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zipcodes.pro — ZIP/21711

21711

ZIP 21711 is Big Pool, Maryland, in Washington County; area codes 240 and 301; Eastern time.

Type
Standard
Time zone
America/New_York
County
Washington
Population
929
Coordinates
39.6684, -78.0196
☼ Live from 21711 — Big Pool, MD

Weather right now

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Local time: —

Where 21711 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 21711
  • 🔢 Type 21711 into a pocket calculator and turn it upside down: IILIZ — not quite a word, sorry.
  • ➕ As a number, 21,711 = 3 × 7237. Its digits add up to 12, a total 940 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101010011001111
  • 🏠 Its numerical neighbours: 21710 (Adamstown, MD, 40 mi away) and 21713 (Boonsboro, MD, 21 mi away).
  • 🔄 Backwards, 21711 becomes 11712, which is not a ZIP code at all.
  • 👥 11 other ZIP codes are made of exactly the same digits (11217, 11721, 12117, 17112, 17121, 17211, …). The farthest-flung twin is 71112 in Bossier City, LA, 1,003 miles away.
  • 🧭 Farther north than 53% of all ZIP codes, and farther east than 79%.
  • 🎯1,090 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21711 and you would come out at 39.67°S, 101.98°E — 941 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 59m of daylight. Shortest: 9h 21m.
  • 📏 At 24.6 square miles of land, 21711 is bigger than 41% of ZIP codes — room for about 19 Central Parks.
🌙 The sky over 21711 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population929This ZIP929
Households434This ZIP434
Housing units448This ZIP448
Median age52.3This ZIP52.3Maryland39.4US 38.9
Median household income$91,250This ZIP$91,250Maryland$103,678US $80,734
Median home value$310,600This ZIP$310,600Maryland$419,900US $332,700
Bachelor's degree or higher20.2%This ZIP20.2%
Mean commute30.5 minThis ZIP30.5 min
Population density37.8 / sq miThis ZIP37.8 / sq mi

Business and tax activity

Business establishments16This ZIP16
Employees145This ZIP145
Annual payroll$7,335,000This ZIP$7,335,000
Tax returns filed500This ZIP500
Total adjusted gross income$33,845,000This ZIP$33,845,000

Land area

Land area24.56 sq miThis ZIP24.56 sq mi
Water area0.68 sq miThis ZIP0.68 sq mi

Other place names in 21711

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

ZIP codes near 21711

ZIPCityDistance
21722 Clear Spring, MD 5.7 mi
25419 Falling Waters, WV 9.3 mi
17236 Mercersburg, PA 9.9 mi
17212 Big Cove Tannery, PA 10.2 mi
25427 Hedgesville, WV 11.1 mi
21750 Hancock, MD 11.5 mi
21795 Williamsport, MD 12.1 mi
25403 Martinsburg, WV 13.4 mi
25411 Berkeley Springs, WV 13.6 mi
25404 Martinsburg, WV 14.0 mi

Find every ZIP code within 10 miles of 21711 →

Questions about this ZIP code

Where is ZIP code 21711?

21711 is in Big Pool, Maryland, in Washington County, part of the Hagerstown-Martinsburg, MD-WV metropolitan area. Its published point location is 39.6684, -78.0196.

What county is 21711 in?

21711 lies in Washington County.

What area code is 21711?

Big Pool uses area codes 240 and 301, from NANPA's telephone records.

What time zone is 21711 in?

21711 uses America/New_York.

How many people live in 21711?

About 929 people live in ZIP code 21711, in 434 households, at 37.8 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 21711?

$91,250 a year, against $103,678 across Maryland.

What ZIP codes are near 21711?

The closest are 21722 (5.7 mi), 25419 (9.3 mi), 17236 (9.9 mi), 17212 (10.2 mi) and 25427 (11.1 mi).

Is 21711 a PO Box ZIP code?

21711 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21711 ZIP Code — Big Pool, Maryland (Washington County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21711

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