21918 ZIP Code — Conowingo, MD

Cecil County, Maryland

ZIP code 21918 is located in Conowingo, Maryland, within Cecil County. It covers approximately 17.57 square miles and serves a population of 4,462 residents. This is a standard ZIP code in the Eastern (ET) timezone, served by area code 410.

About ZIP code 21918

The housing stock consists of predominantly single-family detached homes. Most homes were built in the 1990s, giving the area an established character. Median home value is $295,700. Owner-occupancy is high at 89%, well above the national average.

Median household income is $78,691. The poverty rate of 6% is below the national average. 37% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is management, business, and professional, with public administration as the leading industry. An above-average commute of 36 minutes suggests many residents work outside the immediate area.

College attainment at 16% is below the national average, consistent with a trades and production-oriented local economy.

Overall, ZIP code 21918 reflects a community defined by a trades-oriented workforce, high homeownership, and a significant Social Security-dependent population.

4,462

population

17.57

sq mi land

Standard

ZIP type

Eastern (ET)

timezone

21918 ZIP code map

Cities in ZIP code 21918

Below are the cities the US Postal Service accepts for ZIP code 21918. Using any city not on this list may result in mail delivery delays.

City	Status
Conowingo	Preferred

Nearby ZIP codes

21034 Darlington (3.2 mi) 21917 Colora (3.8 mi) 17563 Peach Bottom (6.3 mi) 21904 Port Deposit (6.4 mi) 21911 Rising Sun (6.5 mi) 21160 Whiteford (7.9 mi) 19362 Nottingham (8.2 mi) 21028 Churchville (8.5 mi) 21078 Havre De Grace (8.5 mi) 21903 Perryville (10 mi) 17314 Delta (10.3 mi) 21154 Street (11.2 mi)

Demographics updated 05/2026

Population
Total population	4,462
Population density	254 / sq mi
State FIPS	24
County FIPS	015

Geography
Land area	17.57 sq mi
Water area	2.55 sq mi
Latitude	39.6791
Longitude	-76.1704
Timezone	Eastern (ET)
Area code	410

Total population by age

Gender

Race & ethnicity

Economics updated 05/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	23.7%	31.4%	28.2%
$50k – $100k	37.6%	31.8%	28.2%
$100k – $200k	33.3%	29.7%	30.1%
Over $200k	5.5%	7.1%	13.4%

Demographics & statistics

4,462

Population

254

People per sq mi

42.7

Median age

$78,691

Median household income

$38,461

Per capita income

$295,700

Median home value

$953

Median monthly rent

88.8%

Home ownership

6.2%

Poverty rate

3.9%

Unemployment

1,571

Housing units

16.3%

Bachelor's or higher

Age distribution

Male Female

126

Under 5

124

155

5–9

153

157

10–14

154

110

15–19

108

20–24

185

25–34

182

365

35–44

360

290

45–54

286

187

55–59

184

189

60–64

186

219

65–74

216

127

75–84

126

85+

← Male

Female →

Age summary

Group	Count	%
Under 18	991	22.2%
18 and over	3,471	77.8%
65 and over	772	17.3%
Median age	42.7 years

Race & ethnicity

White 87%

Two or more races 6.5%

Hispanic or Latino 3.4%

Black or African American 2.2%

American Indian / Alaska Native 0.5%

Asian 0.3%

Other race 0.2%

Group	Count	%
White	4,018	87%
Two or more races	302	6.5%
Hispanic or Latino	156	3.4%
Black or African American	100	2.2%
American Indian / Alaska Native	21	0.5%
Asian	12	0.3%
Other race	9	0.2%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	23.7%	31.4%	28.2%
$50k – $100k	37.6%	31.8%	28.2%
$100k – $200k	33.3%	29.7%	30.1%
Over $200k	5.5%	7.1%	13.4%

Under $10k 1.0%

$10k–$15k 4.0%

$15k–$25k 5.3%

$25k–$35k 2.8%

$35k–$50k 13.1%

$50k–$75k 20.6%

$75k–$100k 11.8%

$100k–$150k 21.3%

$150k–$200k 7.9%

$200k+ 12.2%

Range	% of households
Under $10k	1.0%
$10k–$15k	4.0%
$15k–$25k	5.3%
$25k–$35k	2.8%
$35k–$50k	13.1%
$50k–$75k	20.6%
$75k–$100k	11.8%
$100k–$150k	21.3%
$150k–$200k	7.9%
$200k+	12.2%
Median income	$78,691

Housing

Home values

Under $50k 6.2%

$50k–$100k 3.0%

$100k–$150k 3.9%

$150k–$200k 10.0%

$200k–$300k 28.5%

$300k–$500k 40.9%

$500k–$1M 7.4%

Housing overview

Metric	Value
Median home value	$295,700
Median rent / month	$953
Owner occupied	88.8%
Renter occupied	11.2%
Vacant	4.2%
Single-family detached	84.4%
Large apartment buildings	0.0%
Mobile homes	13.0%
Median rooms	7.1
Avg household size (owned)	2.66

Year built

Era	%
2020 or later	0.6%
2010–2019	7.7%
2000–2009	13.4%
1990–1999	24.9%
1980–1989	21.1%
1970–1979	5.7%
1960–1969	7.3%
1950–1959	4.4%
1940–1949	1.6%
1939 or earlier	13.2%

Bedrooms

Size	% of units
No bedroom (studio)	1.9%
1 bedroom	3.1%
2 bedrooms	19.8%
3 bedrooms	45.5%
4 bedrooms	26.9%
5+ bedrooms	2.8%

