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zipcodes.pro — ZIP/20879

20879

ZIP 20879 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
25,264
Coordinates
39.1673, -77.1641
☼ Live from 20879 — Gaithersburg, MD

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Where 20879 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 20879
  • 🔢 Type 20879 into a pocket calculator and turn it upside down: GLBOZ — not quite a word, sorry.
  • ➕ 20879 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 26, a total 2,038 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000110001111
  • 🏠 Its numerical neighbours: 20878 (Gaithersburg, MD, 6 mi away) and 20880 (Washington Grove, MD, 2 mi away).
  • 🔄 Backwards, 20879 becomes 97802, which is not a ZIP code at all.
  • 👥 41 other ZIP codes are made of exactly the same digits (02879, 07829, 07928, 09728, 09827, 20897, …). The farthest-flung twin is 09827 in APO AE, a military post office, 5,209 miles away.
  • 🧭 Farther north than 50% of all ZIP codes, and farther east than 81%.
  • 🎯1,140 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20879 and you would come out at 39.17°S, 102.84°E — 884 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 56m of daylight. Shortest: 9h 25m.
  • 📏 At 8.6 square miles of land, 20879 is bigger than 25% of ZIP codes — room for about 6.5 Central Parks.
🌙 The sky over 20879 today
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🌋 Shake report
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Source: USGS.

People and housing

Population25,264This ZIP25,264
Households8,651This ZIP8,651
Housing units8,818This ZIP8,818
Median age36.4This ZIP36.4Maryland39.4US 38.9
Median household income$112,104This ZIP$112,104Maryland$103,678US $80,734
Median home value$468,100This ZIP$468,100Maryland$419,900US $332,700
Median gross rent$1,942This ZIP$1,942Maryland$1,705US $1,413
Bachelor's degree or higher44.8%This ZIP44.8%
Mean commute31.3 minThis ZIP31.3 min
Population density2,931.5 / sq miThis ZIP2,931.5 / sq mi

Business and tax activity

Business establishments961This ZIP961
Employees16,628This ZIP16,628
Annual payroll$1,208,263,000This ZIP$1,208,263,000
Tax returns filed14,110This ZIP14,110
Total adjusted gross income$1,004,243,000This ZIP$1,004,243,000

Land area

Land area8.62 sq miThis ZIP8.62 sq mi
Water area0.05 sq miThis ZIP0.05 sq mi

Other place names in 20879

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

ZIP codes near 20879

ZIPCityDistance
20880 Washington Grove, MD 1.9 mi
20877 Gaithersburg, MD 2.4 mi
20885 Gaithersburg, MD 2.5 mi
20886 Montgomery Village, MD 2.6 mi
20855 Derwood, MD 2.7 mi
20813 Bethesda, MD 2.8 mi
20827 Bethesda, MD 2.8 mi
20848 Rockville, MD 2.8 mi
20859 Potomac, MD 2.8 mi
20875 Germantown, MD 2.8 mi

Find every ZIP code within 10 miles of 20879 →

Questions about this ZIP code

Where is ZIP code 20879?

20879 is in Gaithersburg, Maryland, in Montgomery County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 39.1673, -77.1641.

What county is 20879 in?

20879 lies in Montgomery County.

What area code is 20879?

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

What time zone is 20879 in?

20879 uses America/New_York.

How many people live in 20879?

About 25,264 people live in ZIP code 20879, in 8,651 households, at 2,931.5 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 20879?

$112,104 a year, against $103,678 across Maryland.

What ZIP codes are near 20879?

The closest are 20880 (1.9 mi), 20877 (2.4 mi), 20885 (2.5 mi), 20886 (2.6 mi) and 20855 (2.7 mi).

Is 20879 a PO Box ZIP code?

20879 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20879 ZIP Code — Gaithersburg, Maryland (Montgomery County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20879

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