PlainZIP

Monrovia, MD · standard

ZIP Code 21770

Frederick County, Maryland - Census ACS demographics, housing tenure, and business patterns, benchmarked against every US ZIP.

5,164
181/sq mi
$183,571
Median income
$632,500
Median home value
54.8%
Bachelor's or higher

The verdict

Monrovia pairs a top-decile household income with top-decile home values, in a rural, homeowner-dominated area.

Top 2%
household income, US ZIPs
Top 8%
home value, US ZIPs
181
people per sq mi
99%
owner-occupied homes

Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 21770 against every reporting US ZIP.

ZIP code 21770 is a mid-sized community (a standard USPS delivery area) in Monrovia, Frederick County, Maryland, home to 5,164 residents across 28.6 square miles, a density of 181 people per square mile, in the New York time zone.

ZIP 21770 skews affluent, with a median household income of $183,571 (61% above the Maryland average), while per-capita income is $58,954. Local economic indicators show a 1.5% poverty rate alongside 2.7% unemployment. The typical home here is valued at $632,500 (41% above the state average); renters pay a median of - monthly, and 98.8% of units are owner-occupied.

This is a highly-educated ZIP: 54.8% of adults hold a bachelor's degree or higher, the median age is 39.8, and the average commute is 35 minutes. A geography-based comparison follows: 10 ZIP codes within about 10 miles of 21770, plus 6 more within Frederick County, give a clearer read than the national average alone.

Every figure on this page is sourced from the U.S. Census Bureau American Community Survey 5-Year Estimates (including median rent) and the FHFA House Price Index, no estimates, no proprietary scoring. Verify with Census →

Top industries in ZIP 21770

Top 5 sectors by establishment count in Monrovia, MD

Which industries have the most business establishments in ZIP 21770.

establishments

What this shows Establishment counts come from the Census ZIP Code Business Patterns program, which counts physical business locations rather than employees or revenue.

Source U.S. Census Bureau · ZIP Code Business Patterns (ZBP) As of 2023

Source: U.S. Census Bureau, American Community Survey 5-Year Estimates + ZIP Code Business Patterns + FHFA HPI ACS demographics and median rent, ZBP business establishments, FHFA HPI for ZIP 21770, Monrovia, MD · 2023 Census ACS 5-Year Estimates use a rolling 60-month sample for stable small-geography estimates; ZBP updated annually; FHFA HPI updated quarterly/annually.

Quick Facts

5,164

Population

28.6

Area (sq mi)

181

People / sq mi

New York

Time Zone

standard

ZIP Type

Neighborhood Scorecard
Get an A-F grade across income, safety, housing, rent, education, commute, and childcare for this ZIP code.
View Scorecard →

Who lives in ZIP 21770?

39.8

Median Age

49.0%

Male

51.0%

Female

13.1%

Foreign-Born

White 72.4%
African American 7.9%
Asian 12.3%
American Indian or Alaska Native 0.0%
Native Hawaiian or Pacific Islander 0.0%
Two or More Ethnicities 6.6%
Hispanic or Latino 3.1%

Hispanic or Latino is an ethnicity category from the Census Bureau and may overlap with other categories above.

Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)

How much do residents earn?

$183,571

Median Household Income

+61% vs state

$58,954

Per Capita Income

1.5%

Poverty Rate

2.7%

Unemployment Rate

35.2 min

Mean Commute Time

How ZIP 21770 ranks nationally

Monrovia, MD household income vs. every US ZIP code

Median household income, the full national distribution, with this ZIP marked

$183,571 Top 2% higher than 98% of 30,318 US ZIPs

$0–$20,000: 118 US ZIPs (0%). Below this entry. $20,000–$40,000: 1,573 US ZIPs (5%). Below this entry. $40,000–$60,000: 7,092 US ZIPs (23%). Below this entry. $60,000–$80,000: 9,980 US ZIPs (33%). Below this entry. $80,000–$100,000: 5,778 US ZIPs (19%). Below this entry. $100,000–$120,000: 2,855 US ZIPs (9%). Below this entry. $120,000–$140,000: 1,362 US ZIPs (4%). Below this entry. $140,000–$160,000: 686 US ZIPs (2%). Below this entry. $160,000–$180,000: 364 US ZIPs (1%). Below this entry. $180,000–$200,000: 186 US ZIPs (1%). This entry sits in this band. $200,000–$220,000: 324 US ZIPs (1%). Above this entry. This ZIP $0 $200K+ every reporting US ZIP, bucketed by value

Each bar is a $20K-wide band; taller bars hold more US ZIPs. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source U.S. Census Bureau, ACS 5-Year Estimates · 2019–2023

Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)

What is the education profile here?

High School Graduate or Higher 70.5%
Bachelor's Degree or Higher 54.8%

Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)

What does housing look like?

2,632

Total Housing Units

2,622

Occupied Units

10

Vacant Units

3.34

Avg Household Size

Occupancy Type

Owner 98.8%
Renter 1.2%

$632,500

Median Home Value

+41% vs state

1988

Median Year Built

Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)

How have home values changed over time?

FHFA House Price Index, annual appreciation data based on repeat sales and appraisals

+0.2%

YoY Change (2024)

240

HPI Index (2000 = 100)

+140%

Total Change Since 2000

Home values in ZIP 21770 have increased 0.2% over the past year (2024). Since 2000, this ZIP has seen +140% cumulative appreciation.

