ZIP Code 21057
standardSource:
Glen Arm · Baltimore County · Maryland
- Population
- 4,112
- Median income
- $145,924
- Median home value
- $623,200
- Bachelor's or higher
- 54.0%
- Land area
- 43.5 sq mi
95/sq mi
▲ 91% vs US
higher than 96% of US ZIPs
▲ 124% vs US
higher than 92% of US ZIPs
Median age 41.3
New York
ZIP code 21057 in Glen Arm, Maryland has a population of 4,112. The median household income is $145,924, which is 91% above the national average. Median home value is $623,200, 124% above the US average. 54.0% of residents hold a bachelor's degree or higher.
ZIP code 21057 is classified by USPS as a standard delivery area and covers roughly 43.5 square miles in Glen Arm, Baltimore County, Maryland. The area is home to 4,112 residents, producing a population density of 95 people per square mile, and falls within the New York time zone. These USPS and Census boundary values drive every downstream statistic on this page, including the benchmarks that compare 21057 against Maryland and the nation.
On the economic side, the median household income for ZIP 21057 sits at $145,924 (28% above the Maryland average), while per-capita income is $61,920. The poverty rate stands at 3.1% and the unemployment rate at 1.7%. On housing, the median home value is $623,200 (39% above the state average) with median rent at $1,746 per month, and 85.1% of occupied units are owner-occupied, a direct signal of whether 21057 behaves more like a homeowner neighborhood or a renter-heavy ZIP.
Education and household profile round out the picture: 54.0% of adults hold a bachelor's degree or higher, the median age is 41.3, and the average commute is 33 minutes. We also surface 10 nearby ZIP codes within roughly 10 miles and 6 additional ZIPs sharing Baltimore County, so you can benchmark 21057 against its immediate geography rather than a national average alone. Every figure is sourced from the U.S. Census Bureau American Community Survey 5-Year Estimates, HUD Fair Market Rents, and FHFA Home Price Index data, no estimates, no proprietary scoring. Verify with HUD →
Top industries in ZIP 21057
Top 5 sectors by establishment count
Which industries have the most business establishments in ZIP 21057.
- Construction
Construction
29 establishments
- Professional, scientific, and technical services
Professional, scientific, and technical services
14 establishments
- Other services (except public administration)
Other services (except public administration)
12 establishments
- Administrative and support and waste management and remediation services 8
Administrative and support and waste management and remediation services
8 establishments
- Retail trade 7
Retail trade
7 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 + HUD FMR + FHFA HPI ACS demographics, ZBP business establishments, HUD Fair Market Rents, FHFA HPI for ZIP 21057, Glen Arm, MD · 2023 Census ACS 5-Year Estimates use a rolling 60-month sample for stable small-geography estimates; ZBP updated annually; HUD FMR + FHFA HPI updated quarterly/annually.
Quick Facts
4,112
Population
43.5
Area (sq mi)
95
People / sq mi
New York
Time Zone
standard
ZIP Type
Who lives in ZIP 21057?
41.3
Median Age
49.5%
Male
50.5%
Female
4.1%
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?
$145,924
Median Household Income
+28% vs state
$61,920
Per Capita Income
3.1%
Poverty Rate
1.7%
Unemployment Rate
32.7 min
Mean Commute Time
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?
1,603
Total Housing Units
1,545
Occupied Units
58
Vacant Units
2.82
Avg Household Size
Occupancy Type
$623,200
Median Home Value
+39% vs state
$1,746
Median Rent
1970
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
-0.3%
YoY Change (2024)
209
HPI Index (2000 = 100)
+109%
Total Change Since 2000
Home values in ZIP 21057 have decreased 0.3% over the past year (2024). Since 2000, this ZIP has seen +109% cumulative appreciation.
| Year | Annual Change | HPI Index |
|---|---|---|
| 2020 | +2.1% | 163 |
| 2021 | +5.0% | 171 |
| 2022 | +14.6% | 196 |
| 2023 | +6.9% | 210 |
| 2024 | -0.3% | 209 |
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 110 business establishments in ZIP 21057, employing approximately 879 people with a combined annual payroll of $51,451,000.
110
Businesses
879
Employees
$51.5M
Annual Payroll
12
Industry Sectors
| Industry | Establishments | % of Total |
|---|---|---|
| Construction | 29 | 26.4% |
| Professional, scientific, and technical services | 14 | 12.7% |
| Other services (except public administration) | 12 | 10.9% |
| Administrative and support and waste management and remediation services | 8 | 7.3% |
| Retail trade | 7 | 6.4% |
| Wholesale trade | 6 | 5.5% |
| Finance and insurance | 6 | 5.5% |
| Real estate and rental and leasing | 5 | 4.5% |
| Health care and social assistance | 5 | 4.5% |
| Arts, entertainment, and recreation | 5 | 4.5% |
| Manufacturing | 3 | 2.7% |
| Accommodation and food services | 3 | 2.7% |
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 21057 vs 21082 →
| ZIP Code | City | Population | Distance |
|---|---|---|---|
| 21082 | Hydes, MD | 654 | 2.5 mi |
| 21051 | Fork, MD | 279 | 3.2 mi |
| 21013 | Baldwin, MD | 4,653 | 4.2 mi |
| 21236 | Nottingham, MD | 38,474 | 4.4 mi |
| 21234 | Parkville, MD | 69,752 | 4.2 mi |
| 21087 | Kingsville, MD | 5,451 | 4.8 mi |
| 21128 | Perry Hall, MD | 12,802 | 4.4 mi |
| 21286 | Towson, MD | 19,206 | 4.4 mi |
| 21131 | Phoenix, MD | 7,253 | 5.2 mi |
| 21237 | Rosedale, MD | 30,059 | 7.7 mi |
More ZIP Codes in Baltimore County
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Frequently Asked Questions
What county is ZIP code 21057 in? ▼
What is the population of ZIP code 21057? ▼
What is the median household income in ZIP 21057? ▼
What is the average home value in ZIP 21057? ▼
What is the demographic makeup of ZIP 21057? ▼
How many businesses are in ZIP code 21057? ▼
What are the main industries in ZIP code 21057? ▼
How have home values changed in ZIP code 21057? ▼
What is the education level in ZIP code 21057? ▼
What is the average commute time in ZIP 21057? ▼
What percentage of residents own vs. rent in ZIP 21057? ▼
What is the poverty rate in ZIP code 21057? ▼
ZIP Code Research Guides
Official Data Resources for Glen Arm, MD
Verify and explore additional data for this area using these official government sources.
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023). Business data: Source: Census ZIP Code Business Patterns (ZBP) 2023. Home value trends: Source: FHFA House Price Index (HPI), Five-Digit ZIP Codes.
PlainZIP is not affiliated with the U.S. Census Bureau or any government agency.
Read our methodology , how this data is sourced, computed, and verified.