20878 ZIP Code — Gaithersburg, MD

Montgomery County, Maryland

ZIP code 20878 is located in Gaithersburg, Maryland, within Montgomery County. It covers approximately 20.45 square miles and serves a population of 65,954 residents. This is a standard ZIP code in the Eastern (ET) timezone, served by area code 301.

About ZIP code 20878

The housing stock consists of a mix of housing types. Most homes were built in the 1980s, giving the area an established character. Median home value is $654,500. Owner-occupancy sits near the national average at 69%.

The gap between median ($141,902) 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 professional and management as the leading industry. The average commute of 31 minutes is near the national average. Remote work is prevalent — 26% of workers work from home.

Educational attainment is high — 71% of residents hold a bachelor's degree or higher, well above the national average of 33%.

Overall, ZIP code 20878 reflects a community defined by a highly educated population and a high rate of remote workers.

65,954

population

20.45

sq mi land

Standard

ZIP type

Eastern (ET)

timezone

20878 ZIP code map

Cities in ZIP code 20878

Below are the cities the US Postal Service accepts for ZIP code 20878. Using any city not on this list may result in mail delivery delays.

City	Status
Gaithersburg	Acceptable
Gaithersburg	Preferred

Nearby ZIP codes

20874 Germantown (3 mi) 20899 Gaithersburg (3.2 mi) 20850 Rockville (3.3 mi) 20877 Gaithersburg (4 mi) 20857 Rockville (5.3 mi) 20886 Montgomery Village (5.4 mi) 20879 Gaithersburg (5.6 mi) 20854 Potomac (6 mi) 20855 Derwood (6.1 mi) 20841 Boyds (6.4 mi) 20876 Germantown (6.7 mi) 20851 Rockville (6.9 mi)

Demographics updated 06/2026

Population
Total population	65,954
Population density	3,225 / sq mi
State FIPS	24
County FIPS	031

Geography
Land area	20.45 sq mi
Water area	0.38 sq mi
Latitude	39.1119
Longitude	-77.2452
Timezone	Eastern (ET)
Area code	301

Total population by age

Gender

Race & ethnicity

Economics updated 06/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	14.0%	20.6%	28.2%
$50k – $100k	24.2%	24.2%	28.2%
$100k – $200k	32.4%	31.9%	30.1%
Over $200k	29.4%	23.3%	13.4%

Demographics & statistics

65,954

Population

3,225

People per sq mi

40.3

Median age

$141,902

Median household income

$69,172

Per capita income

$654,500

Median home value

$2,068

Median monthly rent

69.4%

Home ownership

4.4%

Poverty rate

4.2%

Unemployment

17,830

Housing units

71.0%

Bachelor's or higher

Age distribution

Male Female

1,671

Under 5

1,810

1,890

5–9

2,048

2,161

10–14

2,342

2,146

15–19

2,326

1,995

20–24

2,162

3,428

25–34

3,715

4,644

35–44

5,032

4,691

45–54

5,082

2,401

55–59

2,601

2,092

60–64

2,266

2,878

65–74

3,118

1,299

75–84

1,408

359

85+

389

← Male

Female →

Age summary

Group	Count	%
Under 18	14,861	22.5%
18 and over	51,093	77.5%
65 and over	9,451	14.3%
Median age	40.3 years

Race & ethnicity

White 44.8%

Asian 24.5%

Black or African American 9.2%

Hispanic or Latino 9.1%

Two or more races 7.4%

Other race 4.8%

American Indian / Alaska Native 0.3%

Group	Count	%
White	32,481	44.8%
Asian	17,775	24.5%
Black or African American	6,654	9.2%
Hispanic or Latino	6,624	9.1%
Two or more races	5,382	7.4%
Other race	3,459	4.8%
American Indian / Alaska Native	203	0.3%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	14.0%	20.6%	28.2%
$50k – $100k	24.2%	24.2%	28.2%
$100k – $200k	32.4%	31.9%	30.1%
Over $200k	29.4%	23.3%	13.4%

Under $10k 1.8%

$10k–$15k 1.0%

$15k–$25k 1.3%

$25k–$35k 4.0%

$35k–$50k 3.9%

$50k–$75k 9.7%

$75k–$100k 12.6%

$100k–$150k 18.8%

$150k–$200k 13.5%

$200k+ 33.4%

Range	% of households
Under $10k	1.8%
$10k–$15k	1.0%
$15k–$25k	1.3%
$25k–$35k	4.0%
$35k–$50k	3.9%
$50k–$75k	9.7%
$75k–$100k	12.6%
$100k–$150k	18.8%
$150k–$200k	13.5%
$200k+	33.4%
Median income	$141,902

Housing

Home values

Under $50k 0.7%

$50k–$100k 0.6%

$100k–$150k 0.9%

$150k–$200k 1.9%

$200k–$300k 3.5%

$300k–$500k 23.7%

$500k–$1M 56.8%

$1M+ 11.8%

Housing overview

Metric	Value
Median home value	$654,500
Median rent / month	$2,068
Owner occupied	69.4%
Renter occupied	30.6%
Vacant	4.0%
Single-family detached	42.4%
Large apartment buildings	11.3%
Mobile homes	0.1%
Median rooms	6.7
Avg household size (owned)	2.72

Year built

Era	%
2020 or later	0.4%
2010–2019	7.6%
2000–2009	12.9%
1990–1999	19.0%
1980–1989	33.3%
1970–1979	18.4%
1960–1969	6.5%
1950–1959	0.7%
1940–1949	0.5%
1939 or earlier	0.7%

