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zipcodes.pro — ZIP/21403

21403

ZIP 21403 is in Annapolis, Maryland, in Anne Arundel County; area codes 443, 410 and 667; Eastern time. Annapolis has 8 ZIP codes in all.

Type
Standard
Time zone
America/New_York
County
Anne Arundel
Population
32,681
Coordinates
38.9421, -76.4896
☼ Live from 21403 — Annapolis, MD

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Where 21403 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 21403
  • 🔢 Type 21403 into a pocket calculator and turn it upside down: EOhIZ — not quite a word, sorry.
  • ➕ As a number, 21,403 = 17 × 1259. Its digits add up to 10, a total 513 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101001110011011
  • 🏠 Its numerical neighbours: 21402 (Annapolis, MD, 3 mi away) and 21404 (Annapolis, MD, 3 mi away).
  • 🔄 Backwards, 21403 becomes 30412 — and that is a real ZIP code: Alston, GA, 581 miles away.
  • 👥 68 other ZIP codes are made of exactly the same digits (01243, 01342, 01432, 02134, 02143, 02341, …). The farthest-flung twin is 34021 in APO AA, a military post office, 1,947 miles away.
  • 🧭 Farther south than 51% of all ZIP codes, and farther east than 83%.
  • 🎯1,178 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21403 and you would come out at 38.94°S, 103.51°E — 845 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 54m of daylight. Shortest: 9h 26m.
  • 📏 At 9.3 square miles of land, 21403 is bigger than 26% of ZIP codes — room for about 7.0 Central Parks.
🌙 The sky over 21403 today
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🌋 Shake report
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Source: USGS.

People and housing

Population32,681This ZIP32,681
Households14,359This ZIP14,359
Housing units15,460This ZIP15,460
Median age45.3This ZIP45.3Maryland39.4US 38.9
Median household income$123,329This ZIP$123,329Maryland$103,678US $80,734
Median home value$582,500This ZIP$582,500Maryland$419,900US $332,700
Median gross rent$1,942This ZIP$1,942Maryland$1,705US $1,413
Bachelor's degree or higher56.4%This ZIP56.4%
Mean commute31.4 minThis ZIP31.4 min
Population density3,526.2 / sq miThis ZIP3,526.2 / sq mi

Business and tax activity

Business establishments678This ZIP678
Employees6,546This ZIP6,546
Annual payroll$388,715,000This ZIP$388,715,000
Tax returns filed16,830This ZIP16,830
Total adjusted gross income$2,326,609,000This ZIP$2,326,609,000

Land area

Land area9.27 sq miThis ZIP9.27 sq mi
Water area4.76 sq miThis ZIP4.76 sq mi

Other place names in 21403

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

ZIP codes near 21403

ZIPCityDistance
21404 Annapolis, MD 2.5 mi
21037 Edgewater, MD 3.3 mi
21402 Annapolis, MD 3.4 mi
21106 Mayo, MD 4.0 mi
21401 Annapolis, MD 4.6 mi
21140 Riva, MD 5.3 mi
21409 Annapolis, MD 5.8 mi
21062 Glen Burnie, MD 6.1 mi
21123 Pasadena, MD 6.1 mi
21411 Annapolis, MD 6.1 mi

Find every ZIP code within 10 miles of 21403 →

Questions about this ZIP code

Where is ZIP code 21403?

21403 is in Annapolis, Maryland, in Anne Arundel County, part of the Baltimore-Columbia-Towson, MD metropolitan area. Its published point location is 38.9421, -76.4896.

What county is 21403 in?

21403 lies in Anne Arundel County.

What area code is 21403?

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

What time zone is 21403 in?

21403 uses America/New_York.

How many people live in 21403?

About 32,681 people live in ZIP code 21403, in 14,359 households, at 3,526.2 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 21403?

$123,329 a year, against $103,678 across Maryland.

What ZIP codes are near 21403?

The closest are 21404 (2.5 mi), 21037 (3.3 mi), 21402 (3.4 mi), 21106 (4 mi) and 21401 (4.6 mi).

Is 21403 a PO Box ZIP code?

21403 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21403 ZIP Code — Annapolis, Maryland (Anne Arundel County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21403

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