ZIP code 21791: Union Bridge, MD
21791 is a ZIP code in Union Bridge, Maryland, mainly in Frederick County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metro area. About 5,340 people live here.
- Population
- 5,340
- Median household income
- $93,015
- Typical home value
- $444,900+0.5% in 12 months
- Median rent
- $1,457gross, per month
- Median age
- 37.7
- Homeowners
- 81.7%of occupied homes
Shaded: ZIP code 21791's area. Click anywhere on the map to see which ZIP code it's in.
ZIP codes within 10 milesWithin 25 miles
ZIP code 21791 details
| City | Union Bridge |
|---|---|
| State | Maryland |
| County | Frederick County (also partly Carroll County) |
| Metro area | Washington-Arlington-Alexandria, DC-VA-MD-WV |
| Time zone | Eastern Time (UTC−5), observes daylight saving time |
| Type | Standard (delivery area) |
| Land area | 46 sq mi, plus 0.1 sq mi of water |
| Population density | 116 people per sq mi |
| Bachelor's degree or higher | 26.7% of adults 25+ |
| Average commute | 37.3 minutes |
| Center coordinates | 39.53305, -77.18856 |
Median rent in 21791 by bedrooms
| Size | Median gross rent |
|---|---|
| 1 bedroom | $725/mo |
| 2 bedrooms | $1,280/mo |
| 3 bedrooms | $1,518/mo |
| 4 bedrooms | $1,719/mo |
Gross rent includes utilities paid by the tenant. ACS 2020–2024; sizes with too few rentals to estimate are left out.
ZIP codes near 21791
| ZIP code | City | Distance | Population |
|---|---|---|---|
| 21792 | Unionville, MD | 4.0 mi | — |
| 21762 | Libertytown, MD | 4.8 mi | 139 |
| 21776 | New Windsor, MD | 4.8 mi | 6,261 |
| 21757 | Keymar, MD | 5.6 mi | 2,671 |
| 21798 | Woodsboro, MD | 5.7 mi | 2,928 |
| 21759 | Ladiesburg, MD | 6.0 mi | — |
| 21775 | New Midway, MD | 6.1 mi | — |
| 21793 | Walkersville, MD | 8.8 mi | 10,719 |
Population and median household income: ACS 2020–2024 5-year estimates. Typical home value: Zillow Home Value Index (September 2026) where available, otherwise the ACS median owner-reported value. "PO Box" marks ZIP codes with no delivery area of their own. Methodology
Buying a home in 21791?
A typical home in ZIP code 21791 is worth about $444,900 (Zillow Home Value Index). The median household here earns $93,015 a year. See what buying here would cost per month, with Maryland average taxes and insurance filled in.
Monthly payment for a $444,900 homeWhat can a $93,015 income afford?Rental property numbers
About ZIP code 21791
What city is ZIP code 21791?
ZIP code 21791 is in Union Bridge, MD, in Frederick County.
What county is ZIP code 21791 in?
21791 is mainly in Frederick County, Maryland, and partly in Carroll County.
What is the population of ZIP code 21791?
About 5,340 people live in ZIP code 21791, according to the American Community Survey 2020–2024 5-year estimates.
What time zone is ZIP code 21791 in?
21791 is in Eastern Time (UTC−5). It observes daylight saving time.