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zipcodes.pro — ZIP/20643

20643

ZIP 20643 is Ironsides, Maryland, in Charles County; area codes 240 and 301; Eastern time.

Type
No street area
Time zone
America/New_York
County
Charles
Coordinates
38.5039, -77.1483

The Census map gives this ZIP code no delivery area of its own, which usually means it serves post office boxes, a single organization or a post office rather than streets of homes.

This ZIP code has no Census tabulation area of its own. Its point falls inside ZCTA 20646, whose figures describe that area — not this ZIP code.

☼ Live from 20643 — Ironsides, MD

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Where 20643 is

This ZIP code has no Census tabulation area, so there is no boundary to draw — the marker is its published point location.

★ Weird and wonderful facts about 20643
  • 🔢 Type 20643 into a pocket calculator and turn it upside down: EhgOZ — not quite a word, sorry.
  • ➕ As a number, 20,643 = 3 × 7 × 983. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000010100011
  • 🏠 Its numerical neighbours: 20640 (Indian Head, MD, 3 mi away) and 20645 (Issue, MD, 19 mi away).
  • 🔄 Backwards, 20643 becomes 34602 — and that is a real ZIP code: Brooksville, FL, 751 miles away.
  • 👥 63 other ZIP codes are made of exactly the same digits (02346, 02364, 02634, 02643, 03246, 03264, …). The farthest-flung twin is 34260 in Manasota, FL, 824 miles away.
  • 🧭 Farther south than 55% of all ZIP codes, and farther east than 81%.
  • 🎯1,149 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20643 and you would come out at 38.50°S, 102.85°E — 861 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 51m of daylight. Shortest: 9h 28m.
🌙 The sky over 20643 today
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Source: USGS.

Land area

ZIP codes near 20643

ZIPCityDistance
20640 Indian Head, MD 3.3 mi
20693 Welcome, MD 4.5 mi
20658 Marbury, MD 4.6 mi
20662 Nanjemoy, MD 6.1 mi
20677 Port Tobacco, MD 6.1 mi
22135 Quantico, VA 8.0 mi
20646 La Plata, MD 8.1 mi
22026 Dumfries, VA 8.9 mi
20604 Waldorf, MD 9.0 mi
20675 Pomfret, MD 9.1 mi

Find every ZIP code within 10 miles of 20643 →

Questions about this ZIP code

Where is ZIP code 20643?

20643 is in Ironsides, Maryland, in Charles County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 38.5039, -77.1483.

What county is 20643 in?

20643 lies in Charles County.

What area code is 20643?

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

What time zone is 20643 in?

20643 uses America/New_York.

What ZIP codes are near 20643?

The closest are 20640 (3.3 mi), 20693 (4.5 mi), 20658 (4.6 mi), 20662 (6.1 mi) and 20677 (6.1 mi).

Is 20643 a PO Box ZIP code?

Possibly. The Census map gives this ZIP code no delivery area of its own, which usually means it serves post office boxes, a single organization or a post office rather than streets of homes.

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Cite this page

zipcodes.pro. “20643 ZIP Code — Ironsides, Maryland (Charles County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20643

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/20643.json

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