US > Maryland > Carroll County > Union Bridge, MD 21791

21791 ZIP Code Profile, Map, Data & Demographics

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

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: 68
  • PO Box Addresses: 239
  • Residential Addresses: 1,812
    • Multi-Family Addresses: 21
    • Single Family Addresses: 1,791

The ZIP Code maps and database are updated 4 times per year.
Database updated: June 1, 2025, Maps updated: May 1, 2024.

Advertisement

Union Bridge, MD 21791 Data & Demographics (As of July 1, 2025)

POPULATION

Total Population 5,493 (100%)
Population in Households 5,493 (100.0%)
Population in Families 4,624 (84.2%)
Population in Group Quarters1 0
Population Density 116
Diversity Index2 26
 
 

INCOME

Median Household Income $100,520
Average Household Income $127,536
% of Income for Mortgage4 33%
Per Capita Income $48,015
Wealth Index5 134
Socioeconomic Status Index6 Moderate (57.4)
 

HOUSING

Total HU (Housing Units) 2,187 (100%)
Owner Occupied HU 1,692 (77.4%)
Renter Occupied HU 376 (17.2%)
Vacant Housing Units 119 ( 5.4%)
Median Home Value $529,442
Average Home Value $601,399
Housing Affordability Index3 71
 

HOUSEHOLDS

Total Households 2,068
Average Household Size 2.66
Family Households 1,473
Average Family Size 3.00
NOTES
  1. Group Quarters - a place where people live or stay in a group living arrangement. Includes college residents halls, nursing facilities, military barracks, and correctional facilities.
  2. 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 races 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.
  3. The Housing Affordability Index base is 100 and represents a balance point where a resident with a median household income can normally qualify to purchase a median price home. Values above 100 indicate increased affordability, while values below 100 indicate decreased affordability.
  4. The % of Income for Mortgage quantifies the percentage of median household income dedicated to mortgage payments on a home priced at the median value (assuming a 30-year mortgage and a 20% down payment).
  5. The Wealth Index is based on a number of indicators of affluence including average household income and average net worth, but it also includes the value of material possessions and resources. It represents the wealth of the area relative to the national level. Values above or below 100 represent above-average wealth or below-average wealth compared to the national level.
  6. The Socioeconomic Index ranges from zero (lowest relative status) to 100 (highest relative status). This measure quantifies disparities in social position of an area's inhabitants and is built from a broad range of demographic, housing, and socioeconomic inputs. More information on this measure can be found in Esri's SEI tutorial.

GROWTH RATE / YEAR

 2020-2025 2025-2030
Population 0.12% 0.55%
Households 0.39% 0.61%
Families   0.36%
Median Household Income   2.50%
Per Capita Income   2.15%
Owner Occupied HU   0.80%

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

The table below compares 21791 to the other 458 ZIP Codes in Maryland by rank and percentile using July 1, 2025 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 # 232 50th
Population Density # 344 25th
Median Household Income # 258 44th
Housing Affordability Index # 109 24th
Per Capita Income # 257 44th
Diversity Index # 390 15th

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


Popular Places Near ZIP Code 21791


Use HTL Address Research for a Maryland Address and get...

Boundary Maps, Demographic Data, School Zones Review maps and data for the neighborhood, city, county, ZIP Code, and school zone. July 1, 2025, data includes home values, household income, percentage of homes owned, rented or vacant, etc.



Quick & Easy Ways to...

  1. Get Current Demographic Data for Cities, Towns, and ZIP Codes
  2. View Boundary Maps, for Cities, Towns, and ZIP Codes
  3. Locate Physical, Cultural, and Historical Features

Maryland Census Data Comparison Tool

Compare Maryland July 1, 2025 Data
Data:
Locations:
Highest or Lowest:
Results:

More Tools and Resources:

  1. For information about schools and school attendance zones, use the HTL Address Tool
  2. Our new HTL Neighborhood Explorer provides lots of detail about any neighborhood.
  3. The new 2-Minute Introduction and Concise Guide to Big Data which will help you make the most effective use of HomeTownLocator Tools.
  4. See the References & Data Sources page for more information about methodology and sources of data.



View ALL 21791 Content

Carroll County


Advertisement



Advertisement
Advertisement

Home | About HTL | Advertise Here | References | Legal | Privacy | Contact
Copyright © 2025 HTL, Inc. All Rights Reserved.
Website Development and Marketing by Blue Tangerine