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zipcodes.pro — ZIP/20818

20818

ZIP 20818 is Cabin John, Maryland, in Montgomery County; area codes 240, 301 and 227; Eastern time.

Type
Standard
Time zone
America/New_York
County
Montgomery
Population
1,539
Coordinates
38.9735, -77.1624
☼ Live from 20818 — Cabin John, MD

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Local time: —

Where 20818 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 20818
  • 🔢 Type 20818 into a pocket calculator and turn it upside down: BIBOZ — not quite a word, sorry.
  • ➕ As a number, 20,818 = 2 × 7 × 1487. Its digits add up to 19, a total 2,454 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000101010010
  • 🏠 Its numerical neighbours: 20817 (Bethesda, MD, 2 mi away) and 20824 (Bethesda, MD, 3 mi away).
  • 🔄 Backwards, 20818 becomes 81802, which is not a ZIP code at all.
  • 👥 29 other ZIP codes are made of exactly the same digits (02188, 02818, 02881, 08218, 08812, 08821, …). The farthest-flung twin is 88021 in Anthony, NM, 1,728 miles away.
  • 🧭 Farther south than 51% 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 20818 and you would come out at 38.97°S, 102.84°E — 878 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 54m of daylight. Shortest: 9h 26m.
  • 📏 At 0.928 square miles of land, 20818 is bigger than 8% of ZIP codes — about 449 football fields.
🌙 The sky over 20818 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population1,539This ZIP1,539
Households593This ZIP593
Housing units657This ZIP657
Median age52.7This ZIP52.7Maryland39.4US 38.9
Median household income$245,982This ZIP$245,982Maryland$103,678US $80,734
Median home value$1,335,100This ZIP$1,335,100Maryland$419,900US $332,700
Bachelor's degree or higher86.4%This ZIP86.4%
Mean commute30.1 minThis ZIP30.1 min
Population density1,658.4 / sq miThis ZIP1,658.4 / sq mi

Business and tax activity

Business establishments52This ZIP52
Employees500This ZIP500
Annual payroll$36,588,000This ZIP$36,588,000
Tax returns filed880This ZIP880
Total adjusted gross income$256,867,000This ZIP$256,867,000

Land area

Land area0.93 sq miThis ZIP0.93 sq mi
Water area0.42 sq miThis ZIP0.42 sq mi

Other place names in 20818

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

ZIP codes near 20818

ZIPCityDistance
20812 Glen Echo, MD 1.1 mi
20817 Bethesda, MD 1.7 mi
22101 Mc Lean, VA 2.3 mi
20816 Bethesda, MD 2.5 mi
22106 Mc Lean, VA 2.9 mi
22109 Mc Lean, VA 2.9 mi
22107 Mc Lean, VA 3.1 mi
22108 Mc Lean, VA 3.1 mi
20810 Bethesda, MD 3.3 mi
20811 Bethesda, MD 3.3 mi

Find every ZIP code within 10 miles of 20818 →

Questions about this ZIP code

Where is ZIP code 20818?

20818 is in Cabin John, Maryland, in Montgomery County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 38.9735, -77.1624.

What county is 20818 in?

20818 lies in Montgomery County.

What area code is 20818?

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

What time zone is 20818 in?

20818 uses America/New_York.

How many people live in 20818?

About 1,539 people live in ZIP code 20818, in 593 households, at 1,658.4 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 20818?

$245,982 a year, against $103,678 across Maryland.

What ZIP codes are near 20818?

The closest are 20812 (1.1 mi), 20817 (1.7 mi), 22101 (2.3 mi), 20816 (2.5 mi) and 22106 (2.9 mi).

Is 20818 a PO Box ZIP code?

20818 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20818 ZIP Code — Cabin John, Maryland (Montgomery County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20818

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