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 Moderate-density area
- $76,458
- Median income Near-median income area
- $382,100
- Median home value Above-median home value
- 27.0%
- Bachelor's or higher Near-average bachelor's attainment
National ZIP placement
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 average Maryland ZIP), while per-capita income is $54,798. The poverty rate is 0.9%, with unemployment at 6.5%; those measures add context to the income figure. Median home value is $382,100 (15% below the average Maryland ZIP); 81.3% of occupied homes 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 -. The page also surfaces 10 ZIP codes within roughly 10 miles and 6 more in Frederick County, so 21778 can be compared with both its immediate and county-level context.
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
Who lives in ZIP 21778?
58.4
Median Age
38.8%
Male
61.2%
Female
0.0%
Foreign-Born
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 ZIP avg
$54,798
Per Capita Income
0.9%
Poverty Rate
6.5%
Unemployment Rate
How ZIP 21778 ranks among Maryland ZIPs
Rocky Ridge, MD household income vs. every Maryland ZIP code
Median household income among 419 reporting Maryland ZIPs (this ZIP's population is too small for a reliable national-corpus placement)
$76,458 19th percentile higher than 19% of 419 Maryland ZIPs
Each bar is a $20K-wide band; taller bars hold more Maryland 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?
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What does housing look like?
Housing stock: occupied vs vacant
332housing units
332
Total Housing Units
332
Occupied Units
0
Vacant Units
2.24
Avg Household Size
Occupancy Type
$382,100
Median Home Value
-15% vs state ZIP avg
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.
- 21702
Frederick (21702)
38,847 residents
- 21788 11,622
Thurmont (21788)
11,622 residents
- 21793 9,775
Walkersville (21793)
9,775 residents
- 21727 5,850
Emmitsburg (21727)
5,850 residents
- 21791 5,281
Union Bridge (21791)
5,281 residents
- 21757 3,036
Keymar (21757)
3,036 residents
- 21798 2,345
Woodsboro (21798)
2,345 residents
- 21780 1,625
Sabillasville (21780)
1,625 residents
- 21778 1,094
Rocky Ridge (21778)
1,094 residents
What this shows Among its immediate neighbors, ZIP 21778 ranks #9 by population - useful context the national average alone can't give.
ZIP 21778 vs its nearest neighbors, by median income
Median household income of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 21793
Walkersville (21793)
$121,971 median income
- 21798
Woodsboro (21798)
$116,607 median income
- 21702
Frederick (21702)
$106,983 median income
- 21757
Keymar (21757)
$100,500 median income
- 21788
Thurmont (21788)
$98,856 median income
- 21727
Emmitsburg (21727)
$95,236 median income
- 21791
Union Bridge (21791)
$93,015 median income
- 21780
Sabillasville (21780)
$83,785 median income
- 21778
Rocky Ridge (21778)
$76,458 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.
| 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 |
Nationwide ZIPs with similar ACS profiles
Two Census-derived peer sets for ZIP 21778, both outside MD so the neighborhoods are not geographic containment (Nearby and same-county blocks stay local).
Similar population
Nearest cross-state ZIPs by resident population (1,094 here; floor ≥1,000).
Similar median household income
Nearest cross-state ZIPs by ACS median household income.
More ZIP Codes in Frederick County
Related Areas
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.
Related
Take this with you
What to do with ZIP 21778's numbers, next.
- See how ZIP 21778 compares to a neighboring ZIP code on the same Census fields Compare this ZIP
- Check where Rocky Ridge, MD ranks among every U.S. ZIP code on income, education, or homeownership View national rankings
- Save this ZIP to your shortlist to track alongside others you're considering View your shortlist
ZIP Code Tabulation Areas (ZCTAs) are Census Bureau approximations of USPS ZIP codes; figures describe the ZCTA area, not any single address within it.