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zipcodes.pro — ZIP/21921

21921

ZIP 21921 is in Elkton, Maryland, in Cecil County; area codes 443, 410 and 667; Eastern time. Elkton has 2 ZIP codes; the other is 21922.

Type
Standard
Time zone
America/New_York
County
Cecil
Population
45,527
Coordinates
39.6271, -75.8599
☼ Live from 21921 — Elkton, MD

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Local time: —

Where 21921 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 21921
  • 🔢 Type 21921 into a pocket calculator and turn it upside down: IZGIZ — not quite a word, sorry.
  • ➕ As a number, 21,921 = 3 × 7307. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101010110100001
  • 🏠 Its numerical neighbours: 21920 (Elk Mills, MD, 2 mi away) and 21922 (Elkton, MD, 2 mi away).
  • 🔄 Backwards, 21921 becomes 12912 — and that is a real ZIP code: Au Sable Forks, NY, 352 miles away.
  • 👥 16 other ZIP codes are made of exactly the same digits (11229, 12192, 12912, 12921, 19122, 21219, …). The farthest-flung twin is 91221 in Glendale, CA, 2,351 miles away.
  • 🧭 Farther north than 53% of all ZIP codes, and farther east than 85%.
  • 🎯1,204 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21921 and you would come out at 39.63°S, 104.14°E — 843 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 58m of daylight. Shortest: 9h 22m.
  • 📏 At 94.7 square miles of land, 21921 is bigger than 76% of ZIP codes — room for about 72 Central Parks.
🌙 The sky over 21921 today
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🌋 Shake report
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Source: USGS.

People and housing

Population45,527This ZIP45,527
Households17,316This ZIP17,316
Housing units18,475This ZIP18,475
Median age39.4This ZIP39.4Maryland39.4US 38.9
Median household income$85,775This ZIP$85,775Maryland$103,678US $80,734
Median home value$330,400This ZIP$330,400Maryland$419,900US $332,700
Median gross rent$1,421This ZIP$1,421Maryland$1,705US $1,413
Bachelor's degree or higher28.8%This ZIP28.8%
Mean commute26.9 minThis ZIP26.9 min
Population density480.6 / sq miThis ZIP480.6 / sq mi

Business and tax activity

Business establishments802This ZIP802
Employees15,064This ZIP15,064
Annual payroll$1,021,905,000This ZIP$1,021,905,000
Tax returns filed20,760This ZIP20,760
Total adjusted gross income$1,547,751,000This ZIP$1,547,751,000

Land area

Land area94.73 sq miThis ZIP94.73 sq mi
Water area5.49 sq miThis ZIP5.49 sq mi

Other place names in 21921

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

ZIP codes near 21921

ZIPCityDistance
21916 Childs, MD 1.5 mi
21922 Elkton, MD 2.0 mi
21920 Elk Mills, MD 2.2 mi
21901 North East, MD 6.5 mi
19351 Lewisville, PA 6.6 mi
19716 Newark, DE 6.7 mi
19717 Newark, DE 6.8 mi
19702 Newark, DE 7.0 mi
21914 Charlestown, MD 7.5 mi
19360 New London, PA 7.9 mi

Find every ZIP code within 10 miles of 21921 →

Questions about this ZIP code

Where is ZIP code 21921?

21921 is in Elkton, Maryland, in Cecil County, part of the Philadelphia-Camden-Wilmington, PA-NJ-DE-MD metropolitan area. Its published point location is 39.6271, -75.8599.

What county is 21921 in?

21921 lies in Cecil County.

What area code is 21921?

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

What time zone is 21921 in?

21921 uses America/New_York.

How many people live in 21921?

About 45,527 people live in ZIP code 21921, in 17,316 households, at 480.6 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 21921?

$85,775 a year, against $103,678 across Maryland.

What ZIP codes are near 21921?

The closest are 21916 (1.5 mi), 21922 (2 mi), 21920 (2.2 mi), 21901 (6.5 mi) and 19351 (6.6 mi).

Is 21921 a PO Box ZIP code?

21921 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21921 ZIP Code — Elkton, Maryland (Cecil County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21921

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