Vehicles per household

Vehicles	% of households
No vehicle	1.7%
1 vehicle	27.9%
2 vehicles	33.9%
3 or more	36.5%

Heating fuel

Fuel type	%
Utility gas	5.7%
Electricity	38.3%
Propane / LP gas	25.0%
Fuel oil	19.1%
Wood	9.7%
No fuel used	1.8%

Households & families

Household type	Count	%
Married-couple family	1,150	68.2%
Cohabiting couple	87	5.2%
Male householder, no spouse	187	11.1%
Female householder, no spouse	261	15.5%
Households with children under 18	496	29.4%
Households with seniors (65+)	532	31.6%
Average household size	2.64

Marital status

Status	Male	Female
Never married	19.4%	22.2%
Married	68.7%	61.7%
Separated	0.0%	0.9%
Widowed	0.0%	7.7%
Divorced	12.0%	7.6%

Education

Less than 9th grade 0.9%

Some HS, no diploma 6.2%

HS graduate 40.9%

Some college, no degree 23.7%

Associate's degree 12.1%

Bachelor's degree 7.5%

Graduate / professional 8.9%

Metric	%
HS diploma or higher	92.9%
Bachelor's or higher	16.3%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	110	11.4%
Kindergarten	74	7.7%
Elementary school	508	52.6%
High school	189	19.6%
College / grad school	85	8.8%

Employment

Industry of employment

Public administration 18.5%

Education & healthcare 18.0%

Construction 16.8%

Manufacturing 9.8%

Professional & management 9.7%

Retail trade 9.2%

Transportation & utilities 5.5%

Arts, food & hospitality 4.2%

Finance & real estate 3.5%

Information 2.3%

Wholesale trade 1.5%

Agriculture & mining 0.6%

Other services 0.5%

Occupation

Category	%
Management, business & arts	38.3%
Service	15.2%
Sales & office	15.2%
Natural resources & construction	15.1%
Production & transportation	16.2%

Employment type

Type	%
Private sector	67.0%
Government	28.7%
Self-employed	3.2%
Unpaid family workers	1.1%

Commute

Method	%
Drive alone	80.0%
Carpool	7.4%
Public transit	0.0%
Walk	1.0%
Work from home	11.5%
Other means	0.0%
Avg commute (minutes)	36.3

Poverty

All people 6.2%

Under 18 years 0.9%

18 and over 7.7%

Married-couple families 1.4%

Female-led households 52.6%

Income support

Source	% of households
Social Security	36.6%
Retirement income	30.9%
Supplemental Security	4.2%
Cash public assistance	1.4%
Food stamps / SNAP	7.0%

Health indicators

Condition	%
Obesity	37.5%
High blood pressure	35.1%
High cholesterol	34.2%
Diabetes	9.2%
Heart disease	5.5%
Stroke	2.6%
Asthma	9.4%
Arthritis	25.3%
Kidney disease	2.4%
Pulmonary disease	6.5%
Cancer	6.4%

Behavior / access	%
Smoking	19.3%
Binge drinking	17.6%
No physical activity	23.9%
Less than 7 hrs sleep	35.6%
Depression	20.6%
Fair or poor health	12.3%
Poor mental health	14.9%
Poor physical health	9.1%
No health insurance	10.0%
Visited doctor (checkup)	73.1%
Visited dentist	64.3%
Cholesterol screening	91.0%
Teeth loss	11.7%

Veterans & disability

Veterans	Count	%
Civilian veterans	302	8.7%

Disability	%
Any disability	14.8%
Under 18	2.0%
18–64 years	13.9%
65 and over	34.5%

Health insurance coverage

Type	%
Private insurance	75.0%
Public insurance	36.5%
No insurance	2.1%
Uninsured under 19	0.0%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	4,212	94.4%
Spanish	65	1.5%
Other Indo-European	21	0.5%
Asian & Pacific Islander	44	1.0%
Other languages	0	0.0%

Place of birth & citizenship

Origin	Count	%
Native born (US)	4,413	98.9%
Born in same state	4,405	98.7%
Born in different state	2,871	64.3%
Foreign born	8	0.2%
Naturalized citizen	49	1.1%
Not a US citizen	38	77.6%

Ancestry

Ancestry	Count	%
French	487	10.9%
Italian	478	10.7%
Arab	421	9.4%
Polish	55	1.2%

Ancestry	Count	%
English	29	0.6%
Irish	17	0.4%
German	11	0.2%
Norwegian	11	0.2%

Technology access

Metric	% of households
Computer access	37.8%
Internet access	93.4%

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

Frequently asked questions about ZIP code 21918

What city is ZIP code 21918 in?

ZIP code 21918 is primarily assigned to Conowingo, Maryland.

What county is ZIP code 21918 in?

ZIP code 21918 falls within Cecil County, Maryland.

Is ZIP code 21918 mostly owner-occupied?

89% of occupied units in ZIP code 21918 are owner-occupied, well above the national average.

Does ZIP code 21918 have a large retiree population?

37% of households in ZIP code 21918 receive Social Security income, suggesting a significant retiree or disability population.

What is the population of ZIP code 21918?

ZIP code 21918 has an estimated population of 4,462 residents, with a density of 254 people per square mile.

What is the typical home value in ZIP code 21918?

The median home value in ZIP code 21918 is $295,700.

What timezone is ZIP code 21918 in?

ZIP code 21918 observes the EST timezone.