Keymar, MD · standard
ZIP Code 21757
Frederick County, Maryland - Census ACS demographics, housing tenure, and business patterns, benchmarked against every US ZIP.
- 3,036
- 31/sq mi Moderate-density area
- $100,500
- Median income Above-median income area
- $466,100
- Median home value Above-median home value
- 29.5%
- Bachelor's or higher Near-average bachelor's attainment
National ZIP placement
Keymar pairs an upper-quartile household income with upper-quartile home values, in a rural, homeowner-dominated area.
- Top 19%
- household income, US ZIPs
- Top 15%
- home value, US ZIPs
- 31
- people per sq mi
- 82%
- owner-occupied homes
Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 21757 against every reporting US ZIP.
FHFA HPI release change
What changed in the latest House Price Index year
- FHFA House Price Index values in ZIP 21757 (Keymar, MD) rose +6.2% from 2023 to 2024. The all-transactions index moved from 239.9 in 2023 to 254.7 in 2024 (2000 = 100).
ZIP code 21757 covers 97.6 square miles in Keymar, Frederick County, Maryland (a standard USPS delivery area), with a modest 3,036 residents on file, a density of 31 people per square mile, in the New York time zone.
ZIP 21757 lands in the middle-income range, with a median household income of $100,500 (12% below the average Maryland ZIP), while per-capita income is $46,390. Both reported hardship measures are comparatively low in absolute terms: poverty is 1.7% and unemployment is 3.2%. Median home value is $466,100 (4% above the average Maryland ZIP) and median rent is $1,408; 82.4% of occupied homes are owner-occupied.
Educational attainment sits below the national norm: 29.5% of adults hold a bachelor's degree or higher, the median age is 37.8, and the average commute is 31 minutes. The page also surfaces 7 ZIP codes within roughly 10 miles and 6 more in Frederick County, so 21757 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 →
Top industries in ZIP 21757
Top 5 sectors by establishment count in Keymar, MD
Which industries have the most business establishments in ZIP 21757.
- Construction
Construction
16 establishments
- Other services (except public administration)
Other services (except public administration)
11 establishments
- Transportation and warehousing
Transportation and warehousing
7 establishments
- Professional, scientific, and technical services
Professional, scientific, and technical services
7 establishments
- Retail trade 5
Retail trade
5 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, American Community Survey 5-Year Estimates + ZIP Code Business Patterns + FHFA HPI ACS demographics and median rent, ZBP business establishments, FHFA HPI for ZIP 21757, Keymar, 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
3,036
Population
97.6
Area (sq mi)
31
People / sq mi
New York
Time Zone
standard
ZIP Type
Who lives in ZIP 21757?
37.8
Median Age
55.0%
Male
45.0%
Female
4.3%
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?
$100,500
Median Household Income
-12% vs state ZIP avg
$46,390
Per Capita Income
1.7%
Poverty Rate
3.2%
Unemployment Rate
31.4 min
Mean Commute Time
How ZIP 21757 ranks among Maryland ZIPs
Keymar, 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)
$100,500 46th percentile higher than 46% 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
1,072housing units
1,072
Total Housing Units
1,018
Occupied Units
54
Vacant Units
2.60
Avg Household Size
Occupancy Type
$466,100
Median Home Value
+4% vs state ZIP avg
$1,408
Median Rent
1962
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
+6.2%
YoY Change (2024)
255
HPI Index (2000 = 100)
+155%
Total Change Since 2000
Home values in ZIP 21757 have increased 6.2% over the past year (2024). Since 2000, this ZIP has seen +155% cumulative appreciation.
| Year | Annual Change | HPI Index |
|---|---|---|
| 2020 | +9.9% | 191 |
| 2021 | +3.4% | 198 |
| 2022 | +17.8% | 233 |
| 2023 | +3.0% | 240 |
| 2024 | +6.2% | 255 |
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 64 business establishments in ZIP 21757, employing approximately 457 people with a combined annual payroll of $24,356,000.
64
Businesses
457
Employees
$24.4M
Annual Payroll
8
Industry Sectors
| Industry | Establishments | % of Total |
|---|---|---|
| Construction | 16 | 25.0% |
| Other services (except public administration) | 11 | 17.2% |
| Transportation and warehousing | 7 | 10.9% |
| Professional, scientific, and technical services | 7 | 10.9% |
| Retail trade | 5 | 7.8% |
| Manufacturing | 4 | 6.3% |
| Administrative and support and waste management and remediation services | 4 | 6.3% |
| Wholesale trade | 3 | 4.7% |
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 21757 vs 21778 →
ZIP 21757 vs its nearest neighbors, by population
Resident population of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 21787
Taneytown (21787)
10,693 residents
- 21793
Walkersville (21793)
9,775 residents
- 21727
Emmitsburg (21727)
5,850 residents
- 21791
Union Bridge (21791)
5,281 residents
- 21757 3,036
Keymar (21757)
3,036 residents
- 21798 2,345
Woodsboro (21798)
2,345 residents
- 21778 1,094
Rocky Ridge (21778)
1,094 residents
- 21762 249
Libertytown (21762)
249 residents
What this shows Among its immediate neighbors, ZIP 21757 ranks #5 by population - useful context the national average alone can't give.
ZIP 21757 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
- 21757
Keymar (21757)
$100,500 median income
- 21727
Emmitsburg (21727)
$95,236 median income
- 21791
Union Bridge (21791)
$93,015 median income
- 21787
Taneytown (21787)
$91,682 median income
- 21778
Rocky Ridge (21778)
$76,458 median income
What this shows By household income, ZIP 21757 ranks #3 of 7 neighboring ZIPs, local affluence varies block to block, not just metro to metro.
Nationwide ZIPs with similar ACS profiles
Two Census-derived peer sets for ZIP 21757, 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 (3,036 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 21757 in?
ZIP code 21757 (Keymar) 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 21757?
ZIP code 21757 in Keymar, MD has a population of 3,036 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 21757?
The median household income in ZIP 21757 is $100,500, which is 32% above the national average of $76,288.
What is the average home value in ZIP 21757?
The median home value in ZIP 21757 is $466,100, which is 68% above the national average of $278,155.
What is the demographic makeup of ZIP 21757?
The largest racial group in ZIP 21757 is White at 90.6%. Hispanic or Latino residents make up 2.4% of the population.
How many businesses are in ZIP code 21757?
ZIP code 21757 has 64 business establishments employing approximately 457 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What are the main industries in ZIP code 21757?
The top industries by establishment count in ZIP 21757 are: Construction (16), Other services (except public administration) (11), Transportation and warehousing (7). There are 8 industry sectors represented in total.
How have home values changed in ZIP code 21757?
According to the FHFA House Price Index, home values in ZIP 21757 increased by 6.2% in 2024. Since 2000, home values in this ZIP have appreciated by approximately 155%. 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 21757?
In ZIP code 21757, 67.1% of residents aged 25+ have a high school diploma or higher, and 29.5% 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 21757?
The mean commute time for workers in ZIP code 21757 is 31.4 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 21757?
In ZIP code 21757, approximately 82.4% of occupied housing units are owner-occupied and 17.6% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 21757?
The poverty rate in ZIP code 21757 is 1.7% 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 21757's numbers, next.
- See how ZIP 21757 compares to a neighboring ZIP code on the same Census fields Compare this ZIP
- Check where Keymar, 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.