm, Montana Demographics & Population 2026
During the 2020–2024 ACS period, Big Arm, Montana had a total population of 190, the 257th largest community in Montana. The poverty rate is 50.0%.
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 (50.0%), well above the national average of 12.4%.
- Only 8.9% of adults have a bachelor's degree, well below the national average of 35.7%.
Big Arm Quick Facts
How Big Arm 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 | 142 | 190 | +33.8% |
How Big Arm 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+)
Big Arm Rankings in Montana
Explore Montana Rankings
Other Cities in Lake County
| City | Population | Median Income | Poverty | Home Value |
|---|---|---|---|---|
| Polson | 5,428 | $53,418 | 17.5% | $356,300 |
| Ronan | 2,001 | $42,298 | 21.6% | $225,500 |
| Pablo | 1,632 | $36,400 | 34.5% | $256,700 |
| St. Ignatius | 977 | $50,000 | 21.8% | $250,000 |
| Woods Bay | 835 | $64,091 | 10.5% | $512,200 |
| Arlee | 812 | $57,500 | 13.3% | $261,400 |
| Lindisfarne | 533 | N/A | 14.3% | $653,800 |
| Finley Point | 479 | $65,972 | 18.8% | $555,100 |
| Kerr | 463 | N/A | 27.9% | $558,200 |
| Charlo | 306 | $40,469 | 17.3% | $210,800 |
Cities Similar to Big Arm
These cities in the same state have comparable population and economic profiles.
| City | Population | Median Income | Home Value | Bachelor's+ | Poverty |
|---|---|---|---|---|---|
| Roberts | 191 | $95,917 | N/A | 15.6% | 19.4% |
| Riverview Colony | 192 | $2,499 | N/A | 0.0% | 82.8% |
| Denton | 193 | $56,667 | $157,800 | 24.5% | 6.7% |
| St. Mary | 193 | N/A | N/A | 38.2% | 61.9% |
| Crane | 187 | $79,545 | $230,300 | 52.8% | 0.0% |
A note before these figures: with a population of 190, Big Arm'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
Big Arm is a small community located in Montana, within Lake County. The total population is 190. It ranks as the 257th most populous out of 475 Census-designated places in Montana.
Age Demographics
The median age in Big Arm is 29.9 years. This is 26% lower than the state median of 40.4 years. With 35.3% of the population under 18, Big Arm has a notably young demographic profile, suggesting a family-oriented community.
Economy, Income & Housing
The poverty rate stands at 50.0%. This is 334% 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 survey records no unemployed residents in Big Arm, which reflects the size of the sample rather than a labor market without joblessness. 100.0% of occupied housing units are owner-occupied. This homeownership rate is 45% higher than the state average of 69.2%.
Race & Ethnicity
Big Arm is a highly diverse community where no single racial or ethnic group constitutes a majority of the population. The White (non-Hispanic) population (31.1%) is well below the state average of 83.6%.
Education
8.9% of residents aged 25 and older hold a bachelor's degree or higher. This is 75% lower than the state rate of 35.2%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 75.6%.
Data Sources & Methodology
All demographic data for Big Arm, 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 Big Arm, Montana?
Big Arm, Montana has a population of 190 according to the most recent U.S. Census ACS 5-Year Estimates.
What is the median household income in Big Arm, MT?
The Census Bureau does not publish a reliable median household income estimate for Big Arm — the community is too small for the ACS sample. The national median is $80,734.
What is the poverty rate in Big Arm, MT?
The poverty rate in Big Arm is 50.0%. This means approximately 95 residents live below the federal poverty line.
What is the racial makeup of Big Arm, Montana?
Big Arm's population is 31.1% White, 0.0% Black, 0.0% Hispanic/Latino, and 0.0% Asian.
What is the median home value in Big Arm, MT?
The Census Bureau does not publish a reliable median home value estimate for Big Arm — there are too few owner-occupied homes in the ACS sample. The national median is $332,700.
How educated is Big Arm, Montana?
8.9% of adults (25+) in Big Arm hold a bachelor's degree or higher, and 0.0% hold a graduate or professional degree.