21231 ZIP Code — Baltimore, MD

Baltimore City County, Maryland

ZIP code 21231 is located in Baltimore, Maryland, within Baltimore City County. It covers approximately 0.87 square miles and serves a population of 14,780 residents. This is a standard ZIP code in the Eastern (ET) timezone, served by area code 410/443/667.

About ZIP code 21231

The housing stock consists of a significant share of large multi-unit buildings. Most homes were built in the pre-1940, giving the area an established character. Median home value is $330,600. Renters make up the majority at 65%, typical of denser urban areas.

The gap between median ($88,091) and mean household income suggests income inequality — a small number of higher earners pull the average up. Poverty affects 19% of residents, above the national average.

The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. The average commute of 26 minutes is near the national average. Remote work is prevalent — 23% of workers work from home.

Educational attainment is high — 66% of residents hold a bachelor's degree or higher, well above the national average of 33%.

Overall, ZIP code 21231 reflects a community defined by a highly educated population, economic challenges above the national average, and a high rate of remote workers.

14,780

population

0.87

sq mi land

Standard

ZIP type

Eastern (ET)

timezone

21231 ZIP code map

Cities in ZIP code 21231

Below are the cities the US Postal Service accepts for ZIP code 21231. Using any city not on this list may result in mail delivery delays.

City	Status
Baltimore	Acceptable
Baltimore	Preferred

Nearby ZIP codes

21202 Baltimore (1 mi) 21278 Baltimore (1.1 mi) 21233 Baltimore (1.1 mi) 21290 Baltimore (1.1 mi) 21273 Baltimore (1.1 mi) 21241 Baltimore (1.1 mi) 21289 Baltimore (1.1 mi) 21264 Baltimore (1.1 mi) 21287 Baltimore (1.1 mi) 21275 Baltimore (1.1 mi) 21279 Baltimore (1.1 mi) 21263 Baltimore (1.1 mi)

Demographics updated 06/2026

Population
Total population	14,780
Population density	16,989 / sq mi
State FIPS	24
County FIPS	510

Geography
Land area	0.87 sq mi
Water area	0.08 sq mi
Latitude	39.2879
Longitude	-76.5923
Timezone	Eastern (ET)
Area code	410/443/667

Total population by age

Gender

Race & ethnicity

Economics updated 06/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	35.0%	46.5%	28.2%
$50k – $100k	26.9%	28.0%	28.2%
$100k – $200k	25.9%	18.7%	30.1%
Over $200k	12.2%	6.8%	13.4%

Demographics & statistics

14,780

Population

16,989

People per sq mi

32.8

Median age

$88,091

Median household income

$62,267

Per capita income

$330,600

Median home value

$1,637

Median monthly rent

35.0%

Home ownership

19.2%

Poverty rate

4.0%

Unemployment

4,121

Housing units

65.5%

Bachelor's or higher

Age distribution

Male Female

377

Under 5

373

224

5–9

222

274

10–14

272

190

15–19

188

516

20–24

511

2,510

25–34

2,485

1,140

35–44

1,128

788

45–54

780

336

55–59

332

334

60–64

331

541

65–74

535

127

75–84

125

85+

← Male

Female →

Age summary

Group	Count	%
Under 18	2,024	13.7%
18 and over	12,756	86.3%
65 and over	1,469	9.9%
Median age	32.8 years

Race & ethnicity

White 57.7%

Black or African American 25%

Asian 6%

Two or more races 5.1%

Hispanic or Latino 3.8%

Other race 1.9%

American Indian / Alaska Native 0.3%

Group	Count	%
White	8,876	57.7%
Black or African American	3,849	25%
Asian	924	6%
Two or more races	784	5.1%
Hispanic or Latino	591	3.8%
Other race	294	1.9%
American Indian / Alaska Native	53	0.3%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	35.0%	46.5%	28.2%
$50k – $100k	26.9%	28.0%	28.2%
$100k – $200k	25.9%	18.7%	30.1%
Over $200k	12.2%	6.8%	13.4%

Under $10k 9.7%

$10k–$15k 3.5%

$15k–$25k 4.7%

$25k–$35k 5.0%

$35k–$50k 8.3%

$50k–$75k 14.5%

$75k–$100k 9.4%

$100k–$150k 17.6%

$150k–$200k 10.9%

$200k+ 16.5%

Range	% of households
Under $10k	9.7%
$10k–$15k	3.5%
$15k–$25k	4.7%
$25k–$35k	5.0%
$35k–$50k	8.3%
$50k–$75k	14.5%
$75k–$100k	9.4%
$100k–$150k	17.6%
$150k–$200k	10.9%
$200k+	16.5%
Median income	$88,091

Housing

Home values

Under $50k 1.7%

$50k–$100k 1.4%

$100k–$150k 2.6%

$150k–$200k 6.8%

$200k–$300k 29.2%

$300k–$500k 40.6%

$500k–$1M 14.8%

$1M+ 3.0%

Housing overview

Metric	Value
Median home value	$330,600
Median rent / month	$1,637
Owner occupied	35.0%
Renter occupied	65.0%
Vacant	15.1%
Single-family detached	3.0%
Large apartment buildings	25.1%
Mobile homes	0.2%
Median rooms	4.4
Avg household size (owned)	2.01

Year built

Era	%
2020 or later	1.2%
2010–2019	13.4%
2000–2009	9.0%
1990–1999	3.9%
1980–1989	5.1%
1970–1979	4.0%
1960–1969	4.4%
1950–1959	5.2%
1940–1949	3.5%
1939 or earlier	50.2%

