St. Mary's: Demographics & People
St. Mary's is home to 810 people, in 248 households. Population grew 2.8% from 788 (2022) to 810 (2024). Median age 28.1 years. (4.5y older than Kusilvak Census Area; 7.8y younger than Alaska). Children under 18 are 32% of the population. Population is 6% White (non-Hispanic) and 1% Hispanic or Latino. The community is somewhat diverse (Simpson index 0.23). 74% of households are family-led. County is losing 483 residents per year (2022-2023). County health: 46% adult obesity, 38% smoke.
- 3.3 people per household.
- 26% non-family households (singles, roommates).
Population & Trend
Population grew 2.8% from 788 (2022) to 810 (2024) — about 4.7× the recent U.S. annual rate of ~0.6%/yr. Estimated 2026 population: ~832 (extrapolated at 1.4%/yr trend). Census Bureau Vintage estimate: 863.
| Census data vintage | 2024 |
|---|---|
| Population | 8,368 people |
| Annual growth rate · Population change | 2.8% |
| Annual growth rate · Population (2022) | 788 |
| Annual growth rate · Population (2024) | 810 |
| Annual growth rate · Population growing | Yes |
| Annual growth rate · Trend category | growing |
| Population | 810 people |
| Population Estimate | 863 |
Sources: Census ACS 5-Year 2023, Table B01003 · Refreshed 2026-04-12
Age Distribution
Median age 28.1y is 10.8 years younger than the U.S. median (38.9y). Children under 18 make up 32% — above the U.S. share of ~22%.
| Age Summary · Median age | 28.1 years (vs Alaska 35.9y) |
|---|---|
| Age Summary · Children Pct | 32.2% |
| Age Summary · Character | young community |
| Population under 18 | 261 |
| Median age | 28.1 years (vs Alaska 35.9y) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Race, Ethnicity & Diversity
Of 810 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.23 (0 = single group, 1 = perfectly even distribution); this is read as somewhat diverse.
| White residents | 39 |
|---|---|
| Hispanic or Latino residents | 6 |
| Diversity Index · Diversity index (Simpson) | 23.1% |
| Diversity Index · Diversity label | somewhat diverse |
| Diversity Index · Groups counted | 2 |
| Diversity Index · Largest group share | 86.7% |
| Hispanic or Latino population | 0.9% |
| White (non-Hispanic) population | 6.5% |
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 (6)
Citizenship & Origin
Where residents were born and their citizenship status (Census ACS). 1.4% are foreign-born — below the U.S. average of 13.9%. 1% have naturalized to U.S. citizenship.
| Residents born in this state | 739 |
|---|---|
| Residents born in another state | 51 |
| Share born in this state | 91.2% |
| Share born in another state | 8.8% |
| Native-born U.S. citizens | 6.3% |
| Foreign-born residents | 1.4% |
| Naturalized citizens | 1.1% |
| Total foreign-born residents | 3 |
Households & Family Composition
248 households. Averaging 3.2 people each — larger than the U.S. average of 2.5. 74% are family households — above the U.S. share of ~65%. Of 184 families, 35% are married couples with children.
| Children under 18 | 268 |
|---|---|
| Total families | 184 |
| Married couples with children | 64 |
| Single-parent households | 16 |
| Average household size | 3.23 |
| Women who gave birth (past year) | 5.2% |
| Grandparents living with grandchildren | 37 |
| Grandparents responsible for grandchildren | 27 |
| Family households | 183 households |
| Households that are families | 73.8% |
| Total households | 248 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. 8.4% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is losing 483 residents per year on net (IRS migration data).
| Moved within the county (past year) | 8.4% |
|---|---|
| Migration · People moving in (annual) | 5,433 |
| Migration · People moving out (annual) | 5,916 |
| Migration · Net migration (in − out) | -483 |
| 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 | 46 |
|---|---|
| Disability rate | 4.6% |
Other
| Congressional District · District | at-large |
|---|---|
| Congressional District · Formatted | AK-AL |
| Congressional District · Congress | 118th |
| Cdc Vaccination · Fips | 2,158 |
| Cdc Vaccination · County | Kusilvak Census Area |
| Cdc Vaccination · Dose1 Pop Pct | 74.8% |
| Cdc Vaccination · Series Complete Pct | 69.2% |
| Cdc Vaccination · Booster Pct | 48.5% |
| Cdc Vaccination · Population 2019 | 8,314 |
| Cdc Vaccination · Metro Status | Non-metro |
| Family Score · Score | 6.00 |
| Family Score · Schools | 12 |
| Family Score · Children Pct | 32.2% |
| Family Score · Rating | good |
| Town Summary · Key Facts | population 810, growing, young community, middle-class, mixed |
| Town Summary · Population | 810 people |
| Town Summary · County | Kusilvak Census Area |
Sources: Census place-to-CD118 crosswalk (place_fips) · federal dataset cascade