St. Mary's County, Maryland
St. Mary's County, Maryland, had an estimated population of 116,692 in 2025 across 929 km². The figures below come from the US Census Bureau's population estimates and the American Community Survey, each shown with its own vintage and its rank among Maryland's counties and nationally.
- Population
- 116,692
- 2025 estimate
- Area
- 929 km²
- Density
- 126
- per km²
- Median income
- $119,446
- household, ACS 2024
- Median age
- 37.2
- years, ACS 2024
How Maryland's counties spread
Amenities & Infrastructure
| Indicator | Value | In Maryland | In the US |
|---|---|---|---|
| Households with Broadband2024 | 93.1% | 8 / 24 | 251 / 3,144 |
| Median Gross Rent2024 | $1,747 | 8 / 24 | 117 / 3,137 |
| Median Home Value2024 | $407,600 | 11 / 24 | 275 / 3,139 |
| Owner-Occupied Homes2024 | 73.2% | 12 / 24 | 1,805 / 3,144 |
| Vacant Homes2024 | 8.5% | 10 / 24 | 2,436 / 3,144 |
Demography
| Indicator | Value | In Maryland | In the US |
|---|---|---|---|
| Aged 65 and Over2024 | 14.0% | 23 / 24 | 2,900 / 3,144 |
| American Indian & Alaska Native2024 | 0.1% | 6 / 24 | 1,566 / 3,144 |
| Asian, non-Hispanic2024 | 2.6% | 9 / 24 | 396 / 3,144 |
| Average Household Size2024people | 2.7 | 8 / 24 | 472 / 3,144 |
| Black, non-Hispanic2024 | 14.6% | 11 / 24 | 590 / 3,144 |
| Foreign-Born2024 | 4.3% | 19 / 24 | 1,122 / 3,144 |
| Hispanic or Latino2024 | 6.1% | 13 / 24 | 1,355 / 3,144 |
| Median Age2024years | 37.2 | 22 / 24 | 2,637 / 3,144 |
| Sex Ratio2024per 1,000 males | 983 | 20 / 24 | 1,962 / 3,144 |
| Speak a Language Other Than English2024 | 7.3% | 14 / 24 | 1,230 / 3,144 |
| Under 182024 | 23.9% | 1 / 24 | 718 / 3,144 |
| Veterans2024 | 14.4% | 1 / 24 | 59 / 3,144 |
| White, non-Hispanic2024 | 70.3% | 13 / 24 | 2,035 / 3,144 |
Economy
| Indicator | Value | In Maryland | In the US |
|---|---|---|---|
| Below Poverty Line2024 | 8.0% | 15 / 24 | 2,775 / 3,144 |
| Households on SNAP2024 | 11.2% | 13 / 24 | 1,675 / 3,144 |
| Income Inequality2024index | 0.409 | 19 / 24 | 2,749 / 3,144 |
| Median Household Income2024 | $119,446 | 7 / 24 | 56 / 3,143 |
| Per Capita Income2024 | $53,417 | 8 / 24 | 156 / 3,144 |
| Unemployment Rate2024 | 3.6% | 19 / 24 | 2,074 / 3,144 |
Education
| Indicator | Value | In Maryland | In the US |
|---|---|---|---|
| Bachelor's Degree or Higher2024 | 36.5% | 13 / 24 | 394 / 3,144 |
| High School or Higher2024 | 92.7% | 11 / 24 | 842 / 3,144 |
Health Coverage
| Indicator | Value | In Maryland | In the US |
|---|---|---|---|
| No Health Insurance2024 | 3.9% | 17 / 24 | 2,883 / 3,144 |
| With a Disability2024 | 11.9% | 14 / 24 | 2,689 / 3,144 |
Population & Density
| Indicator | Value | In Maryland | In the US |
|---|---|---|---|
| Population2025 | 116,692 | 12 / 24 | 552 / 3,144 |
| Population Density2025/km² | 126 | 13 / 24 | 407 / 3,144 |
Work & Commute
| Indicator | Value | In Maryland | In the US |
|---|---|---|---|
| Commute by Public Transit2024 | 0.9% | 12 / 24 | 453 / 3,144 |
| Households with No Vehicle2024 | 3.2% | 22 / 24 | 2,671 / 3,144 |
| Mean Commute Time2024minutes | 29.9 | 10 / 24 | 501 / 3,143 |
| Work from Home2024 | 17.5% | 8 / 24 | 234 / 3,144 |
Other counties of Maryland
- Allegany County
- Anne Arundel County
- Baltimore County
- Baltimore city
- Calvert County
- Caroline County
- Carroll County
- Cecil County
- Charles County
- Dorchester County
- Frederick County
- Garrett County
- Harford County
- Howard County
- Kent County
- Montgomery County
- Prince George's County
- Queen Anne's County
- Somerset County
- Talbot County
- Washington County
- Wicomico County
- Worcester County
Compare St. Mary's County against every other county on a map, add layers and run a scatter — open the atlas. Sources and vintages for every figure on this page are listed under datasets, or browse all 3,144 counties.