21042 ZIP Code — Ellicott City, MD

Howard County, Maryland

ZIP code 21042 is located in Ellicott City, Maryland, within Howard County. It covers approximately 37.00 square miles and serves a population of 42,528 residents. This is a standard ZIP code in the Eastern (ET) timezone, served by area code 410/443.

About ZIP code 21042

The housing stock consists of predominantly single-family detached homes. Most homes were built in the 1980s, giving the area an established character. Median home value is $650,900. Owner-occupancy is high at 84%, well above the national average.

The gap between median ($178,207) and mean household income suggests income inequality — a small number of higher earners pull the average up. The poverty rate of 4% is below the national average.

The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. The average commute of 29 minutes is near the national average. Remote work is prevalent — 23% of workers work from home.

Educational attainment is high — 73% of residents hold a bachelor's degree or higher, well above the national average of 33%.

Overall, ZIP code 21042 reflects a community defined by a highly educated population, high homeownership, and a high rate of remote workers.

42,528

population

37.00

sq mi land

Standard

ZIP type

Eastern (ET)

timezone

21042 ZIP code map

Cities in ZIP code 21042

Below are the cities the US Postal Service accepts for ZIP code 21042. Using any city not on this list may result in mail delivery delays.

City	Status
Ellicott City	Acceptable
Ellicott City	Preferred

Nearby ZIP codes

21794 West Friendship (4.1 mi) 21104 Marriottsville (4.6 mi) 21163 Woodstock (4.9 mi) 21044 Columbia (5.1 mi) 21029 Clarksville (5.8 mi) 21043 Ellicott City (5.9 mi) 21045 Columbia (6.2 mi) 21737 Glenelg (6.4 mi) 21036 Dayton (6.5 mi) 21738 Glenwood (6.8 mi) 21244 Windsor Mill (7.3 mi) 21046 Columbia (7.8 mi)

Demographics updated 05/2026

Population
Total population	42,528
Population density	1,149 / sq mi
State FIPS	24
County FIPS	027

Geography
Land area	37.00 sq mi
Water area	0.17 sq mi
Latitude	39.2767
Longitude	-76.8994
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	10.4%	17.1%	28.2%
$50k – $100k	19.4%	22.9%	28.2%
$100k – $200k	33.4%	34.8%	30.1%
Over $200k	36.8%	25.2%	13.4%

Demographics & statistics

42,528

Population

1,149

People per sq mi

44.6

Median age

$178,207

Median household income

$73,782

Per capita income

$650,900

Median home value

$2,197

Median monthly rent

84.4%

Home ownership

4.1%

Poverty rate

2.7%

Unemployment

12,825

Housing units

73.3%

Bachelor's or higher

Age distribution

Male Female

925

Under 5

905

1,188

5–9

1,163

2,144

10–14

2,098

1,677

15–19

1,641

850

20–24

831

1,351

25–34

1,322

2,755

35–44

2,696

3,412

45–54

3,338

1,852

55–59

1,813

1,301

60–64

1,273

2,354

65–74

2,304

1,186

75–84

1,161

499

85+

489

← Male

Female →

Age summary

Group	Count	%
Under 18	10,871	25.6%
18 and over	31,657	74.4%
65 and over	7,993	18.8%
Median age	44.6 years

Race & ethnicity

White 56.6%

Asian 29.6%

Two or more races 5.2%

Black or African American 4.3%

Hispanic or Latino 2.8%

Other race 1%

American Indian / Alaska Native 0.4%

Native Hawaiian / Pacific Islander 0.1%

Group	Count	%
White	24,759	56.6%
Asian	12,951	29.6%
Two or more races	2,291	5.2%
Black or African American	1,873	4.3%
Hispanic or Latino	1,213	2.8%
Other race	437	1%
American Indian / Alaska Native	155	0.4%
Native Hawaiian / Pacific Islander	62	0.1%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	10.4%	17.1%	28.2%
$50k – $100k	19.4%	22.9%	28.2%
$100k – $200k	33.4%	34.8%	30.1%
Over $200k	36.8%	25.2%	13.4%

Under $10k 1.5%

$10k–$15k 1.2%

$15k–$25k 1.5%

$25k–$35k 2.4%

$35k–$50k 4.4%

$50k–$75k 7.0%

$75k–$100k 8.0%

$100k–$150k 14.6%

$150k–$200k 17.2%

$200k+ 42.1%

Range	% of households
Under $10k	1.5%
$10k–$15k	1.2%
$15k–$25k	1.5%
$25k–$35k	2.4%
$35k–$50k	4.4%
$50k–$75k	7.0%
$75k–$100k	8.0%
$100k–$150k	14.6%
$150k–$200k	17.2%
$200k+	42.1%
Median income	$178,207

Housing

Home values

Under $50k 0.8%

$50k–$100k 1.2%

$100k–$150k 0.3%

$150k–$200k 2.1%

$200k–$300k 3.0%

$300k–$500k 12.2%

$500k–$1M 71.9%

$1M+ 8.5%

Housing overview

Metric	Value
Median home value	$650,900
Median rent / month	$2,197
Owner occupied	84.4%
Renter occupied	15.6%
Vacant	1.6%
Single-family detached	75.5%
Large apartment buildings	5.6%
Mobile homes	0.0%
Median rooms	8.3
Avg household size (owned)	2.93

Year built

Era	%
2020 or later	0.2%
2010–2019	12.0%
2000–2009	11.0%
1990–1999	16.0%
1980–1989	29.1%
1970–1979	14.0%
1960–1969	10.2%
1950–1959	5.7%
1940–1949	0.8%
1939 or earlier	1.0%