Bedrooms

Size	% of units
No bedroom (studio)	2.4%
1 bedroom	8.7%
2 bedrooms	19.5%
3 bedrooms	28.5%
4 bedrooms	29.2%
5+ bedrooms	11.8%

Vehicles per household

Vehicles	% of households
No vehicle	3.7%
1 vehicle	32.2%
2 vehicles	45.8%
3 or more	18.2%

Heating fuel

Fuel type	%
Utility gas	50.6%
Electricity	42.8%
Propane / LP gas	1.4%
Fuel oil	3.5%
Solar	0.8%
No fuel used	0.3%

Households & families

Household type	Count	%
Married-couple family	15,192	62.7%
Cohabiting couple	818	3.4%
Male householder, no spouse	2,602	10.7%
Female householder, no spouse	5,610	23.2%
Households with children under 18	8,888	36.7%
Households with seniors (65+)	6,327	26.1%
Average household size	2.72

Marital status

Status	Male	Female
Never married	30.1%	27.5%
Married	63.6%	56.5%
Separated	0.4%	1.7%
Widowed	1.1%	4.9%
Divorced	4.8%	9.4%

Education

Less than 9th grade 2.1%

Some HS, no diploma 2.0%

HS graduate 9.6%

Some college, no degree 10.1%

Associate's degree 5.1%

Bachelor's degree 35.6%

Graduate / professional 35.4%

Metric	%
HS diploma or higher	95.9%
Bachelor's or higher	71.0%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	1,071	6.4%
Kindergarten	537	3.2%
Elementary school	6,958	41.4%
High school	3,926	23.4%
College / grad school	4,321	25.7%

Employment

Industry of employment

Professional & management 28.6%

Education & healthcare 18.2%

Public administration 12.1%

Arts, food & hospitality 6.7%

Retail trade 6.2%

Finance & real estate 6.0%

Other services 5.7%

Manufacturing 5.4%

Construction 4.3%

Transportation & utilities 2.9%

Information 2.6%

Wholesale trade 1.1%

Agriculture & mining 0.2%

Occupation

Category	%
Management, business & arts	65.4%
Service	9.5%
Sales & office	16.5%
Natural resources & construction	4.2%
Production & transportation	4.4%

Employment type

Type	%
Private sector	72.2%
Government	22.6%
Self-employed	5.0%
Unpaid family workers	0.2%

Commute

Method	%
Drive alone	57.2%
Carpool	7.8%
Public transit	5.0%
Walk	1.5%
Work from home	26.0%
Other means	2.4%
Avg commute (minutes)	30.6

Poverty

All people 4.4%

Under 18 years 5.4%

18 and over 4.1%

Married-couple families 1.7%

Female-led households 8.0%

Income support

Source	% of households
Social Security	21.1%
Retirement income	19.5%
Supplemental Security	1.3%
Cash public assistance	2.6%
Food stamps / SNAP	4.3%

Health indicators

Condition	%
Obesity	19.2%
High blood pressure	24.5%
High cholesterol	32.0%
Diabetes	6.9%
Heart disease	3.6%
Stroke	1.8%
Asthma	7.6%
Arthritis	15.8%
Kidney disease	1.9%
Pulmonary disease	3.2%
Cancer	5.0%

Behavior / access	%
Smoking	7.9%
Binge drinking	13.0%
No physical activity	14.4%
Less than 7 hrs sleep	28.9%
Depression	14.8%
Fair or poor health	7.3%
Poor mental health	10.6%
Poor physical health	5.4%
No health insurance	9.2%
Visited doctor (checkup)	71.7%
Visited dentist	72.5%
Cholesterol screening	93.5%
Teeth loss	4.6%

Veterans & disability

Veterans	Count	%
Civilian veterans	1,830	3.6%

Disability	%
Any disability	6.7%
Under 18	2.9%
18–64 years	5.3%
65 and over	19.2%

Health insurance coverage

Type	%
Private insurance	84.5%
Public insurance	22.5%
No insurance	4.8%
Uninsured under 19	2.5%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	62,473	94.7%
Spanish	8,585	13.7%
Other Indo-European	2,555	4.1%
Asian & Pacific Islander	2,255	3.6%
Other languages	3,670	5.9%

Place of birth & citizenship

Origin	Count	%
Native born (US)	42,708	64.8%
Born in same state	41,546	63.0%
Born in different state	16,982	25.7%
Foreign born	1,162	1.8%
Naturalized citizen	23,246	35.2%
Not a US citizen	13,201	56.8%

Ancestry

Ancestry	Count	%
Italian	4,853	7.4%
French	4,541	6.9%
Arab	1,705	2.6%
Polish	509	0.8%
English	497	0.8%

Ancestry	Count	%
Irish	306	0.5%
Dutch	244	0.4%
Norwegian	172	0.3%
German	120	0.2%

Technology access

Metric	% of households
Computer access	36.7%
Internet access	98.9%

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

Frequently asked questions about ZIP code 20878

What part of Gaithersburg is ZIP code 20878?

ZIP code 20878 covers a portion of Gaithersburg, Maryland, within Montgomery County.

What county is ZIP code 20878 in?

ZIP code 20878 falls within Montgomery County, Maryland.

How educated is the population of ZIP code 20878?

71% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.

What is the median household income in ZIP code 20878?

The median household income in ZIP code 20878 is $141,902, above the national median of ~$75,000.

What is the typical home value in ZIP code 20878?

The median home value in ZIP code 20878 is $654,500.

What is the population of ZIP code 20878?

ZIP code 20878 has an estimated population of 65,954 residents, with a density of 3,225 people per square mile.

What timezone is ZIP code 20878 in?

ZIP code 20878 observes the EST timezone.