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zipcodes.pro — ZIP/20878

20878

ZIP 20878 is in Gaithersburg, Maryland, in Montgomery County; area codes 240, 301 and 227; Eastern time. Gaithersburg has 9 ZIP codes in all.

Type
Standard
Time zone
America/New_York
County
Montgomery
Population
66,115
Coordinates
39.1126, -77.2504
☼ Live from 20878 — Gaithersburg, MD

Weather right now

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Local time: —

Where 20878 is

Approximate ZIP boundary (Census ZCTA 2020). ZIP codes are mail routes, not areas, so the shape shown is the Census tabulation area that approximates it.

★ Weird and wonderful facts about 20878
  • 🔢 Type 20878 into a pocket calculator and turn it upside down: BLBOZ — not quite a word, sorry.
  • ➕ As a number, 20,878 = 2 × 11 × 13 × 73. Its digits add up to 25, a total 2,242 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000110001110
  • 🏠 Its numerical neighbours: 20877 (Gaithersburg, MD, 4 mi away) and 20879 (Gaithersburg, MD, 6 mi away).
  • 🔄 Backwards, 20878 becomes 87802, which is not a ZIP code at all.
  • 👥 22 other ZIP codes are made of exactly the same digits (02878, 02887, 07828, 07882, 08827, 08872, …). The farthest-flung twin is 87820 in Aragon, NM, 1,767 miles away.
  • 🧭 Farther south than 50% of all ZIP codes, and farther east than 80%.
  • 🎯1,136 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20878 and you would come out at 39.11°S, 102.75°E — 886 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 55m of daylight. Shortest: 9h 25m.
  • 📏 At 20.4 square miles of land, 20878 is bigger than 38% of ZIP codes — room for about 16 Central Parks.
🌙 The sky over 20878 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population66,115This ZIP66,115
Households24,237This ZIP24,237
Housing units25,127This ZIP25,127
Median age41.4This ZIP41.4Maryland39.4US 38.9
Median household income$144,313This ZIP$144,313Maryland$103,678US $80,734
Median home value$715,800This ZIP$715,800Maryland$419,900US $332,700
Median gross rent$2,226This ZIP$2,226Maryland$1,705US $1,413
Bachelor's degree or higher70.3%This ZIP70.3%
Mean commute29.4 minThis ZIP29.4 min
Population density3,233.2 / sq miThis ZIP3,233.2 / sq mi

Business and tax activity

Business establishments2,087This ZIP2,087
Employees23,732This ZIP23,732
Annual payroll$2,042,731,000This ZIP$2,042,731,000
Tax returns filed33,280This ZIP33,280
Total adjusted gross income$4,557,746,000This ZIP$4,557,746,000

Land area

Land area20.45 sq miThis ZIP20.45 sq mi
Water area0.38 sq miThis ZIP0.38 sq mi

Other place names in 20878

Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.

ZIP codes near 20878

ZIPCityDistance
20899 Gaithersburg, MD 2.9 mi
20874 Germantown, MD 3.1 mi
20813 Bethesda, MD 3.2 mi
20827 Bethesda, MD 3.2 mi
20848 Rockville, MD 3.2 mi
20859 Potomac, MD 3.2 mi
20875 Germantown, MD 3.2 mi
20884 Gaithersburg, MD 3.2 mi
20897 Suburb Maryland Fac, MD 3.2 mi
20898 Gaithersburg, MD 3.2 mi

Find every ZIP code within 10 miles of 20878 →

Questions about this ZIP code

Where is ZIP code 20878?

20878 is in Gaithersburg, Maryland, in Montgomery County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 39.1126, -77.2504.

What county is 20878 in?

20878 lies in Montgomery County.

What area code is 20878?

Gaithersburg uses area codes 240, 301 and 227, from NANPA's telephone records.

What time zone is 20878 in?

20878 uses America/New_York.

How many people live in 20878?

About 66,115 people live in ZIP code 20878, in 24,237 households, at 3,233.2 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What is the median household income in 20878?

$144,313 a year, against $103,678 across Maryland.

What ZIP codes are near 20878?

The closest are 20899 (2.9 mi), 20874 (3.1 mi), 20813 (3.2 mi), 20827 (3.2 mi) and 20848 (3.2 mi).

Is 20878 a PO Box ZIP code?

20878 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20878 ZIP Code — Gaithersburg, Maryland (Montgomery County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20878

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