Union Bridge, MD 21791 ZIP Code Profile

Related Place Profiles:
Linwood, MD | Union Bridge, MD

ZIP Code 21791: Basic Data & USPS Preferred City Name

Preferred Name, USPS
Union Bridge, MD 21791

Acceptable Alternative
Linwood, MD 21791

  • ZIP Code Type: STANDARD
  • County: Carroll County
  • Centroid: Latitude 39.545, Longitude -77.194
  • Time Zone: Eastern Time Zone (UTC -5 hours)
  • Observes DST: Yes

ZIP Code 21791 has segments in 2 Counties / Independent Cities (Carroll, Frederick).

  • Businesses Addresses: 76
  • PO Box Addresses: 273
  • Residential Addresses: 1,741
    • Multi-Family Addresses: 20
    • Single Family Addresses: 1,721

The ZIP Code maps and database are updated 4 times per year.
Database updated: May 1, 2018, Maps updated: February 1, 2018.

EXTREMELY LOCAL Demographic Data

Address Based Hyperlocal Data Input an address and get data & demographics for the pertinent census block group (CBG), a searchable map and a customized directory. The CBG is the smallest geographical unit used by the Census Bureau for reporting demographic data.


21791 ZIP Code Map

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Union Bridge, MD 21791 Data & Demographics (As of July 1, 2017)


Total Population 5,802
Daytime Population: Workers 1,077
Daytime Population: Residents 2,669
Total Daytime Population (TDP) 3,746
Ratio TDP/Total Population1 0.65
Population in Households 5,794
Population in Familes 5,004
Population in Group Qrtrs 8
Population Density2 111
Diversity Index3 16


Median Household Income $83,683
Average Household Income $98,334
Per Capita Income $35,506


Total Housing Units 2,302 (100%)
Owner Occupied HU 1,611 (70.0%)
Renter Occupied HU 481 (20.9%)
Vacant Housing Units 210 ( 9.1%)
Median Home Value $339,427
Average Home Value $385,583


Total Households 2,092
Average Household Size 2.77
Family Households 1,582
Average Family Size 3
  1. If the ratio of the TDP to Total Population is greater than 1, the location gains population during the day when commuting workers are present. If the ratio is less than 1, the location is more of a bedroom community where people commute to another place for work.
  2. Population Density = Total Population per square mile.
  3. The Diversity Index is a scale of 0 to 100 that represents the likelihood that two persons, chosen at random from the same area, belong to different race or ethnic groups. If an area's entire population belongs to one race AND one ethnic group, then the area has zero diversity. An area's diversity index increases to 100 when the population is evenly divided into two or more race/ethnic groups.


2010-2017 2017-2022
Population -0.01% 0.24%
Households -0.03% 0.21%
Families -0.12% 0.15%
Median Household Income   1.45%
Per Capita Income   2.36%

Union Bridge, MD 21791 - Peer Comparisons by Rank and Percentile

The table below compares 21791 to the other 456 ZIP Codes in Maryland by rank and percentile using July 1, 2017 data. The location Ranked # 1 has the highest value. A location that ranks higher than 75% of its peers would be in the 75th percentile of the peer group.

Variable Description Rank Percentile
Total Population # 227 50th
Population Density # 347 24th
Diversity Index # 399 13th
Median Household Income # 188 59th
Per Capita Income # 234 49th

Additional comparisons and rankings can be made with a VERY EASY TO USE Maryland Census Data Comparison Tool.

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