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ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — ZIP/20850

20850

ZIP 20850 is in Rockville, Maryland, in Montgomery County; area codes 240, 301 and 227; Eastern time. Rockville has 8 ZIP codes in all.

Type
Standard
Time zone
America/New_York
County
Montgomery
Population
50,353
Coordinates
39.0892, -77.1804
☼ Live from 20850 — Rockville, MD

Weather right now

Asking the National Weather Service…

NEXRAD radar
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Local time: —

Where 20850 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 20850
  • 🔢 Type 20850 into a pocket calculator and turn it upside down: OSBOZ — not quite a word, sorry.
  • ➕ As a number, 20,850 = 2 × 3 × 5 × 5 × 139. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000101110010
  • 🏠 Its numerical neighbours: 20849 (Rockville, MD, 2 mi away) and 20851 (Rockville, MD, 3 mi away).
  • 🔄 Backwards, 20850 becomes 05802, which is not a ZIP code at all.
  • 👥 23 other ZIP codes are made of exactly the same digits (05820, 08025, 08052, 08205, 08250, 08502, …). The farthest-flung twin is 85002 in Phoenix, AZ, 1,970 miles away.
  • 🧭 Farther south 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 20850 and you would come out at 39.09°S, 102.82°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 14.1 square miles of land, 20850 is bigger than 32% of ZIP codes — room for about 11 Central Parks.
🌙 The sky over 20850 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population50,353This ZIP50,353
Households21,159This ZIP21,159
Housing units22,418This ZIP22,418
Median age41.2This ZIP41.2Maryland39.4US 38.9
Median household income$125,950This ZIP$125,950Maryland$103,678US $80,734
Median home value$714,400This ZIP$714,400Maryland$419,900US $332,700
Median gross rent$2,309This ZIP$2,309Maryland$1,705US $1,413
Bachelor's degree or higher67.5%This ZIP67.5%
Mean commute30.1 minThis ZIP30.1 min
Population density3,566.6 / sq miThis ZIP3,566.6 / sq mi

Business and tax activity

Business establishments2,728This ZIP2,728
Employees61,746This ZIP61,746
Annual payroll$6,310,440,000This ZIP$6,310,440,000
Tax returns filed25,850This ZIP25,850
Total adjusted gross income$3,588,815,000This ZIP$3,588,815,000

Land area

Land area14.12 sq miThis ZIP14.12 sq mi
Water area0.06 sq miThis ZIP0.06 sq mi

Other place names in 20850

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

ZIP codes near 20850

ZIPCityDistance
20883 Gaithersburg, MD 1.3 mi
20847 Rockville, MD 1.5 mi
20849 Rockville, MD 1.5 mi
20857 Rockville, MD 1.5 mi
20851 Rockville, MD 3.3 mi
20880 Washington Grove, MD 3.6 mi
20877 Gaithersburg, MD 3.6 mi
20852 Rockville, MD 4.0 mi
20813 Bethesda, MD 4.1 mi
20827 Bethesda, MD 4.1 mi

Find every ZIP code within 10 miles of 20850 →

Questions about this ZIP code

Where is ZIP code 20850?

20850 is in Rockville, Maryland, in Montgomery County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 39.0892, -77.1804.

What county is 20850 in?

20850 lies in Montgomery County.

What area code is 20850?

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

What time zone is 20850 in?

20850 uses America/New_York.

How many people live in 20850?

About 50,353 people live in ZIP code 20850, in 21,159 households, at 3,566.6 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 20850?

$125,950 a year, against $103,678 across Maryland.

What ZIP codes are near 20850?

The closest are 20883 (1.3 mi), 20847 (1.5 mi), 20849 (1.5 mi), 20857 (1.5 mi) and 20851 (3.3 mi).

Is 20850 a PO Box ZIP code?

20850 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20850 ZIP Code — Rockville, Maryland (Montgomery County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20850

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