St. Marys, Ohio demographics

St. Marys, OH demographics: median age 36.6; 17.5% of adults 25+ hold a bachelor’s degree. Age, race, households, languages and education, ACS 2020–2024 with margins of error.

ACS 2020–2024 · St. Marys city, Ohio · Incorporated city · GEOID 3969680. The survey estimates a population of 8,301 for its five-year window. This is separate from the annual July 2025 population estimate on the city overview.

Median age in St. Marys is 36.6 years, with a 90% margin of error of 3.2 years. There are 3,408 households (±221). Age and household distributions show how these totals are composed; they do not establish which neighborhood suits a particular person.

Every count and share is an estimate. “±” is a 90% margin of error (MOE); pp means percentage points. Derived shares use the category count divided by the named universe. Aggregated category MOEs and percentage MOEs are approximate. A margin larger than half its estimate is flagged as low precision. Blank source uncertainty is shown as unavailable, never zero.

Age distribution and sex

City, state and U.S. estimates · ACS 2020–2024
Measure / survey universe	City estimate ± MOE	State estimate ± MOE	U.S. estimate ± MOE
Median age Total population · years	36.6 ±3.2	39.7 ±0.2	38.9 ±0.1

Age groups · B01001 · ACS 2020–2024 Total population: 8,301
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
Under 18	2,018 ±306	24.3% ±3.6 pp	22.0%	22.0%
18–34	1,928 ±312	23.2% ±3.7 pp	22.1%	22.8%
35–64	2,984 ±427	35.9% ±5.1 pp	37.7%	38.0%
65 and older	1,371 ±228	16.5% ±2.7 pp	18.3%	17.2%

Sex categories as published by ACS · B01001 · ACS 2020–2024 Total population: 8,301
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
Male	4,159 ±266	50.1% ±2.9 pp	49.3%	49.5%
Female	4,142 ±249	49.9% ±2.7 pp	50.7%	50.5%

The age groups are mutually exclusive and cover the entire population. The sex categories follow this ACS table’s published classification; they are not a survey of gender identity.

Race and Hispanic origin

Race · B02001 · ACS 2020–2024 Total population: 8,301
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
White alone	7,569 ±361	91.2% ±3.5 pp	76.8%	61.0%
Black or African American alone	142 ±121 · low precision	1.7% ±1.5 pp · low precision	12.2%	12.2%
American Indian and Alaska Native alone	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.2%	0.9%
Asian alone	11 ±18 · low precision	0.1% ±0.2 pp · low precision	2.6%	6.0%
Native Hawaiian and Other Pacific Islander alone	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.0%	0.2%
Some other race alone	15 ±43 · low precision	0.2% ±0.5 pp · low precision	1.8%	7.1%
Two or more races	564 ±279	6.8% ±3.4 pp	6.5%	12.6%

Hispanic or Latino origin · B03003 · ACS 2020–2024 Total population: 8,301
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
Not Hispanic or Latino	7,811 ±344	94.1% ±3.2 pp	95.2%	80.7%
Hispanic or Latino	490 ±278 · low precision	5.9% ±3.3 pp · low precision	4.8%	19.3%

Hispanic origin and race are separate questions. People of Hispanic or Latino origin may be of any race and appear in both tables. Do not add the Hispanic share to race shares. Race alone and two-or-more-race groups are the mutually exclusive categories of the race table.

Household types, children and living alone

Household types · B11001 · ACS 2020–2024 Households: 3,408
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
Married-couple family	1,747 ±229	51.3% ±5.8 pp	44.4%	46.9%
Other family: male householder, no spouse present	227 ±120 · low precision	6.7% ±3.5 pp · low precision	4.8%	5.1%
Other family: female householder, no spouse present	214 ±114 · low precision	6.3% ±3.3 pp · low precision	12.0%	12.2%
Nonfamily: householder living alone	998 ±242	29.3% ±6.8 pp	32.0%	28.7%
Nonfamily: householder not living alone	222 ±98	6.5% ±2.8 pp	6.8%	7.0%

Households with children · B11005 · ACS 2020–2024 Households: 3,408
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
Households with people under 18	1,071 ±168	31.4% ±4.5 pp	28.0%	29.5%
Households without people under 18	2,337 ±329	68.6% ±8.6 pp	72.0%	70.5%

Household size · B11016 · ACS 2020–2024 Households: 3,408
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
One-person nonfamily households	998 ±242	29.3% ±6.8 pp	32.0%	28.7%
Two-person households	1,223 ±253	35.9% ±7.0 pp	34.6%	33.8%
Three-person households	437 ±176	12.8% ±5.1 pp	14.1%	15.3%
Four-person households	415 ±203	12.2% ±5.9 pp	11.3%	12.6%
Five-person households	227 ±96	6.7% ±2.8 pp	5.1%	5.9%
Six-person households	32 ±31 · low precision	0.9% ±0.9 pp · low precision	1.8%	2.2%
Seven or more people	76 ±83 · low precision	2.2% ±2.4 pp · low precision	1.1%	1.4%

A family household contains related people under the Census definition. A nonfamily household can contain one person or unrelated people sharing a home. Households with children can also appear in the household-type and size tables, so those tables must not be added together. Household estimates exclude people living in group quarters from the household universe.

