21057 ZIP Code — Glen Arm, MD

Baltimore County, Maryland

ZIP code 21057 is located in Glen Arm, Maryland, within Baltimore County. It covers approximately 15.89 square miles and serves a population of 4,530 residents. This is a standard ZIP code in the Eastern (ET) timezone, served by area code 410/443.

About ZIP code 21057

The housing stock consists of predominantly single-family detached homes. Most homes were built in the pre-1940, giving the area an established character. Median home value is $576,100. Owner-occupancy is high at 86%, well above the national average.

Median household income is $163,462. 40% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. The average commute of 32 minutes is near the national average.

Educational attainment is high — 55% of residents hold a bachelor's degree or higher, well above the national average of 33%.

Overall, ZIP code 21057 reflects a community defined by a highly educated population, high homeownership, and a significant Social Security-dependent population.

4,530

population

15.89

sq mi land

Standard

ZIP type

Eastern (ET)

timezone

21057 ZIP code map

Cities in ZIP code 21057

Below are the cities the US Postal Service accepts for ZIP code 21057. Using any city not on this list may result in mail delivery delays.

City	Status
Glen Arm	Preferred

Nearby ZIP codes

21082 Hydes (2.5 mi) 21051 Fork (3.3 mi) 21236 Nottingham (4.1 mi) 21234 Parkville (4.2 mi) 21128 Perry Hall (4.2 mi) 21286 Towson (4.4 mi) 21087 Kingsville (4.4 mi) 21013 Baldwin (4.8 mi) 21131 Phoenix (5.2 mi) 21156 Upper Falls (6 mi) 21047 Fallston (6.7 mi) 21162 White Marsh (6.8 mi)

Demographics updated 05/2026

Population
Total population	4,530
Population density	285 / sq mi
State FIPS	24
County FIPS	005

Geography
Land area	15.89 sq mi
Water area	0.44 sq mi
Latitude	39.4483
Longitude	-76.5013
Timezone	Eastern (ET)
Area code	410/443

Total population by age

Gender

Race & ethnicity

Economics updated 05/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	22.4%	31.4%	28.2%
$50k – $100k	14.5%	30.7%	28.2%
$100k – $200k	36.1%	28.5%	30.1%
Over $200k	27.0%	9.5%	13.4%

Demographics & statistics

4,530

Population

285

People per sq mi

45.5

Median age

$163,462

Median household income

$62,251

Per capita income

$576,100

Median home value

$1,620

Median monthly rent

86.0%

Home ownership

1.4%

Poverty rate

1.9%

Unemployment

1,497

Housing units

54.7%

Bachelor's or higher

Age distribution

Male Female

135

Under 5

129

184

5–9

175

150

10–14

144

15–19

137

20–24

25–34

348

35–44

332

298

45–54

285

220

55–59

210

170

60–64

163

239

65–74

228

197

75–84

188

85+

← Male

Female →

Age summary

Group	Count	%
Under 18	1,110	24.5%
18 and over	3,420	75.5%
65 and over	961	21.2%
Median age	45.5 years

Race & ethnicity

White 85.9%

Black or African American 4.5%

Hispanic or Latino 3%

Two or more races 3%

Asian 2.1%

Other race 1.2%

American Indian / Alaska Native 0.2%

Group	Count	%
White	4,011	85.9%
Black or African American	212	4.5%
Hispanic or Latino	142	3%
Two or more races	141	3%
Asian	99	2.1%
Other race	58	1.2%
American Indian / Alaska Native	9	0.2%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	22.4%	31.4%	28.2%
$50k – $100k	14.5%	30.7%	28.2%
$100k – $200k	36.1%	28.5%	30.1%
Over $200k	27.0%	9.5%	13.4%

Under $10k 2.8%

$10k–$15k 2.7%

$15k–$25k 3.7%

$25k–$35k 3.2%

$35k–$50k 7.2%

$50k–$75k 2.2%

$75k–$100k 4.7%

$100k–$150k 20.7%

$150k–$200k 17.5%

$200k+ 35.3%

Range	% of households
Under $10k	2.8%
$10k–$15k	2.7%
$15k–$25k	3.7%
$25k–$35k	3.2%
$35k–$50k	7.2%
$50k–$75k	2.2%
$75k–$100k	4.7%
$100k–$150k	20.7%
$150k–$200k	17.5%
$200k+	35.3%
Median income	$163,462

Housing

Home values

Under $50k 1.4%

$150k–$200k 2.2%

$200k–$300k 2.3%

$300k–$500k 27.2%

$500k–$1M 63.3%

$1M+ 3.6%

Housing overview

Metric	Value
Median home value	$576,100
Median rent / month	$1,620
Owner occupied	86.0%
Renter occupied	14.0%
Vacant	6.8%
Single-family detached	86.5%
Large apartment buildings	6.2%
Mobile homes	0.0%
Median rooms	8.1
Avg household size (owned)	3.04

Year built

Era	%
2020 or later	0.0%
2010–2019	7.2%
2000–2009	1.6%
1990–1999	7.3%
1980–1989	17.3%
1970–1979	19.3%
1960–1969	11.7%
1950–1959	13.3%
1940–1949	2.3%
1939 or earlier	19.9%

Bedrooms

Size	% of units
No bedroom (studio)	2.6%
1 bedroom	5.6%
2 bedrooms	6.9%
3 bedrooms	26.3%
4 bedrooms	44.2%
5+ bedrooms	14.5%

