Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — ZIP/20849

20849

ZIP 20849 is in Rockville, Maryland, in Montgomery County; area codes 240, 301 and 227; Eastern time. Rockville has 8 ZIP codes in all.

Type
No street area
Time zone
America/New_York
County
Montgomery
Coordinates
39.0840, -77.1528

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 20850, whose figures describe that area — not this ZIP code.

☼ Live from 20849 — Rockville, MD

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Where 20849 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 20849
  • 🔢 Type 20849 into a pocket calculator and turn it upside down: GhBOZ — not quite a word, sorry.
  • ➕ 20849 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 23, a total 2,533 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000101110001
  • 🏠 Its numerical neighbours: 20848 (Rockville, MD, 5 mi away) and 20850 (Rockville, MD, 2 mi away).
  • 🔄 Backwards, 20849 becomes 94802 — and that is a real ZIP code: Richmond, CA, 2,419 miles away.
  • 👥 51 other ZIP codes are made of exactly the same digits (02894, 04289, 04928, 04982, 09248, 09824, …). The farthest-flung twin is 09824 in APO AE, a military post office, 5,653 miles away.
  • 🧭 Farther south than 50% of all ZIP codes, and farther east than 81%.
  • 🎯1,141 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20849 and you would come out at 39.08°S, 102.85°E — 881 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 55m of daylight. Shortest: 9h 25m.
🌙 The sky over 20849 today
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🌋 Shake report
  • Checking the USGS…

Source: USGS.

Business and tax activity

Business establishments7This ZIP7
Employees18This ZIP18
Annual payroll$528,000This ZIP$528,000

Land area

ZIP codes near 20849

ZIPCityDistance
20847 Rockville, MD 0.0 mi
20857 Rockville, MD 0.0 mi
20883 Gaithersburg, MD 0.4 mi
20850 Rockville, MD 1.5 mi
20851 Rockville, MD 1.8 mi
20852 Rockville, MD 2.7 mi
20853 Rockville, MD 3.4 mi
20855 Derwood, MD 3.8 mi
20880 Washington Grove, MD 4.1 mi
20877 Gaithersburg, MD 4.4 mi

Find every ZIP code within 10 miles of 20849 →

Questions about this ZIP code

Where is ZIP code 20849?

20849 is in Rockville, Maryland, in Montgomery County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 39.0840, -77.1528.

What county is 20849 in?

20849 lies in Montgomery County.

What area code is 20849?

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

What time zone is 20849 in?

20849 uses America/New_York.

What ZIP codes are near 20849?

The closest are 20847 (0 mi), 20857 (0 mi), 20883 (0.4 mi), 20850 (1.5 mi) and 20851 (1.8 mi).

Is 20849 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. “20849 ZIP Code — Rockville, Maryland (Montgomery County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20849

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