Bedrooms

Size	% of units
No bedroom (studio)	4.9%
1 bedroom	27.8%
2 bedrooms	40.1%
3 bedrooms	21.7%
4 bedrooms	4.4%
5+ bedrooms	1.1%

Vehicles per household

Vehicles	% of households
No vehicle	22.5%
1 vehicle	50.8%
2 vehicles	23.0%
3 or more	3.8%

Heating fuel

Fuel type	%
Utility gas	54.9%
Electricity	41.3%
Propane / LP gas	1.0%
Fuel oil	1.4%
Solar	0.1%
No fuel used	0.8%

Households & families

Household type	Count	%
Married-couple family	1,864	23.8%
Cohabiting couple	807	10.3%
Male householder, no spouse	2,473	31.6%
Female householder, no spouse	2,674	34.2%
Households with children under 18	1,072	13.7%
Households with seniors (65+)	1,219	15.6%
Average household size	1.87

Marital status

Status	Male	Female
Never married	58.3%	54.5%
Married	28.6%	30.3%
Separated	3.2%	0.5%
Widowed	0.7%	5.4%
Divorced	9.2%	9.4%

Education

Less than 9th grade 2.0%

Some HS, no diploma 4.5%

HS graduate 14.9%

Some college, no degree 10.6%

Associate's degree 2.5%

Bachelor's degree 34.8%

Graduate / professional 30.7%

Metric	%
HS diploma or higher	93.5%
Bachelor's or higher	65.5%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	155	5.1%
Kindergarten	99	3.3%
Elementary school	865	28.7%
High school	326	10.8%
College / grad school	1,574	52.1%

Employment

Industry of employment

Education & healthcare 37.3%

Professional & management 19.4%

Finance & real estate 11.5%

Manufacturing 6.5%

Arts, food & hospitality 5.7%

Public administration 5.3%

Retail trade 3.8%

Other services 3.1%

Construction 2.6%

Transportation & utilities 2.1%

Information 2.1%

Agriculture & mining 0.2%

Wholesale trade 0.2%

Occupation

Category	%
Management, business & arts	78.6%
Service	7.6%
Sales & office	10.5%
Natural resources & construction	1.1%
Production & transportation	2.2%

Employment type

Type	%
Private sector	83.2%
Government	14.2%
Self-employed	1.9%
Unpaid family workers	0.7%

Commute

Method	%
Drive alone	45.8%
Carpool	6.2%
Public transit	3.9%
Walk	17.6%
Work from home	22.9%
Other means	3.7%
Avg commute (minutes)	25.6

Poverty

All people 19.2%

Under 18 years 38.8%

18 and over 16.2%

Married-couple families 8.3%

Female-led households 50.2%

Income support

Source	% of households
Social Security	15.9%
Retirement income	10.4%
Supplemental Security	5.2%
Cash public assistance	3.8%
Food stamps / SNAP	15.3%

Health indicators

Condition	%
Obesity	30.4%
High blood pressure	28.1%
High cholesterol	24.6%
Diabetes	8.5%
Heart disease	3.8%
Stroke	2.4%
Asthma	10.4%
Arthritis	17.7%
Kidney disease	2.3%
Pulmonary disease	4.5%
Cancer	4.3%

Behavior / access	%
Smoking	15.3%
Binge drinking	21.1%
No physical activity	18.4%
Less than 7 hrs sleep	33.8%
Depression	21.5%
Fair or poor health	12.1%
Poor mental health	15.3%
Poor physical health	7.6%
No health insurance	11.0%
Visited doctor (checkup)	74.2%
Visited dentist	63.5%
Cholesterol screening	90.1%
Teeth loss	11.1%

Veterans & disability

Veterans	Count	%
Civilian veterans	547	4.3%

Disability	%
Any disability	10.5%
Under 18	2.0%
18–64 years	9.6%
65 and over	29.0%

Health insurance coverage

Type	%
Private insurance	74.0%
Public insurance	30.6%
No insurance	2.9%
Uninsured under 19	1.1%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	14,030	94.9%
Spanish	493	3.5%
Other Indo-European	251	1.8%
Asian & Pacific Islander	74	0.5%
Other languages	58	0.4%

Place of birth & citizenship

Origin	Count	%
Native born (US)	13,130	88.8%
Born in same state	12,966	87.7%
Born in different state	6,882	46.6%
Foreign born	164	1.1%
Naturalized citizen	1,650	11.2%
Not a US citizen	744	45.1%

Ancestry

Ancestry	Count	%
Italian	1,887	12.8%
French	1,033	7%
Arab	369	2.5%
Polish	122	0.8%
Norwegian	108	0.7%

Ancestry	Count	%
German	50	0.3%
Dutch	44	0.3%
Irish	41	0.3%
English	32	0.2%

Technology access

Metric	% of households
Computer access	52.9%
Internet access	95.7%

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

Frequently asked questions about ZIP code 21231

What city is ZIP code 21231 in?

ZIP code 21231 is primarily assigned to Baltimore, Maryland.

What county is ZIP code 21231 in?

ZIP code 21231 falls within Baltimore City County, Maryland.

How educated is the population of ZIP code 21231?

66% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.

Is ZIP code 21231 mostly rentals?

65% of occupied units in ZIP code 21231 are renter-occupied.

What is the poverty rate in ZIP code 21231?

19% of residents in ZIP code 21231 live below the poverty line, above the national average.

What is the typical home value in ZIP code 21231?

The median home value in ZIP code 21231 is $330,600.

What timezone is ZIP code 21231 in?

ZIP code 21231 observes the EST timezone.