Year Annual Change HPI Index
2020 +1.1% 184
2021 +11.2% 204
2022 +13.1% 231
2023 +3.8% 240
2024 +0.2% 240

Source: Federal Housing Finance Agency (FHFA) House Price Index, All-Transactions, Five-Digit ZIP Codes (Developmental Index). Index base = 100 in year 2000. Data through 2024. ZIP codes with few transactions may show missing values.

What businesses operate in this ZIP?

Census Bureau data shows 150 business establishments in ZIP 21770, employing approximately 1,461 people with a combined annual payroll of $82,141,000.

150

Businesses

1,461

Employees

$82.1M

Annual Payroll

13

Industry Sectors

Industry Establishments % of Total
Construction 40 26.7%
Professional, scientific, and technical services 34 22.7%
Retail trade 10 6.7%
Administrative and support and waste management and remediation services 10 6.7%
Health care and social assistance 10 6.7%
Other services (except public administration) 10 6.7%
Transportation and warehousing 6 4.0%
Real estate and rental and leasing 6 4.0%
Accommodation and food services 6 4.0%
Information 5 3.3%
Wholesale trade 4 2.7%
Manufacturing 3 2.0%
Educational services 3 2.0%

Source: U.S. Census Bureau, ZIP Code Business Patterns (ZBP), 2023. Employment figures may include noise for disclosure avoidance.

Nearby ZIP Codes

Want a side-by-side? Compare 21770 vs 21754 →

ZIP 21770 vs its nearest neighbors, by population

Resident population of this ZIP and the closest reporting ZIP codes within ~10 miles.

residents

What this shows Among its immediate neighbors, ZIP 21770 ranks #0 by population - useful context the national average alone can't give.

Source U.S. Census Bureau · ACS 5-Year Estimates As of 2019–2023

ZIP 21770 vs its nearest neighbors, by median income

Median household income of this ZIP and the closest reporting ZIP codes within ~10 miles.

median income

What this shows By household income, ZIP 21770 ranks the highest of 9 neighboring ZIPs, local affluence varies block to block, not just metro to metro.

Source U.S. Census Bureau · ACS 5-Year Estimates As of 2019–2023
ZIP Code City Population Distance
21754 Ijamsville, MD 6,323 3.2 mi
21774 New Market, MD 11,662 4.1 mi
20872 Damascus, MD 13,104 4.7 mi
20871 Clarksburg, MD 13,130 6.4 mi
21704 Frederick, MD 13,321 6.3 mi
21762 Libertytown, MD 249 8.9 mi
21771 Mount Airy, MD 29,563 6.1 mi
20876 Germantown, MD 25,496 10.0 mi
21701 Frederick, MD 35,293 7.7 mi
21793 Walkersville, MD 9,775 10.7 mi

More ZIP Codes in Frederick County

21702 standard
Frederick, MD
Pop: 38,847
21701 standard
Frederick, MD
Pop: 35,293
21703 standard
Frederick, MD
Pop: 32,854
21771 standard
Mount Airy, MD
Pop: 29,563
21704 standard
Frederick, MD
Pop: 13,321
21774 standard
New Market, MD
Pop: 11,662

Related Areas

Frederick County Monrovia, MD Maryland

Frequently Asked Questions

What county is ZIP code 21770 in? ▼
ZIP code 21770 (Monrovia) is located in Frederick County, Maryland. Frederick County contains multiple ZIP codes, see the full list at /counties/frederick-md.
What is the population of ZIP code 21770? ▼
ZIP code 21770 in Monrovia, MD has a population of 5,164 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 21770? ▼
The median household income in ZIP 21770 is $183,571, which is 141% above the national average of $76,288.
What is the average home value in ZIP 21770? ▼
The median home value in ZIP 21770 is $632,500, which is 127% above the national average of $278,155.
What is the demographic makeup of ZIP 21770? ▼
The largest racial group in ZIP 21770 is White at 72.4%. Hispanic or Latino residents make up 3.1% of the population.
How many businesses are in ZIP code 21770? ▼
ZIP code 21770 has 150 business establishments employing approximately 1,461 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What are the main industries in ZIP code 21770? ▼
The top industries by establishment count in ZIP 21770 are: Construction (40), Professional, scientific, and technical services (34), Retail trade (10). There are 13 industry sectors represented in total.
How have home values changed in ZIP code 21770? ▼
According to the FHFA House Price Index, home values in ZIP 21770 increased by 0.2% in 2024. Since 2000, home values in this ZIP have appreciated by approximately 140%. This is a developmental index based on repeat sales and appraisal data from Fannie Mae and Freddie Mac.
What is the education level in ZIP code 21770? ▼
In ZIP code 21770, 70.5% of residents aged 25+ have a high school diploma or higher, and 54.8% hold a bachelor's degree or higher. These figures come from the Census Bureau ACS 5-Year Estimates (2023).
What is the average commute time in ZIP 21770? ▼
The mean commute time for workers in ZIP code 21770 is 35.2 minutes according to Census ACS data. The national average is roughly 26 minutes, so commuters here spend more time traveling to work than typical.
What percentage of residents own vs. rent in ZIP 21770? ▼
In ZIP code 21770, approximately 98.8% of occupied housing units are owner-occupied and 1.2% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 21770? ▼
The poverty rate in ZIP code 21770 is 1.5% according to Census Bureau ACS 2023 estimates. This measures the percentage of the population living below the federal poverty threshold.

Read our methodology to see how this data is sourced, computed, and verified.