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zipcodes.pro — ZIP/20871

20871

ZIP 20871 is Clarksburg, Maryland, mostly in Montgomery County; area codes 240, 301 and 227; Eastern time.

Type
Standard
Time zone
America/New_York
County
Montgomery +1 more
Population
30,182
Coordinates
39.2589, -77.2818
☼ Live from 20871 — Clarksburg, MD

Weather right now

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Local time: —

Where 20871 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 20871
  • 🔢 Type 20871 into a pocket calculator and turn it upside down: ILBOZ — not quite a word, sorry.
  • ➕ As a number, 20,871 = 3 × 3 × 3 × 773. Its digits add up to 18, a total 2,332 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000110000111
  • 🏠 Its numerical neighbours: 20868 (Spencerville, MD, 19 mi away) and 20872 (Damascus, MD, 5 mi away).
  • 🔄 Backwards, 20871 becomes 17802, which is not a ZIP code at all.
  • 👥 67 other ZIP codes are made of exactly the same digits (01827, 02187, 02718, 02817, 02871, 07821, …). The farthest-flung twin is 87021 in Milan, NM, 1,698 miles away.
  • 🧭 Farther north than 51% of all ZIP codes, and farther east than 80%.
  • 🎯1,133 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20871 and you would come out at 39.26°S, 102.72°E — 893 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 56m of daylight. Shortest: 9h 24m.
  • 📏 At 22.9 square miles of land, 20871 is bigger than 40% of ZIP codes — room for about 17 Central Parks.
🌙 The sky over 20871 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population30,182This ZIP30,182
Households9,347This ZIP9,347
Housing units9,405This ZIP9,405
Median age37.7This ZIP37.7Maryland39.4US 38.9
Median household income$177,523This ZIP$177,523Maryland$103,678US $80,734
Median home value$668,800This ZIP$668,800Maryland$419,900US $332,700
Median gross rent$2,560This ZIP$2,560Maryland$1,705US $1,413
Bachelor's degree or higher68.1%This ZIP68.1%
Mean commute34.8 minThis ZIP34.8 min
Population density1,319.3 / sq miThis ZIP1,319.3 / sq mi

Business and tax activity

Business establishments544This ZIP544
Employees4,656This ZIP4,656
Annual payroll$326,872,000This ZIP$326,872,000
Tax returns filed13,770This ZIP13,770
Total adjusted gross income$1,709,995,000This ZIP$1,709,995,000

Land area

Land area22.88 sq miThis ZIP22.88 sq mi
Water area0.04 sq miThis ZIP0.04 sq mi

Counties 20871 spans

A ZIP code is a mail route and ignores county lines. Shares are by overlapping land area.

CountyShare of this ZIP
Montgomery County 94.4%
Frederick County 5.6%

Other place names in 20871

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

ZIP codes near 20871

ZIPCityDistance
20876 Germantown, MD 4.4 mi
20872 Damascus, MD 4.9 mi
20838 Barnesville, MD 5.3 mi
21754 Ijamsville, MD 5.4 mi
20841 Boyds, MD 5.7 mi
20886 Montgomery Village, MD 6.4 mi
21770 Monrovia, MD 6.5 mi
20885 Gaithersburg, MD 6.5 mi
20882 Gaithersburg, MD 6.7 mi
20842 Dickerson, MD 8.2 mi

Find every ZIP code within 10 miles of 20871 →

Questions about this ZIP code

Where is ZIP code 20871?

20871 is in Clarksburg, Maryland, in Montgomery County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 39.2589, -77.2818.

What county is 20871 in?

20871 spans 2 counties: Montgomery County and Frederick County. Most of it falls in Montgomery County, measured by overlapping land area — the county holding the most land in a ZIP code is not always the one holding the most residents.

What area code is 20871?

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

What time zone is 20871 in?

20871 uses America/New_York.

How many people live in 20871?

About 30,182 people live in ZIP code 20871, in 9,347 households, at 1,319.3 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 20871?

$177,523 a year, against $103,678 across Maryland.

What ZIP codes are near 20871?

The closest are 20876 (4.4 mi), 20872 (4.9 mi), 20838 (5.3 mi), 21754 (5.4 mi) and 20841 (5.7 mi).

Is 20871 a PO Box ZIP code?

20871 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20871 ZIP Code — Clarksburg, Maryland (Montgomery County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20871

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