ZIP Code 21157
standardSource:
Westminster · Carroll County · Maryland
- Population
- 36,920
- Median income
- $104,966
- Median home value
- $424,100
- Bachelor's or higher
- 37.9%
- Land area
- 198.6 sq mi
186/sq mi
▲ 38% vs US
higher than 84% of US ZIPs
▲ 52% vs US
higher than 82% of US ZIPs
Median age 43.2
New York
ZIP code 21157 in Westminster, Maryland has a population of 36,920. The median household income is $104,966, which is 38% above the national average. Median home value is $424,100, 52% above the US average. 37.9% of residents hold a bachelor's degree or higher.
ZIP code 21157 is classified by USPS as a standard delivery area and covers roughly 198.6 square miles in Westminster, Carroll County, Maryland. The area is home to 36,920 residents, producing a population density of 186 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 21157 against Maryland and the nation.
On the economic side, the median household income for ZIP 21157 sits at $104,966 (8% below the Maryland average), while per-capita income is $49,793. The poverty rate stands at 6.7% and the unemployment rate at 4.1%. On housing, the median home value is $424,100 (5% below the state average) with median rent at $1,331 per month, and 76.8% of occupied units are owner-occupied, a direct signal of whether 21157 behaves more like a homeowner neighborhood or a renter-heavy ZIP.
Education and household profile round out the picture: 37.9% of adults hold a bachelor's degree or higher, the median age is 43.2, and the average commute is 31 minutes. We also surface 6 nearby ZIP codes within roughly 10 miles and 6 additional ZIPs sharing Carroll County, so you can benchmark 21157 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 21157
Top 5 sectors by establishment count
Which industries have the most business establishments in ZIP 21157.
- Health care and social assistance
Health care and social assistance
210 establishments
- Retail trade
Retail trade
161 establishments
- Other services (except public administration)
Other services (except public administration)
156 establishments
- Professional, scientific, and technical services
Professional, scientific, and technical services
153 establishments
- Construction
Construction
150 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 21157, Westminster, 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
36,920
Population
198.6
Area (sq mi)
186
People / sq mi
New York
Time Zone
standard
ZIP Type
Who lives in ZIP 21157?
43.2
Median Age
48.1%
Male
51.9%
Female
5.9%
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?
$104,966
Median Household Income
-8% vs state
$49,793
Per Capita Income
6.7%
Poverty Rate
4.1%
Unemployment Rate
31.0 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?
15,471
Total Housing Units
14,785
Occupied Units
686
Vacant Units
2.48
Avg Household Size
Occupancy Type
$424,100
Median Home Value
-5% vs state
$1,331
Median Rent
1978
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
+8.9%
YoY Change (2024)
255
HPI Index (2000 = 100)
+155%
Total Change Since 2000
Home values in ZIP 21157 have increased 8.9% over the past year (2024). Since 2000, this ZIP has seen +155% cumulative appreciation.
| Year | Annual Change | HPI Index |
|---|---|---|
| 2020 | +2.7% | 180 |
| 2021 | +11.0% | 200 |
| 2022 | +9.9% | 220 |
| 2023 | +6.5% | 234 |
| 2024 | +8.9% | 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 1,303 business establishments in ZIP 21157, employing approximately 20,132 people with a combined annual payroll of $1,064,700,000.
1,303
Businesses
20,132
Employees
$1.1B
Annual Payroll
17
Industry Sectors
| Industry | Establishments | % of Total |
|---|---|---|
| Health care and social assistance | 210 | 16.1% |
| Retail trade | 161 | 12.4% |
| Other services (except public administration) | 156 | 12.0% |
| Professional, scientific, and technical services | 153 | 11.7% |
| Construction | 150 | 11.5% |
| Accommodation and food services | 92 | 7.1% |
| Administrative and support and waste management and remediation services | 71 | 5.5% |
| Finance and insurance | 62 | 4.8% |
| Real estate and rental and leasing | 57 | 4.4% |
| Wholesale trade | 48 | 3.7% |
| Manufacturing | 41 | 3.1% |
| Transportation and warehousing | 37 | 2.8% |
| Information | 23 | 1.8% |
| Educational services | 20 | 1.5% |
| Arts, entertainment, and recreation | 12 | 0.9% |
| Management of companies and enterprises | 6 | 0.5% |
| Agriculture, forestry, fishing and hunting | 3 | 0.2% |
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 21157 vs 21048 →
More ZIP Codes in Carroll County
Related Areas
Frequently Asked Questions
What county is ZIP code 21157 in? ▼
What is the population of ZIP code 21157? ▼
What is the median household income in ZIP 21157? ▼
What is the average home value in ZIP 21157? ▼
What is the demographic makeup of ZIP 21157? ▼
How many businesses are in ZIP code 21157? ▼
What are the main industries in ZIP code 21157? ▼
How have home values changed in ZIP code 21157? ▼
What is the education level in ZIP code 21157? ▼
What is the average commute time in ZIP 21157? ▼
What percentage of residents own vs. rent in ZIP 21157? ▼
What is the poverty rate in ZIP code 21157? ▼
ZIP Code Research Guides
Official Data Resources for Westminster, 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.