21723 ZIP Code — Cooksville, MD

Howard County, Maryland

ZIP code 21723 is located in Cooksville, Maryland, within Howard County. It covers approximately 3.61 square miles and serves a population of 689 residents. This is a standard ZIP code in the Eastern (ET) timezone, served by area code 443/410/667.

About ZIP code 21723

The housing stock consists of predominantly single-family detached homes. Most homes were built in the 2000s, giving the area an established character. Median home value is $852,400. Owner-occupancy is high at 97%, well above the national average.

Median household income is $250,001.

The dominant occupation class is management, business, and professional, with professional and management as the leading industry. An above-average commute of 39 minutes suggests many residents work outside the immediate area. Remote work is prevalent — 21% of workers work from home.

Educational attainment is high — 72% of residents hold a bachelor's degree or higher, well above the national average of 33%.

Overall, ZIP code 21723 reflects a community defined by a highly educated population, high homeownership, and a high rate of remote workers.

689

population

3.61

sq mi land

Standard

ZIP type

Eastern (ET)

timezone

21723 ZIP code map

Cities in ZIP code 21723

Below are the cities the US Postal Service accepts for ZIP code 21723. Using any city not on this list may result in mail delivery delays.

City	Status
Cooksville	Acceptable

Demographics updated 05/2026

Population
Total population	689
Population density	191 / sq mi
State FIPS	24
County FIPS	027

Geography
Land area	3.61 sq mi
Water area	0.03 sq mi
Latitude	39.3287
Longitude	-77.0181
Timezone	Eastern (ET)
Area code	443/410/667

Total population by age

Gender

Race & ethnicity

Economics updated 05/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	20.4%	17.1%	28.2%
$50k – $100k	8.6%	22.9%	28.2%
$100k – $200k	11.4%	34.8%	30.1%
Over $200k	59.6%	25.2%	13.4%

Demographics & statistics

689

Population

191

People per sq mi

52.4

Median age

$250,001

Median household income

$86,282

Per capita income

$852,400

Median home value

Median monthly rent

96.7%

Home ownership

0.0%

Poverty rate

3.8%

Unemployment

232

Housing units

71.5%

Bachelor's or higher

Age distribution

Male Female

Under 5

5–9

10–14

15–19

20–24

25–34

35–44

45–54

55–59

60–64

65–74

75–84

← Male

Female →

Age summary

Group	Count	%
Under 18	84	12.2%
18 and over	605	87.8%
65 and over	67	9.7%
Median age	52.4 years

Race & ethnicity

White 50.1%

Asian 47.8%

Black or African American 2.2%

Group	Count	%
White	345	50.1%
Asian	329	47.8%
Black or African American	15	2.2%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	20.4%	17.1%	28.2%
$50k – $100k	8.6%	22.9%	28.2%
$100k – $200k	11.4%	34.8%	30.1%
Over $200k	59.6%	25.2%	13.4%

$25k–$35k 3.3%

$35k–$50k 14.2%

$75k–$100k 14.2%

$150k–$200k 3.3%

$200k+ 65.0%

Range	% of households
$25k–$35k	3.3%
$35k–$50k	14.2%
$75k–$100k	14.2%
$150k–$200k	3.3%
$200k+	65.0%
Median income	$250,001

Housing

Home values

$300k–$500k 6.9%

$500k–$1M 75.4%

$1M+ 17.7%

Housing overview

Metric	Value
Median home value	$852,400
Median rent / month	$0
Owner occupied	96.7%
Renter occupied	3.3%
Vacant	0.0%
Single-family detached	96.7%
Large apartment buildings	0.0%
Mobile homes	0.0%
Median rooms	10.0
Avg household size (owned)	2.94

Year built

Era	%
2020 or later	0.0%
2010–2019	3.3%
2000–2009	47.9%
1990–1999	28.3%
1980–1989	2.9%
1970–1979	7.5%
1960–1969	0.0%
1950–1959	3.3%
1940–1949	0.0%
1939 or earlier	6.7%

Bedrooms

Size	% of units
No bedroom (studio)	0.0%
1 bedroom	0.0%
2 bedrooms	3.3%
3 bedrooms	17.1%
4 bedrooms	47.5%
5+ bedrooms	32.1%

Vehicles per household

Vehicles	% of households
No vehicle	0.0%
1 vehicle	3.3%
2 vehicles	45.8%
3 or more	50.8%

Heating fuel

Fuel type	%
Utility gas	42.5%
Electricity	44.6%
Propane / LP gas	3.3%
Fuel oil	9.6%