Nativity and languages spoken at home

Nativity · B05002 · ACS 2020–2024 Total population: 8,301
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
Native	8,290 ±234	99.9% ±0.5 pp	94.8%	85.9%
Foreign born	11 ±18 · low precision	0.1% ±0.2 pp · low precision	5.2%	14.1%

Language spoken at home · C16001 · ACS 2020–2024 Population age 5 and older: 7,709
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
English only	7,685 ±289	99.7% ±5.3 pp	92.0%	77.7%
Spanish	15 ±43 · low precision	0.2% ±0.6 pp · low precision	2.6%	13.6%
French, Haitian, or Cajun	9 ±15 · low precision	0.1% ±0.2 pp · low precision	0.3%	0.7%
German or other West Germanic	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.9%	0.5%
Russian, Polish, or other Slavic	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.4%	0.7%
Other Indo-European	0 ±18 · low precision	0.0% ±0.2 pp · low precision	1.2%	2.0%
Korean	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.1%	0.3%
Chinese, including Mandarin and Cantonese	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.4%	1.1%
Vietnamese	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.1%	0.5%
Tagalog, including Filipino	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.1%	0.6%
Other Asian and Pacific Island	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.6%	1.1%
Arabic	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.4%	0.5%
Other and unspecified	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.7%	0.8%

Foreign born means not a U.S. citizen at birth; it includes naturalized citizens. Language categories describe speech at home among people age five and older. A language other than English at home does not establish that someone cannot speak English. This city page uses the published C16001 summary categories because the more detailed B16001 table does not provide these city records in this release.

Educational attainment

Highest completed education · B15003 · ACS 2020–2024 Population age 25 and older: 5,376
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
Less than high school graduate	208 ±101	3.9% ±1.9 pp	8.2%	10.4%
High school graduate or equivalency	2,355 ±385	43.8% ±6.8 pp	32.1%	26.0%
Some college, no degree	1,084 ±310	20.2% ±5.7 pp	19.3%	19.1%
Associate’s degree	788 ±214	14.7% ±3.9 pp	9.0%	8.8%
Bachelor’s degree	678 ±195	12.6% ±3.6 pp	19.3%	21.6%
Graduate or professional degree	263 ±162 · low precision	4.9% ±3.0 pp · low precision	12.2%	14.1%

The denominator excludes residents under 25. Each person is counted in the highest attainment category they completed. This table does not measure the quality of local schools or the education level of every current student.

Residence one year earlier

Geographic mobility · B07003 · ACS 2020–2024 Population age 1 and older: 8,169
Category	Count ± MOE	Share ± MOE (pp)	Ohio	U.S.
Same house	7,283 ±423	89.2% ±4.4 pp	88.1%	87.7%
Moved within same county	500 ±260 · low precision	6.1% ±3.2 pp · low precision	6.7%	6.3%
Moved from a different county in the same state	304 ±180 · low precision	3.7% ±2.2 pp · low precision	3.2%	3.1%
Moved from a different state	82 ±78 · low precision	1.0% ±1.0 pp · low precision	1.6%	2.3%
Moved from abroad	0 ±18 · low precision	0.0% ±0.2 pp · low precision	0.4%	0.6%

These are respondents’ residence patterns one year before their survey response, pooled across the five-year window. They are not a net migration count for 2025. A person can move to a different house within the same city or county; moves within the same county should not automatically be interpreted as new arrivals to the city.

Health insurance, internet access and veterans

5.0% of St. Marys residents (±2.1 percentage points) had no health insurance coverage when surveyed, compared with 6.4% in Ohio and 8.4% nationally. 91.2% of households subscribe to broadband of any type, including cellular data plans. A subscription is not the same as available service: the FCC National Broadband Map shows providers at a specific address.

City, state and U.S. shares · ACS 2020–2024
Measure	St. Marys	Ohio	U.S.	Compared with Ohio
People without health insurance Civilian noninstitutionalized population	5.0% ±2.1 pp	6.4%	8.4%	Not statistically different
Households with a broadband subscription Households	91.2% ±3.4 pp	90.1%	91.0%	Not statistically different
Veterans Civilian population age 18 and older	8.9% ±2.9 pp	6.6%	6.2%	Not statistically different

Reading and reusing the estimates

The Census table links above lead to the original detailed tables. Counts, source universes and uncertainty are retained in the source observation download for St. Marys . Compare these figures with the same survey window; do not compare one city’s five-year estimate with another city’s annual estimate as though they measured the same period. For methods, see uncertainty and denominator calculations.

Read St. Marys housing and cost context or return to the city profile.