Mount Airy, MD 21771 ZIP Code Profile


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ZIP Code 21771: Basic Data & USPS Preferred City Name

Preferred Name, USPS
Mount Airy, MD 21771

  • ZIP Code Type: STANDARD
  • Businesses Addresses: 747
  • Single Family Addresses: 10,423
  • Multi-Family Addresses: 106
  • County: Frederick County
  • Centroid: Latitude 39.388, Longitude -77.148
  • Time Zone: Eastern Time Zone (UTC -5 hours)
  • Observes DST: Yes

ZIP Code 21771 has segments in 4 Counties / Independent Cities (Carroll, Frederick, Howard, Montgomery).

Neighborhood Data

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21771 ZIP Code Map

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Mount Airy, MD 21771 Data & Demographics (As of July 1, 2016)


Total Population 30,104
Population in Households 29,927
Population in Familes 27,106
Population in Group Qrtrs 177
Population Density1 380
Diversity Index2 23


Total Households 10,032
Average Household Size 2.98
Family Households 8,237
Average Family Size 3


Total Housing Units 10,384 (100%)
Owner Occupied HU 9,017 (86.8%)
Renter Occupied HU 1,015 ( 9.8%)
Vacant Housing Units 352 ( 3.4%)
Median Home Value $424,439
Average Home Value $452,689


Median Household Income $107,968
Average Household Income $128,987
Per Capita Income $43,199
  (Compound Annual Growth Rates)


2010-2015 2015-2020
Population 0.52% 0.66%
Households 0.52% 0.65%
Families 0.42% 0.59%
Median Household Income   1.35%
Per Capita Income   1.7%
1) Population Density = Total Population per square mile.
2) The Diversity Index is a scale of 0 to 100 that represents the likelyhood 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.
Based on Census 2010 counts, the Diversity Index for the United States was 60.6 and it is expected to increase to 64.8 by July 1, 2018.

Mount Airy, MD 21771 - Peer Comparisons by Rank and Percentile

The table below compares 21771 to the other 455 ZIP Codes in Maryland by rank and percentile using July 1, 2016 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 # 79 83rd
Population Density1 # 232 49th
Diversity Index2 # 339 26th
Median Household Income # 82 82nd
Per Capita Income # 124 73rd

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

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