St. Clair: Demographics & People
5,585 people call St. Clair home, in 2,404 households. Population grew 0.1% from 5,581 (2022) to 5,585 (2024). Median age 42.0 years. (2.5y younger than St. Clair County; 1.7y older than Michigan). Children under 18 are 24% of the population. Population is 92% White (non-Hispanic) and 4% Black. 62% of households are family-led. County is gaining 1,610 residents per year (2022-2023). County health: 41% adult obesity, 16% smoke.
- 2.3 people per household.
- 38% non-family households (singles, roommates).
Population & Trend
Population grew 0.1% from 5,581 (2022) to 5,585 (2024) — close to the U.S. annual rate of ~0.6%/yr. Estimated 2026 population: ~5,588 (extrapolated at 0.0%/yr trend).
| Census data vintage | 2024 |
|---|---|
| Population | 160,383 people |
| Annual growth rate · Population change | 0.1% |
| Annual growth rate · Population (2022) | 5,581 |
| Annual growth rate · Population (2024) | 5,585 |
| Annual growth rate · Population growing | Yes |
| Annual growth rate · Trend category | stable |
| Population | 5,585 people |
| Population Estimate | 5,594 |
Sources: Census ACS 5-Year 2023, Table B01003 · Refreshed 2026-04-12
Age Distribution
Median age 42.0y is 3.1 years older than the U.S. median (38.9y). Children under 18 make up 24% — above the U.S. share of ~22%.
| Age Summary · Median age | 42.0 years (vs Michigan 40.3y) |
|---|---|
| Age Summary · Children Pct | 23.7% |
| Age Summary · Character | established |
| Population under 18 | 1,323 |
| Median age | 42.0 years (vs Michigan 40.3y) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Race, Ethnicity & Diversity
Of 5,585 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups).
| White residents | 5,299 |
|---|---|
| Black residents | 109 |
| Hispanic or Latino residents | 121 |
| Diversity Index · Simpson Index | 9.9% |
| Diversity Index · Interpretation | less diverse |
| Black population | 3.7% |
| Hispanic or Latino population | 1.7% |
| White (non-Hispanic) population | 92.1% |
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). 0.9% are foreign-born — below the U.S. average of 13.9%. 2% have naturalized to U.S. citizenship.
| Residents born in this state | 4,967 |
|---|---|
| Residents born in another state | 472 |
| Share born in this state | 88.9% |
| Share born in another state | 11.1% |
| Native-born U.S. citizens | 8.5% |
| Foreign-born residents | 0.9% |
| Naturalized citizens | 1.7% |
| Total foreign-born residents | 145 |
| From Europe | 58 |
| From Africa | 22 |
Households & Family Composition
2,404 households. Averaging 2.4 people each — smaller than the U.S. average of 2.5. 62% are family households — below the U.S. share of ~65%. Of 1,590 families, 25% are married couples with children.
| Children under 18 | 1,188 |
|---|---|
| Total families | 1,590 |
| Married couples with children | 397 |
| Single-parent households | 11 |
| Average household size | 2.37 |
| Women who gave birth (past year) | 20.1% |
| Grandparents living with grandchildren | 61 |
| Grandparents responsible for grandchildren | 15 |
| Family households | 1,496 households |
| Households that are families | 62.2% |
| Total households | 2,404 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. 11.0% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is gaining 1,610 residents per year on net (IRS migration data).
| Moved within the county (past year) | 11.0% |
|---|---|
| Migration · People moving in (annual) | 147,763 |
| Migration · People moving out (annual) | 146,153 |
| Migration · Net migration (in − out) | 1,610 |
| Migration · Population growing | Yes |
| 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 | 345 |
|---|---|
| Disability rate | 6.3% |
Group Quarters
Group quarters are non-household living arrangements counted by the Census — college dormitories, nursing homes, military barracks, group homes, correctional facilities, and similar institutional or shared housing. 18 residents live in group quarters (0.3% of population).
| Living in group quarters | 18 |
|---|
Other
| Congressional District · District | 9 |
|---|---|
| Congressional District · Formatted | MI-09 |
| Congressional District · Congress | 118th |
| Cdc Birth Rate · Fips | 26,147 |
| Cdc Birth Rate · State Fips | 26 |
| Cdc Birth Rate · County Fips | 147 |
| Cdc Birth Rate · County | St Clair |
| Cdc Birth Rate · Birth Rate | 15.7% |
| Cdc Birth Rate · Lower Ci | 14.00 |
| Cdc Birth Rate · Upper Ci | 17.60 |
| Cdc Mortality · Fips | 26,147 |
| Cdc Mortality · County | St. Clair County |
| Cdc Mortality · Urban Rural | Large fringe metro |
| Cdc Mortality · Total Deaths 2020 2023 | 6,638 |
| Cdc Vaccination · Fips | 26,147 |
| Cdc Vaccination · County | St. Clair County |
| Cdc Vaccination · Dose1 Pop Pct | 51.9% |
| Cdc Vaccination · Series Complete Pct | 50.2% |
| Cdc Vaccination · Booster Pct | 52.6% |
| Cdc Vaccination · Population 2019 | 159,128 |
| Cdc Vaccination · Metro Status | Metro |
| Family Score · Score | 10 |
| Family Score · Schools | 20 |
| Family Score · Children Pct | 23.7% |
| Family Score · Rating | excellent |
| Town Summary · Key Facts | population 5,585, stable, established, middle-class, mixed |
| Town Summary · Population | 5,585 people |
| Town Summary · County | St. Clair County |
Sources: Census place-to-CD118 crosswalk (place_fips) · federal dataset cascade