Vehicles per household

Vehicles	% of households
No vehicle	7.0%
1 vehicle	11.2%
2 vehicles	49.8%
3 or more	32.0%

Heating fuel

Fuel type	%
Utility gas	14.1%
Electricity	31.7%
Propane / LP gas	5.2%
Fuel oil	38.2%
Wood	5.5%
No fuel used	2.7%

Households & families

Household type	Count	%
Married-couple family	1,207	75.2%
Cohabiting couple	14	0.9%
Male householder, no spouse	145	9.0%
Female householder, no spouse	238	14.8%
Households with children under 18	596	37.2%
Households with seniors (65+)	644	40.1%
Average household size	2.80

Marital status

Status	Male	Female
Never married	21.4%	14.7%
Married	72.0%	70.3%
Separated	1.4%	0.4%
Widowed	1.9%	8.2%
Divorced	3.3%	6.4%

Education

Less than 9th grade 1.9%

Some HS, no diploma 5.1%

HS graduate 12.4%

Some college, no degree 14.9%

Associate's degree 10.9%

Bachelor's degree 30.0%

Graduate / professional 24.7%

Metric	%
HS diploma or higher	93.0%
Bachelor's or higher	54.7%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	159	13.1%
Kindergarten	77	6.3%
Elementary school	365	30.1%
High school	352	29.0%
College / grad school	261	21.5%

Employment

Industry of employment

Education & healthcare 23.2%

Finance & real estate 17.7%

Professional & management 13.4%

Construction 8.7%

Public administration 8.5%

Other services 5.0%

Retail trade 4.7%

Transportation & utilities 4.1%

Manufacturing 3.9%

Information 3.4%

Arts, food & hospitality 3.1%

Agriculture & mining 2.7%

Wholesale trade 1.6%

Occupation

Category	%
Management, business & arts	59.1%
Service	9.8%
Sales & office	17.6%
Natural resources & construction	11.6%
Production & transportation	1.9%

Employment type

Type	%
Private sector	77.5%
Government	16.4%
Self-employed	5.8%
Unpaid family workers	0.3%

Commute

Method	%
Drive alone	79.4%
Carpool	3.9%
Public transit	0.4%
Walk	0.3%
Work from home	16.0%
Other means	0.0%
Avg commute (minutes)	32.0

Poverty

All people 1.4%

Under 18 years 0.0%

18 and over 1.9%

Married-couple families 0.0%

Female-led households 0.0%

Income support

Source	% of households
Social Security	39.5%
Retirement income	28.9%
Supplemental Security	1.2%
Cash public assistance	0.0%
Food stamps / SNAP	1.5%

Health indicators

Condition	%
Obesity	26.3%
High blood pressure	36.0%
High cholesterol	37.9%
Diabetes	8.8%
Heart disease	6.8%
Stroke	2.9%
Asthma	8.7%
Arthritis	28.9%
Kidney disease	3.0%
Pulmonary disease	5.4%
Cancer	9.9%

Behavior / access	%
Smoking	10.0%
Binge drinking	13.7%
No physical activity	18.2%
Less than 7 hrs sleep	27.2%
Depression	17.4%
Fair or poor health	10.1%
Poor mental health	11.6%
Poor physical health	7.6%
No health insurance	6.6%
Visited doctor (checkup)	79.0%
Visited dentist	74.5%
Cholesterol screening	95.3%
Teeth loss	6.9%

Veterans & disability

Veterans	Count	%
Civilian veterans	114	3.3%

Disability	%
Any disability	10.7%
Under 18	7.2%
18–64 years	5.3%
65 and over	28.5%

Health insurance coverage

Type	%
Private insurance	88.8%
Public insurance	22.5%
No insurance	3.5%
Uninsured under 19	6.1%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	4,266	94.2%
Spanish	83	1.9%
Other Indo-European	0	0.0%
Asian & Pacific Islander	62	1.5%
Other languages	1	0.0%

Place of birth & citizenship

Origin	Count	%
Native born (US)	4,261	94.1%
Born in same state	4,166	92.0%
Born in different state	3,059	67.5%
Foreign born	95	2.1%
Naturalized citizen	269	5.9%
Not a US citizen	262	97.4%

Ancestry

Ancestry	Count	%
Italian	618	13.6%
French	577	12.7%
Arab	343	7.6%

Ancestry	Count	%
German	92	2%
Polish	41	0.9%
Norwegian	11	0.2%

Technology access

Metric	% of households
Computer access	35.4%
Internet access	93.5%

Source: U.S. Census Bureau, American Community Survey 2025 estimates.

Frequently asked questions about ZIP code 21057

What city is ZIP code 21057 in?

ZIP code 21057 is primarily assigned to Glen Arm, Maryland.

What county is ZIP code 21057 in?

ZIP code 21057 falls within Baltimore County, Maryland.

How educated is the population of ZIP code 21057?

55% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.

Is ZIP code 21057 mostly owner-occupied?

86% of occupied units in ZIP code 21057 are owner-occupied, well above the national average.

Does ZIP code 21057 have a large retiree population?

40% of households in ZIP code 21057 receive Social Security income, suggesting a significant retiree or disability population.

What is the median household income in ZIP code 21057?

The median household income in ZIP code 21057 is $163,462, above the national median of ~$75,000.

What timezone is ZIP code 21057 in?

ZIP code 21057 observes the EST timezone.