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zipcodes.pro — ZIP/20851

20851

ZIP 20851 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
14,946
Coordinates
39.0781, -77.1208
☼ Live from 20851 — Rockville, MD

Weather right now

Asking the National Weather Service…

NEXRAD radar
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Local time: —

Where 20851 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 20851
  • 🔢 Type 20851 into a pocket calculator and turn it upside down: ISBOZ — not quite a word, sorry.
  • ➕ As a number, 20,851 = 29 × 719. Its digits add up to 16, a total 1,922 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000101110011
  • 🏠 Its numerical neighbours: 20850 (Rockville, MD, 3 mi away) and 20852 (Rockville, MD, 2 mi away).
  • 🔄 Backwards, 20851 becomes 15802, which is not a ZIP code at all.
  • 👥 65 other ZIP codes are made of exactly the same digits (01258, 01825, 01852, 02185, 02815, 05821, …). The farthest-flung twin is 85012 in Phoenix, AZ, 1,971 miles away.
  • 🧭 Farther south than 50% of all ZIP codes, and farther east than 81%.
  • 🎯1,143 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20851 and you would come out at 39.08°S, 102.88°E — 879 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 55m of daylight. Shortest: 9h 25m.
  • 📏 At 2.5 square miles of land, 20851 is bigger than 13% of ZIP codes — room for about 1.9 Central Parks.
🌙 The sky over 20851 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population14,946This ZIP14,946
Households5,155This ZIP5,155
Housing units5,338This ZIP5,338
Median age38.6This ZIP38.6Maryland39.4US 38.9
Median household income$126,411This ZIP$126,411Maryland$103,678US $80,734
Median home value$568,900This ZIP$568,900Maryland$419,900US $332,700
Median gross rent$2,043This ZIP$2,043Maryland$1,705US $1,413
Bachelor's degree or higher46.2%This ZIP46.2%
Mean commute31.8 minThis ZIP31.8 min
Population density5,893.5 / sq miThis ZIP5,893.5 / sq mi

Business and tax activity

Business establishments168This ZIP168
Employees1,180This ZIP1,180
Annual payroll$60,712,000This ZIP$60,712,000
Tax returns filed7,570This ZIP7,570
Total adjusted gross income$530,528,000This ZIP$530,528,000

Land area

Land area2.54 sq miThis ZIP2.54 sq mi
Water area0.00 sq mi

Other place names in 20851

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

ZIP codes near 20851

ZIPCityDistance
20847 Rockville, MD 1.8 mi
20849 Rockville, MD 1.8 mi
20857 Rockville, MD 1.8 mi
20852 Rockville, MD 1.8 mi
20883 Gaithersburg, MD 2.1 mi
20853 Rockville, MD 2.2 mi
20896 Garrett Park, MD 3.3 mi
20850 Rockville, MD 3.3 mi
20906 Silver Spring, MD 3.6 mi
20855 Derwood, MD 4.1 mi

Find every ZIP code within 10 miles of 20851 →

Questions about this ZIP code

Where is ZIP code 20851?

20851 is in Rockville, Maryland, in Montgomery County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 39.0781, -77.1208.

What county is 20851 in?

20851 lies in Montgomery County.

What area code is 20851?

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

What time zone is 20851 in?

20851 uses America/New_York.

How many people live in 20851?

About 14,946 people live in ZIP code 20851, in 5,155 households, at 5,893.5 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 20851?

$126,411 a year, against $103,678 across Maryland.

What ZIP codes are near 20851?

The closest are 20847 (1.8 mi), 20849 (1.8 mi), 20857 (1.8 mi), 20852 (1.8 mi) and 20883 (2.1 mi).

Is 20851 a PO Box ZIP code?

20851 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20851 ZIP Code — Rockville, Maryland (Montgomery County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20851

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