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/21912

21912

ZIP 21912 is Warwick, Maryland, mostly in Cecil County; area codes 667 and 410; Eastern time.

Type
Standard
Time zone
America/New_York
County
Cecil +1 more
Population
1,536
Coordinates
39.4194, -75.8186
☼ Live from 21912 — Warwick, MD

Weather right now

Asking the National Weather Service…

NEXRAD radar
Finding the nearest radar…
Local time: —

Where 21912 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 21912
  • 🔢 Type 21912 into a pocket calculator and turn it upside down: ZIGIZ — not quite a word, sorry.
  • ⇆21912 reads the same backwards. It is one of only 412 palindromic ZIP codes.
  • ➕ As a number, 21,912 = 2 × 2 × 2 × 3 × 11 × 83. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101010110011000
  • 🏠 Its numerical neighbours: 21911 (Rising Sun, MD, 22 mi away) and 21913 (Cecilton, MD, 3 mi 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, 2,355 miles away.
  • 🧭 Farther north than 52% of all ZIP codes, and farther east than 85%.
  • 🎯1,208 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21912 and you would come out at 39.42°S, 104.18°E — 833 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 57m of daylight. Shortest: 9h 23m.
  • 📏 At 33.9 square miles of land, 21912 is bigger than 49% of ZIP codes — room for about 26 Central Parks.
🌙 The sky over 21912 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population1,536This ZIP1,536
Households696This ZIP696
Housing units704This ZIP704
Median age58.2This ZIP58.2Maryland39.4US 38.9
Median household income$69,868This ZIP$69,868Maryland$103,678US $80,734
Median home value$391,700This ZIP$391,700Maryland$419,900US $332,700
Median gross rent$817This ZIP$817Maryland$1,705US $1,413
Bachelor's degree or higher25.3%This ZIP25.3%
Mean commute30.8 minThis ZIP30.8 min
Population density45.3 / sq miThis ZIP45.3 / sq mi

Business and tax activity

Business establishments16This ZIP16
Employees73This ZIP73
Annual payroll$2,632,000This ZIP$2,632,000
Tax returns filed540This ZIP540
Total adjusted gross income$56,871,000This ZIP$56,871,000

Land area

Land area33.87 sq miThis ZIP33.87 sq mi
Water area1.75 sq miThis ZIP1.75 sq mi

Counties 21912 spans

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

CountyShare of this ZIP
Cecil County 99.8%
New Castle County 0.2%

Other place names in 21912

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

ZIP codes near 21912

ZIPCityDistance
21913 Cecilton, MD 2.8 mi
21930 Georgetown, MD 5.0 mi
21915 Chesapeake City, MD 5.5 mi
21635 Galena, MD 6.0 mi
21919 Earleville, MD 6.1 mi
21650 Massey, MD 7.5 mi
19730 Odessa, DE 8.8 mi
19709 Middletown, DE 9.1 mi
19734 Townsend, DE 9.2 mi
21645 Kennedyville, MD 10.3 mi

Find every ZIP code within 10 miles of 21912 →

Questions about this ZIP code

Where is ZIP code 21912?

21912 is in Warwick, Maryland, in Cecil County, part of the Philadelphia-Camden-Wilmington, PA-NJ-DE-MD metropolitan area. Its published point location is 39.4194, -75.8186.

What county is 21912 in?

21912 spans 2 counties: Cecil County and New Castle County. Most of it falls in Cecil 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 21912?

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

What time zone is 21912 in?

21912 uses America/New_York.

How many people live in 21912?

About 1,536 people live in ZIP code 21912, in 696 households, at 45.3 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 21912?

$69,868 a year, against $103,678 across Maryland.

What ZIP codes are near 21912?

The closest are 21913 (2.8 mi), 21930 (5 mi), 21915 (5.5 mi), 21635 (6 mi) and 21919 (6.1 mi).

Is 21912 a PO Box ZIP code?

21912 is a standard ZIP code. A normal ZIP code with street delivery.

Download or cite

Cite this page

zipcodes.pro. “21912 ZIP Code — Warwick, Maryland (Cecil County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21912

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/21912.json

Underlying data is public domain or openly licensed — sources, vintages and licences.