St. Clair: Demographics & People
710 people call St. Clair home, in 254 households. Population shrank 9.6% from 785 (2022) to 710 (2024). Median age 43.4 years. (11.8y older than Blue Earth County; 4.4y older than Minnesota). Children under 18 are 25% of the population. Population is 86% White (non-Hispanic) and 5% Hispanic or Latino. The community is relatively homogeneous (Simpson index 0.20). 76% of households are family-led. County is losing 1,616 residents per year (2022-2023). County health: 42% adult obesity, 18% smoke.
- 2.8 people per household.
- 24% non-family households (singles, roommates).
Population & Trend
Population shrank 9.6% from 785 (2022) to 710 (2024). Estimated 2026 population: ~643 (extrapolated at -4.8%/yr trend). Census Bureau Vintage estimate: 561.
| Census data vintage | 2024 |
|---|---|
| Population | 69,112 people |
| Annual growth rate · Population change | -9.6% |
| Annual growth rate · Population (2022) | 785 |
| Annual growth rate · Population (2024) | 710 |
| Annual growth rate · Trend category | shrinking |
| Population | 710 people |
| Population Estimate | 561 |
Sources: Census ACS 5-Year 2023, Table B01003 · Refreshed 2026-04-12
Age Distribution
Median age 43.4y is 4.5 years older than the U.S. median (38.9y). Children under 18 make up 25% — above the U.S. share of ~22%.
| Age Summary · Median age | 43.4 years (vs Minnesota 39.0y) |
|---|---|
| Age Summary · Children Pct | 24.8% |
| Age Summary · Character | established |
| Population under 18 | 176 |
| Median age | 43.4 years (vs Minnesota 39.0y) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Race, Ethnicity & Diversity
Of 710 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.20 (0 = single group, 1 = perfectly even distribution); this is read as relatively homogeneous.
| White residents | 696 |
|---|---|
| Black residents | 41 |
| Asian residents | 8 |
| Hispanic or Latino residents | 34 |
| Diversity Index · Diversity index (Simpson) | 19.7% |
| Diversity Index · Diversity label | relatively homogeneous |
| Diversity Index · Groups counted | 4 |
| Diversity Index · Largest group share | 89.3% |
| Asian population | 0.3% |
| Hispanic or Latino population | 4.6% |
| White (non-Hispanic) population | 86.5% |
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 (8)
Citizenship & Origin
Where residents were born and their citizenship status (Census ACS).
| Residents born in this state | 576 |
|---|---|
| Residents born in another state | 129 |
| Share born in this state | 81.1% |
| Share born in another state | 18.9% |
| Native-born U.S. citizens | 18.2% |
| Naturalized citizens | 0.7% |
| Total foreign-born residents | 7 |
| From Europe | 2 |
| From Africa | 2 |
Households & Family Composition
254 households. Averaging 2.9 people each — larger than the U.S. average of 2.5. 76% are family households — above the U.S. share of ~65%. Of 206 families, 45% are married couples with children.
| Children under 18 | 223 |
|---|---|
| Total families | 206 |
| Married couples with children | 92 |
| Single-parent households | 13 |
| Average household size | 2.88 |
| Women who gave birth (past year) | 10.5% |
| Grandparents living with grandchildren | 372 |
| Grandparents responsible for grandchildren | 104 |
| Family households | 194 households |
| Households that are families | 76.4% |
| Total households | 254 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. 5.3% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is losing 1,616 residents per year on net (IRS migration data).
| Moved within the county (past year) | 5.3% |
|---|---|
| Migration · People moving in (annual) | 60,220 |
| Migration · People moving out (annual) | 61,836 |
| Migration · Net migration (in − out) | -1,616 |
| 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 | 27 |
|---|---|
| Disability rate | 3.4% |
Other
| Congressional District · District | 1 |
|---|---|
| Congressional District · Formatted | MN-01 |
| Congressional District · Congress | 118th |
| Cdc Birth Rate · Fips | 27,013 |
| Cdc Birth Rate · State Fips | 27 |
| Cdc Birth Rate · County Fips | 13 |
| Cdc Birth Rate · County | Blue Earth |
| Cdc Birth Rate · Birth Rate | 5.9% |
| Cdc Birth Rate · Lower Ci | 4.70 |
| Cdc Birth Rate · Upper Ci | 7.20 |
| Cdc Mortality · Fips | 27,013 |
| Cdc Mortality · County | Blue Earth County |
| Cdc Mortality · Urban Rural | Small metro |
| Cdc Mortality · Total Deaths 2020 2023 | 2,299 |
| Cdc Vaccination · Fips | 27,013 |
| Cdc Vaccination · County | Blue Earth County |
| Cdc Vaccination · Dose1 Pop Pct | 67.0% |
| Cdc Vaccination · Series Complete Pct | 63.1% |
| Cdc Vaccination · Booster Pct | 59.6% |
| Cdc Vaccination · Population 2019 | 67,653 |
| Cdc Vaccination · Metro Status | Metro |
| Family Score · Score | 10 |
| Family Score · Schools | 20 |
| Family Score · Children Pct | 24.8% |
| Family Score · Rating | excellent |
| Town Summary · Key Facts | population 710, shrinking, established, affluent, mixed |
| Town Summary · Population | 710 people |
| Town Summary · County | Blue Earth County |
Sources: Census place-to-CD118 crosswalk (place_fips) · federal dataset cascade