PlainZIP

Rocky Ridge, MD · standard

ZIP Code 21778

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

1,094
24/sq mi
$76,458
Median income
$382,100
Median home value
27.0%
Bachelor's or higher

The verdict

Rocky Ridge pairs an above-median household income with upper-quartile home values, in a rural, homeowner-dominated area.

Top 43%
household income, US ZIPs
Top 23%
home value, US ZIPs
24
people per sq mi
81%
owner-occupied homes

Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 21778 against every reporting US ZIP.

ZIP code 21778 is a sparsely populated ZIP (a standard USPS delivery area) in Rocky Ridge, Frederick County, Maryland, home to just 1,094 residents across 45.4 square miles, a density of 24 people per square mile, in the New York time zone.

ZIP 21778 lands in the middle-income range, with a median household income of $76,458 (33% below the Maryland average), while per-capita income is $54,798. Poverty here runs at 0.9%, with unemployment measured at 6.5%. The typical home here is valued at $382,100 (15% below the state average); renters pay a median of - monthly, and 81.3% of units are owner-occupied.

Educational attainment sits below the national norm: 27.0% of adults hold a bachelor's degree or higher, the median age is 58.4, and the average commute is -. A geography-based comparison follows: 10 ZIP codes within about 10 miles of 21778, 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 →

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 21778, Rocky Ridge, 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

1,094

Population

45.4

Area (sq mi)

24

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 21778?

58.4

Median Age

38.8%

Male

61.2%

Female

0.0%

Foreign-Born

White 100.0%
African American 0.0%
Asian 0.0%
American Indian or Alaska Native 0.0%
Native Hawaiian or Pacific Islander 0.0%
Two or More Ethnicities 0.0%
Hispanic or Latino 0.0%

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?

$76,458

Median Household Income

-33% vs state

$54,798

Per Capita Income

0.9%

Poverty Rate

6.5%

Unemployment Rate

How ZIP 21778 ranks nationally

Rocky Ridge, MD household income vs. every US ZIP code

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

$76,458 Top 43% higher than 57% 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%). This entry sits in this band. $80,000–$100,000: 5,778 US ZIPs (19%). Above this entry. $100,000–$120,000: 2,855 US ZIPs (9%). Above this entry. $120,000–$140,000: 1,362 US ZIPs (4%). Above this entry. $140,000–$160,000: 686 US ZIPs (2%). Above this entry. $160,000–$180,000: 364 US ZIPs (1%). Above this entry. $180,000–$200,000: 186 US ZIPs (1%). Above this entry. $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 57.5%
Bachelor's Degree or Higher 27.0%

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

What does housing look like?

332

Total Housing Units

332

Occupied Units

0

Vacant Units

2.24

Avg Household Size

Occupancy Type

Owner 81.3%
Renter 18.7%

$382,100

Median Home Value

-15% vs state

1979

Median Year Built

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

What businesses operate in this ZIP?

Census Bureau data shows 16 business establishments in ZIP 21778, employing approximately 125 people with a combined annual payroll of $5,506,000.

16

Businesses

125

Employees

$5.5M

Annual Payroll

1

Industry Sectors

Industry Establishments % of Total
Construction 12 75.0%

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 21778 vs 21727 →

ZIP 21778 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 21778 ranks #9 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 21778 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 21778 ranks #9 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
21727 Emmitsburg, MD 5,850 5.1 mi
21757 Keymar, MD 3,036 4.4 mi
21788 Thurmont, MD 11,622 4.7 mi
21798 Woodsboro, MD 2,345 5.8 mi
21793 Walkersville, MD 9,775 8.6 mi
21780 Sabillasville, MD 1,625 8.1 mi
21762 Libertytown, MD 249 10.5 mi
21791 Union Bridge, MD 5,281 9.5 mi
21702 Frederick, MD 38,847 11.5 mi
17214 Blue Ridge Summit, PA 1,089 11.6 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 Rocky Ridge, MD Maryland

Frequently Asked Questions

What county is ZIP code 21778 in? ▼
ZIP code 21778 (Rocky Ridge) 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 21778? ▼
ZIP code 21778 in Rocky Ridge, MD has a population of 1,094 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 21778? ▼
The median household income in ZIP 21778 is $76,458, which is 0% above the national average of $76,288.
What is the average home value in ZIP 21778? ▼
The median home value in ZIP 21778 is $382,100, which is 37% above the national average of $278,155.
What is the demographic makeup of ZIP 21778? ▼
The largest racial group in ZIP 21778 is White at 100.0%.
How many businesses are in ZIP code 21778? ▼
ZIP code 21778 has 16 business establishments employing approximately 125 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What is the education level in ZIP code 21778? ▼
In ZIP code 21778, 57.5% of residents aged 25+ have a high school diploma or higher, and 27.0% hold a bachelor's degree or higher. These figures come from the Census Bureau ACS 5-Year Estimates (2023).
What percentage of residents own vs. rent in ZIP 21778? ▼
In ZIP code 21778, approximately 81.3% of occupied housing units are owner-occupied and 18.7% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 21778? ▼
The poverty rate in ZIP code 21778 is 0.9% 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.