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/21020

21020

ZIP 21020 is Boring, Maryland, in Baltimore County; area codes 410, 443 and 667; Eastern time.

Type
No street area
Time zone
America/New_York
County
Baltimore
Coordinates
39.5213, -76.8047

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 21136, whose figures describe that area — not this ZIP code.

☼ Live from 21020 — Boring, MD

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Where 21020 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 21020
  • 🔢 Type 21020 into a pocket calculator and turn it upside down: OZOIZ — not quite a word, sorry.
  • ➕ As a number, 21,020 = 2 × 2 × 5 × 1051. Its digits add up to 5, a total 55 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101001000011100
  • 🏠 Its numerical neighbours: 21018 (Benson, MD, 22 mi away) and 21022 (Brooklandville, MD, 11 mi away).
  • 🔄 Backwards, 21020 becomes 02012, which is not a ZIP code at all.
  • 👥 14 other ZIP codes are made of exactly the same digits (01022, 01202, 01220, 02021, 02120, 02201, …). The farthest-flung twin is 02210 in Boston, MA, 359 miles away.
  • 🧭 Farther north than 52% of all ZIP codes, and farther east than 82%.
  • 🎯1,155 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21020 and you would come out at 39.52°S, 103.20°E — 881 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 58m of daylight. Shortest: 9h 22m.
🌙 The sky over 21020 today
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🌋 Shake report
  • Checking the USGS…

Source: USGS.

Land area

ZIP codes near 21020

ZIPCityDistance
21071 Glyndon, MD 2.6 mi
21023 Butler, MD 3.4 mi
21155 Upperco, MD 3.6 mi
21030 Cockeysville, MD 5.7 mi
21136 Reisterstown, MD 6.1 mi
21048 Finksburg, MD 6.5 mi
21117 Owings Mills, MD 6.7 mi
21152 Sparks Glencoe, MD 6.7 mi
21074 Hampstead, MD 7.2 mi
21031 Hunt Valley, MD 8.2 mi

Find every ZIP code within 10 miles of 21020 →

Questions about this ZIP code

Where is ZIP code 21020?

21020 is in Boring, Maryland, in Baltimore County, part of the Baltimore-Columbia-Towson, MD metropolitan area. Its published point location is 39.5213, -76.8047.

What county is 21020 in?

21020 lies in Baltimore County.

What area code is 21020?

Boring uses area codes 410, 443 and 667, from NANPA's telephone records.

What time zone is 21020 in?

21020 uses America/New_York.

What ZIP codes are near 21020?

The closest are 21071 (2.6 mi), 21023 (3.4 mi), 21155 (3.6 mi), 21030 (5.7 mi) and 21136 (6.1 mi).

Is 21020 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.

Download or cite

Cite this page

zipcodes.pro. “21020 ZIP Code — Boring, Maryland (Baltimore County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21020

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/21020.json

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