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zipcodes.pro — ZIP/20855

20855

ZIP 20855 is Derwood, Maryland, in Montgomery County; area codes 240, 301 and 227; Eastern time.

Type
Standard
Time zone
America/New_York
County
Montgomery
Population
17,279
Coordinates
39.1370, -77.1318
☼ Live from 20855 — Derwood, MD

Weather right now

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NEXRAD radar
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Local time: —

Where 20855 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 20855
  • 🔢 Type 20855 into a pocket calculator and turn it upside down: SSBOZ — not quite a word, sorry.
  • ➕ As a number, 20,855 = 5 × 43 × 97. Its digits add up to 20, a total 2,586 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000101110111
  • 🏠 Its numerical neighbours: 20854 (Potomac, MD, 9 mi away) and 20857 (Rockville, MD, 4 mi away).
  • 🔄 Backwards, 20855 becomes 55802 — and that is a real ZIP code: Duluth, MN, 919 miles away.
  • 👥 25 other ZIP codes are made of exactly the same digits (02558, 05825, 08525, 20585, 25085, 25508, …). The farthest-flung twin is 85025 in Phoenix, AZ, 1,973 miles away.
  • 🧭 Farther north than 50% of all ZIP codes, and farther east than 81%.
  • 🎯1,142 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20855 and you would come out at 39.14°S, 102.87°E — 882 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 55m of daylight. Shortest: 9h 25m.
  • 📏 At 13.1 square miles of land, 20855 is bigger than 31% of ZIP codes — room for about 9.9 Central Parks.
🌙 The sky over 20855 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population17,279This ZIP17,279
Households6,437This ZIP6,437
Housing units6,525This ZIP6,525
Median age41.3This ZIP41.3Maryland39.4US 38.9
Median household income$149,110This ZIP$149,110Maryland$103,678US $80,734
Median home value$640,300This ZIP$640,300Maryland$419,900US $332,700
Median gross rent$2,413This ZIP$2,413Maryland$1,705US $1,413
Bachelor's degree or higher66.8%This ZIP66.8%
Mean commute35.2 minThis ZIP35.2 min
Population density1,321.6 / sq miThis ZIP1,321.6 / sq mi

Business and tax activity

Business establishments480This ZIP480
Employees7,802This ZIP7,802
Annual payroll$493,942,000This ZIP$493,942,000
Tax returns filed8,780This ZIP8,780
Total adjusted gross income$1,132,684,000This ZIP$1,132,684,000

Land area

Land area13.07 sq miThis ZIP13.07 sq mi
Water area0.22 sq miThis ZIP0.22 sq mi

Other place names in 20855

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

ZIP codes near 20855

ZIPCityDistance
20880 Washington Grove, MD 2.3 mi
20879 Gaithersburg, MD 2.7 mi
20832 Olney, MD 3.0 mi
20853 Rockville, MD 3.1 mi
20877 Gaithersburg, MD 3.2 mi
20883 Gaithersburg, MD 3.6 mi
20830 Olney, MD 3.7 mi
20847 Rockville, MD 3.8 mi
20849 Rockville, MD 3.8 mi
20857 Rockville, MD 3.8 mi

Find every ZIP code within 10 miles of 20855 →

Questions about this ZIP code

Where is ZIP code 20855?

20855 is in Derwood, Maryland, in Montgomery County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 39.1370, -77.1318.

What county is 20855 in?

20855 lies in Montgomery County.

What area code is 20855?

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

What time zone is 20855 in?

20855 uses America/New_York.

How many people live in 20855?

About 17,279 people live in ZIP code 20855, in 6,437 households, at 1,321.6 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 20855?

$149,110 a year, against $103,678 across Maryland.

What ZIP codes are near 20855?

The closest are 20880 (2.3 mi), 20879 (2.7 mi), 20832 (3 mi), 20853 (3.1 mi) and 20877 (3.2 mi).

Is 20855 a PO Box ZIP code?

20855 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20855 ZIP Code — Derwood, Maryland (Montgomery County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20855

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