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zipcodes.pro — ZIP/21228

21228

ZIP 21228 is Catonsville, Maryland, mostly in Baltimore County; area codes 410, 443 and 667; Eastern time.

Type
Standard
Time zone
America/New_York
County
Baltimore +1 more
Population
50,492
Coordinates
39.2729, -76.7477
☼ Live from 21228 — Catonsville, MD

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Local time: —

Where 21228 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 21228
  • 🔢 Type 21228 into a pocket calculator and turn it upside down: BZZIZ — not quite a word, sorry.
  • ➕ As a number, 21,228 = 2 × 2 × 3 × 29 × 61. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101001011101100
  • 🏠 Its numerical neighbours: 21227 (Halethorpe, MD, 4 mi away) and 21229 (Baltimore, MD, 3 mi away).
  • 🔄 Backwards, 21228 becomes 82212 — and that is a real ZIP code: Fort Laramie, WY, 1,462 miles away.
  • 👥 13 other ZIP codes are made of exactly the same digits (12228, 12822, 18222, 21282, 21822, 22182, …). The farthest-flung twin is 81222 in Coaldale, CO, 1,559 miles away.
  • 🧭 Farther north than 51% of all ZIP codes, and farther east than 83%.
  • 🎯1,161 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21228 and you would come out at 39.27°S, 103.25°E — 869 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 56m of daylight. Shortest: 9h 24m.
  • 📏 At 15.6 square miles of land, 21228 is bigger than 33% of ZIP codes — room for about 12 Central Parks.
🌙 The sky over 21228 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population50,492This ZIP50,492
Households19,788This ZIP19,788
Housing units20,482This ZIP20,482
Median age42.2This ZIP42.2Maryland39.4US 38.9
Median household income$112,656This ZIP$112,656Maryland$103,678US $80,734
Median home value$404,700This ZIP$404,700Maryland$419,900US $332,700
Median gross rent$1,701This ZIP$1,701Maryland$1,705US $1,413
Bachelor's degree or higher52.5%This ZIP52.5%
Mean commute25.4 minThis ZIP25.4 min
Population density3,241.4 / sq miThis ZIP3,241.4 / sq mi

Business and tax activity

Business establishments1,191This ZIP1,191
Employees17,358This ZIP17,358
Annual payroll$1,044,513,000This ZIP$1,044,513,000
Tax returns filed24,610This ZIP24,610
Total adjusted gross income$2,240,222,000This ZIP$2,240,222,000

Land area

Land area15.58 sq miThis ZIP15.58 sq mi
Water area0.04 sq miThis ZIP0.04 sq mi

Counties 21228 spans

A ZIP code is a mail route and ignores county lines. Shares are by overlapping land area.

CountyShare of this ZIP
Baltimore County 99.9%
Baltimore city 0.1%

Other place names in 21228

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

ZIP codes near 21228

ZIPCityDistance
21250 Baltimore, MD 2.3 mi
21043 Ellicott City, MD 3.1 mi
21229 Baltimore, MD 3.1 mi
21207 Gwynn Oak, MD 3.9 mi
21227 Halethorpe, MD 4.3 mi
21244 Windsor Mill, MD 4.6 mi
21075 Elkridge, MD 4.8 mi
21216 Baltimore, MD 4.8 mi
21223 Baltimore, MD 5.1 mi
21215 Baltimore, MD 6.1 mi

Find every ZIP code within 10 miles of 21228 →

Questions about this ZIP code

Where is ZIP code 21228?

21228 is in Catonsville, Maryland, in Baltimore County, part of the Baltimore-Columbia-Towson, MD metropolitan area. Its published point location is 39.2729, -76.7477.

What county is 21228 in?

21228 spans 2 counties: Baltimore County and Baltimore city. Most of it falls in Baltimore County, measured by overlapping land area — the county holding the most land in a ZIP code is not always the one holding the most residents.

What area code is 21228?

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

What time zone is 21228 in?

21228 uses America/New_York.

How many people live in 21228?

About 50,492 people live in ZIP code 21228, in 19,788 households, at 3,241.4 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 21228?

$112,656 a year, against $103,678 across Maryland.

What ZIP codes are near 21228?

The closest are 21250 (2.3 mi), 21043 (3.1 mi), 21229 (3.1 mi), 21207 (3.9 mi) and 21227 (4.3 mi).

Is 21228 a PO Box ZIP code?

21228 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21228 ZIP Code — Catonsville, Maryland (Baltimore County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21228

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