St. Pierre: Demographics & People
St. Pierre's population stands at 394 people, in 95 households. Population shrank 15.6% from 467 (2022) to 394 (2024). Median age 16.4 years. (18.1y younger than Hill County; 24.4y younger than Montana). Children under 18 are 55% of the population. Population is 1% Hispanic or Latino. The community is relatively homogeneous (Simpson index 0.00). 83% of households are family-led. County is losing 240 residents per year (2022-2023). County health: 35% adult obesity, 20% smoke.
- 4.1 people per household.
- 17% non-family households (singles, roommates).
Population & Trend
Population shrank 15.6% from 467 (2022) to 394 (2024). Estimated 2026 population: ~334 (extrapolated at -7.8%/yr trend). Census Bureau Vintage estimate: 265.
| Census data vintage | 2024 |
|---|---|
| Population | 16,309 people |
| Annual growth rate · Population change | -15.6% |
| Annual growth rate · Population (2022) | 467 |
| Annual growth rate · Population (2024) | 394 |
| Annual growth rate · Trend category | shrinking |
| Population | 394 people |
| Population Estimate | 265 |
Sources: Census ACS 5-Year 2023, Table B01003 · Refreshed 2026-04-12
Age Distribution
Median age 16.4y is 22.5 years younger than the U.S. median (38.9y). Children under 18 make up 55% — above the U.S. share of ~22%.
| Age Summary · Median age | 16.4 years (vs Montana 40.8y) |
|---|---|
| Age Summary · Children Pct | 54.6% |
| Age Summary · Character | young community |
| Population under 18 | 215 |
| Median age | 16.4 years (vs Montana 40.8y) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Race, Ethnicity & Diversity
Of 394 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.00 (0 = single group, 1 = perfectly even distribution); this is read as relatively homogeneous.
| Hispanic or Latino residents | 4 |
|---|---|
| Diversity Index · Diversity label | relatively homogeneous |
| Diversity Index · Groups counted | 1 |
| Diversity Index · Largest group share | 100.0% |
| Hispanic or Latino population | 1.3% |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Ancestry
Self-reported ancestry from Census ACS — what residents report as their ethnic origin, separate from race. Counts can exceed population because people can list multiple ancestries.
Top (1)
Citizenship & Origin
Where residents were born and their citizenship status (Census ACS). 5.6% are foreign-born — below the U.S. average of 13.9%.
| Residents born in this state | 317 |
|---|---|
| Residents born in another state | 55 |
| Share born in this state | 80.5% |
| Share born in another state | 19.5% |
| Native-born U.S. citizens | 14.0% |
| Foreign-born residents | 5.6% |
| Total foreign-born residents | 126 |
Households & Family Composition
95 households. Averaging 4.1 people each — larger than the U.S. average of 2.5. 83% are family households — above the U.S. share of ~65%. Of 100 families, 10% are married couples with children.
| Children under 18 | 208 |
|---|---|
| Total families | 100 |
| Married couples with children | 10 |
| Single-parent households | 32 |
| Average household size | 4.13 |
| Grandparents living with grandchildren | 15 |
| Family households | 79 households |
| Households that are families | 83.2% |
| Total households | 95 households |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Residential Stability & Migration
How long residents have lived here and where they came from. 15.2% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is losing 240 residents per year on net (IRS migration data).
| Moved within the county (past year) | 15.2% |
|---|---|
| Migration · People moving in (annual) | 14,195 |
| Migration · People moving out (annual) | 14,435 |
| Migration · Net migration (in − out) | -240 |
| Migration · Year | 2022-2023 |
Sources: IRS SOI Migration 2021-2022 · Refreshed 2026-04-12
Disability
Census ACS measures self-reported functional limitations — vision, hearing, mobility, cognitive, self-care, or independent-living. The U.S. baseline disability rate is about 12–13%; rates trend higher with median age.
| Residents with a disability | 16 |
|---|---|
| Disability rate | 3.7% |
Other
| Congressional District · District | 2 |
|---|---|
| Congressional District · Formatted | MT-02 |
| Congressional District · Congress | 118th |
| Cdc Birth Rate · Fips | 30,041 |
| Cdc Birth Rate · State Fips | 30 |
| Cdc Birth Rate · County Fips | 41 |
| Cdc Birth Rate · County | Hill |
| Cdc Birth Rate · Birth Rate | 45.1% |
| Cdc Birth Rate · Lower Ci | 37.50 |
| Cdc Birth Rate · Upper Ci | 53.80 |
| Cdc Mortality · Fips | 30,041 |
| Cdc Mortality · County | Hill County |
| Cdc Mortality · Urban Rural | Noncore |
| Cdc Mortality · Total Deaths 2020 2023 | 560 |
| Cdc Vaccination · Fips | 30,041 |
| Cdc Vaccination · County | Hill County |
| Cdc Vaccination · Dose1 Pop Pct | 84.6% |
| Cdc Vaccination · Series Complete Pct | 75.2% |
| Cdc Vaccination · Booster Pct | 60.6% |
| Cdc Vaccination · Population 2019 | 16,484 |
| Cdc Vaccination · Metro Status | Non-metro |
| Family Score · Score | 10 |
| Family Score · Schools | 19 |
| Family Score · Children Pct | 54.6% |
| Family Score · Rating | excellent |
| Town Summary · Key Facts | population 394, shrinking, young community, lower-income, white collar |
| Town Summary · Population | 394 people |
| Town Summary · County | Hill County |
Sources: Census place-to-CD118 crosswalk (place_fips) · federal dataset cascade