Households & families

Household type	Count	%
Married-couple family	232	96.7%
Cohabiting couple	0	0.0%
Male householder, no spouse	8	3.3%
Female householder, no spouse	0	0.0%
Households with children under 18	50	20.8%
Households with seniors (65+)	34	14.2%
Average household size	2.87

Marital status

Status	Male	Female
Never married	24.6%	24.4%
Married	75.4%	75.6%
Separated	0.0%	0.0%
Widowed	0.0%	0.0%
Divorced	0.0%	0.0%

Education

Less than 9th grade 0.0%

Some HS, no diploma 14.0%

HS graduate 4.2%

Some college, no degree 10.3%

Associate's degree 0.0%

Bachelor's degree 46.6%

Graduate / professional 24.9%

Metric	%
HS diploma or higher	86.0%
Bachelor's or higher	71.5%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	12	6.6%
Kindergarten	0	0.0%
Elementary school	49	27.1%
High school	42	23.2%
College / grad school	78	43.1%

Employment

Industry of employment

Professional & management 32.2%

Retail trade 30.7%

Finance & real estate 11.6%

Education & healthcare 9.5%

Arts, food & hospitality 8.3%

Wholesale trade 4.8%

Construction 1.5%

Public administration 1.5%

Occupation

Category	%
Management, business & arts	57.5%
Service	15.1%
Sales & office	26.1%
Natural resources & construction	0.0%
Production & transportation	1.2%

Employment type

Type	%
Private sector	82.4%
Government	12.2%
Self-employed	5.4%
Unpaid family workers	0.0%

Commute

Method	%
Drive alone	77.2%
Carpool	0.0%
Public transit	0.0%
Walk	1.7%
Work from home	21.2%
Other means	0.0%
Avg commute (minutes)	38.7

Poverty

All people 0.0%

Under 18 years 0.0%

18 and over 0.0%

Married-couple families 0.0%

Female-led households 0.0%

Income support

Source	% of households
Social Security	14.2%
Retirement income	7.5%
Supplemental Security	0.0%
Cash public assistance	0.0%
Food stamps / SNAP	0.0%

Health indicators

Condition	%
Obesity	26.6%
High blood pressure	29.2%
High cholesterol	32.9%
Diabetes	7.8%
Heart disease	4.0%
Stroke	2.0%
Asthma	8.5%
Arthritis	19.4%
Kidney disease	2.0%
Pulmonary disease	3.8%
Cancer	5.8%

Behavior / access	%
Smoking	10.2%
Binge drinking	13.6%
No physical activity	16.1%
Less than 7 hrs sleep	31.7%
Depression	16.2%
Fair or poor health	8.0%
Poor mental health	11.5%
Poor physical health	6.3%
No health insurance	7.1%
Visited doctor (checkup)	74.9%
Visited dentist	74.8%
Cholesterol screening	94.2%
Teeth loss	6.4%

Veterans & disability

Veterans	Count	%
Civilian veterans	17	2.8%

Disability	%
Any disability	6.0%
Under 18	0.0%
18–64 years	1.5%
65 and over	49.3%

Health insurance coverage

Type	%
Private insurance	100.0%
Public insurance	9.7%
No insurance	0.0%
Uninsured under 19	0.0%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	677	98.3%
Spanish	32	4.7%
Other Indo-European	0	0.0%
Asian & Pacific Islander	0	0.0%
Other languages	32	4.7%

Place of birth & citizenship

Origin	Count	%
Native born (US)	443	64.3%
Born in same state	443	64.3%
Born in different state	286	41.5%
Foreign born	0	0.0%
Naturalized citizen	246	35.7%
Not a US citizen	197	80.1%

Ancestry

Ancestry	Count	%
Italian	84	12.2%
French	49	7.1%
German	25	3.6%

Ancestry	Count	%
Irish	16	2.3%
Arab	8	1.2%

Technology access

Metric	% of households
Computer access	34.8%
Internet access	100.0%

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

Frequently asked questions about ZIP code 21723

What city is ZIP code 21723 in?

ZIP code 21723 is primarily assigned to Cooksville, Maryland.

What county is ZIP code 21723 in?

ZIP code 21723 falls within Howard County, Maryland.

How educated is the population of ZIP code 21723?

72% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.

Is ZIP code 21723 mostly owner-occupied?

97% of occupied units in ZIP code 21723 are owner-occupied, well above the national average.

What is the median household income in ZIP code 21723?

The median household income in ZIP code 21723 is $250,001, above the national median of ~$75,000.

What is the typical home value in ZIP code 21723?

The median home value in ZIP code 21723 is $852,400.

What timezone is ZIP code 21723 in?

ZIP code 21723 observes the EST timezone.