St. Xavier: Demographics & People
St. Xavier's population stands at 55 people, in 32 households. Population shrank 28.6% from 77 (2022) to 55 (2024). Median age 40.8 years. (8.9y older than Big Horn County). Children under 18 are 27% of the population. Population is 62% White (non-Hispanic). The community is relatively homogeneous (Simpson index 0.00). 19% of households are family-led. County health: 41% adult obesity, 23% smoke.
- 1.7 people per household.
- 81% non-family households (singles, roommates).
Population & Trend
Population shrank 28.6% from 77 (2022) to 55 (2024). Estimated 2026 population: ~40 (extrapolated at -14.3%/yr trend). Census Bureau Vintage estimate: 25.
| Census data vintage | 2024 |
|---|---|
| Population | 13,124 people |
| Annual growth rate · Population change | -28.6% |
| Annual growth rate · Population (2022) | 77 |
| Annual growth rate · Population (2024) | 55 |
| Annual growth rate · Trend category | shrinking |
| Population | 55 people |
| Population Estimate | 25 |
Sources: Census ACS 5-Year 2023, Table B01003 · Refreshed 2026-04-12
Age Distribution
Median age 40.8y is 1.9 years older than the U.S. median (38.9y). Children under 18 make up 27% — above the U.S. share of ~22%.
| Age Summary · Median age | 40.8 years (at Montana median) |
|---|---|
| Age Summary · Children Pct | 27.3% |
| Age Summary · Character | established |
| Population under 18 | 15 |
| Median age | 40.8 years (at Montana median) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Race, Ethnicity & Diversity
Of 55 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.
| White residents | 33 |
|---|---|
| Diversity Index · Diversity label | relatively homogeneous |
| Diversity Index · Groups counted | 1 |
| Diversity Index · Largest group share | 100.0% |
| White (non-Hispanic) population | 61.8% |
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).
| Residents born in this state | 49 |
|---|---|
| Residents born in another state | 6 |
| Share born in this state | 89.1% |
| Share born in another state | 10.9% |
| Native-born U.S. citizens | 10.9% |
| Total foreign-born residents | 108 |
Households & Family Composition
32 households. Averaging 2.2 people each — smaller than the U.S. average of 2.5. 19% are family households — below the U.S. share of ~65%. Of 21 families, 38% are married couples with children.
| Children under 18 | 26 |
|---|---|
| Total families | 21 |
| Married couples with children | 8 |
| Average household size | 2.20 |
| Grandparents living with grandchildren | 1,296 |
| Grandparents responsible for grandchildren | 533 |
| Family households | 6 households |
| Households that are families | 18.8% |
| Total households | 32 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.
| Lived in same home a year ago | 55.0% |
|---|---|
| Migration · People moving in (annual) | 9,770 |
| Migration · People moving out (annual) | 9,790 |
| Migration · Net migration (in − out) | -20 |
| 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 | 10 |
|---|---|
| Disability rate | 12.8% |
Other
| Congressional District · District | 2 |
|---|---|
| Congressional District · Formatted | MT-02 |
| Congressional District · Congress | 118th |
| Cdc Birth Rate · Fips | 30,003 |
| Cdc Birth Rate · State Fips | 30 |
| Cdc Birth Rate · County Fips | 3 |
| Cdc Birth Rate · County | Big Horn |
| Cdc Birth Rate · Birth Rate | 63.8% |
| Cdc Birth Rate · Lower Ci | 54.20 |
| Cdc Birth Rate · Upper Ci | 74.40 |
| Cdc Mortality · Fips | 30,003 |
| Cdc Mortality · County | Big Horn County |
| Cdc Mortality · Urban Rural | Noncore |
| Cdc Mortality · Total Deaths 2020 2023 | 326 |
| Cdc Vaccination · Fips | 30,003 |
| Cdc Vaccination · County | Big Horn County |
| Cdc Vaccination · Dose1 Pop Pct | 95.0% |
| Cdc Vaccination · Series Complete Pct | 94.1% |
| Cdc Vaccination · Booster Pct | 39.8% |
| Cdc Vaccination · Population 2019 | 13,319 |
| Cdc Vaccination · Metro Status | Non-metro |
| Family Score · Score | 8.00 |
| Family Score · Schools | 14 |
| Family Score · Children Pct | 27.3% |
| Family Score · Rating | excellent |
| Town Summary · Key Facts | population 55, shrinking, established, high crime |
| Town Summary · Population | 55 people |
| Town Summary · County | Big Horn County |
Sources: Census place-to-CD118 crosswalk (place_fips) · federal dataset cascade