Bedrooms

Size	% of units
No bedroom (studio)	1.5%
1 bedroom	3.7%
2 bedrooms	12.0%
3 bedrooms	20.7%
4 bedrooms	41.8%
5+ bedrooms	20.3%

Vehicles per household

Vehicles	% of households
No vehicle	3.1%
1 vehicle	20.9%
2 vehicles	46.8%
3 or more	29.2%

Heating fuel

Fuel type	%
Utility gas	50.6%
Electricity	42.5%
Propane / LP gas	1.0%
Fuel oil	5.0%
Wood	0.4%
Solar	0.2%
No fuel used	0.1%

Households & families

Household type	Count	%
Married-couple family	10,825	72.6%
Cohabiting couple	303	2.0%
Male householder, no spouse	1,797	12.0%
Female householder, no spouse	1,988	13.3%
Households with children under 18	6,151	41.2%
Households with seniors (65+)	5,266	35.3%
Average household size	2.84

Marital status

Status	Male	Female
Never married	24.9%	19.5%
Married	67.2%	67.3%
Separated	1.0%	0.6%
Widowed	3.7%	7.4%
Divorced	3.2%	5.2%

Education

Less than 9th grade 0.9%

Some HS, no diploma 2.2%

HS graduate 9.0%

Some college, no degree 9.4%

Associate's degree 5.2%

Bachelor's degree 33.5%

Graduate / professional 39.8%

Metric	%
HS diploma or higher	96.9%
Bachelor's or higher	73.3%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	503	4.1%
Kindergarten	476	3.9%
Elementary school	5,235	43.1%
High school	3,482	28.6%
College / grad school	2,464	20.3%

Employment

Industry of employment

Education & healthcare 26.9%

Professional & management 23.2%

Public administration 10.5%

Finance & real estate 7.0%

Manufacturing 6.2%

Arts, food & hospitality 6.0%

Retail trade 5.3%

Construction 4.5%

Other services 3.9%

Transportation & utilities 3.2%

Information 1.9%

Wholesale trade 1.0%

Agriculture & mining 0.2%

Occupation

Category	%
Management, business & arts	73.9%
Service	8.3%
Sales & office	11.4%
Natural resources & construction	3.2%
Production & transportation	3.2%

Employment type

Type	%
Private sector	70.7%
Government	23.7%
Self-employed	5.4%
Unpaid family workers	0.3%

Commute

Method	%
Drive alone	69.5%
Carpool	4.8%
Public transit	0.5%
Walk	1.3%
Work from home	22.9%
Other means	1.0%
Avg commute (minutes)	28.9

Poverty

All people 4.1%

Under 18 years 4.7%

18 and over 3.9%

Married-couple families 2.5%

Female-led households 11.2%

Income support

Source	% of households
Social Security	29.8%
Retirement income	30.5%
Supplemental Security	1.3%
Cash public assistance	0.8%
Food stamps / SNAP	2.1%

Health indicators

Condition	%
Obesity	24.1%
High blood pressure	30.8%
High cholesterol	35.6%
Diabetes	8.3%
Heart disease	4.7%
Stroke	2.1%
Asthma	8.0%
Arthritis	21.1%
Kidney disease	2.2%
Pulmonary disease	3.8%
Cancer	7.0%

Behavior / access	%
Smoking	7.8%
Binge drinking	12.1%
No physical activity	15.0%
Less than 7 hrs sleep	29.4%
Depression	15.0%
Fair or poor health	7.4%
Poor mental health	10.2%
Poor physical health	6.0%
No health insurance	5.8%
Visited doctor (checkup)	76.8%
Visited dentist	77.5%
Cholesterol screening	95.0%
Teeth loss	5.1%

Veterans & disability

Veterans	Count	%
Civilian veterans	2,139	6.8%

Disability	%
Any disability	7.8%
Under 18	4.7%
18–64 years	3.9%
65 and over	23.4%

Health insurance coverage

Type	%
Private insurance	88.9%
Public insurance	23.6%
No insurance	2.6%
Uninsured under 19	1.9%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	40,698	95.7%
Spanish	3,225	7.9%
Other Indo-European	90	0.2%
Asian & Pacific Islander	451	1.1%
Other languages	2,664	6.5%

Place of birth & citizenship

Origin	Count	%
Native born (US)	31,780	74.7%
Born in same state	31,090	73.1%
Born in different state	16,714	39.3%
Foreign born	690	1.6%
Naturalized citizen	10,748	25.3%
Not a US citizen	7,076	65.8%

Ancestry

Ancestry	Count	%
Italian	5,691	13.4%
French	4,507	10.6%
Arab	1,227	2.9%
Polish	539	1.3%
Dutch	243	0.6%

Ancestry	Count	%
English	232	0.5%
Irish	110	0.3%
German	89	0.2%
Norwegian	65	0.2%

Technology access

Metric	% of households
Computer access	35.1%
Internet access	98.9%

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

Frequently asked questions about ZIP code 21042

What city is ZIP code 21042 in?

ZIP code 21042 is primarily assigned to Ellicott City, Maryland.

What county is ZIP code 21042 in?

ZIP code 21042 falls within Howard County, Maryland.

How educated is the population of ZIP code 21042?

73% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.

Is ZIP code 21042 mostly owner-occupied?

84% of occupied units in ZIP code 21042 are owner-occupied, well above the national average.

What is the median household income in ZIP code 21042?

The median household income in ZIP code 21042 is $178,207, above the national median of ~$75,000.

What is the typical home value in ZIP code 21042?

The median home value in ZIP code 21042 is $650,900.

What timezone is ZIP code 21042 in?

ZIP code 21042 observes the EST timezone.