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zipcodes.pro — ZIP/21837

21837

ZIP 21837 is Mardela Springs, Maryland, in Wicomico County; area codes 410, 443 and 667; Eastern time.

Type
Standard
Time zone
America/New_York
County
Wicomico
Metro area
Salisbury, MD
Population
2,891
Coordinates
38.4546, -75.7663
☼ Live from 21837 — Mardela Springs, MD

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Where 21837 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 21837
  • 🔢 Type 21837 into a pocket calculator and turn it upside down: LEBIZ — not quite a word, sorry.
  • ➕ As a number, 21,837 = 3 × 29 × 251. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101010101001101
  • 🏠 Its numerical neighbours: 21836 (Manokin, MD, 23 mi away) and 21838 (Marion Station, MD, 30 mi away).
  • 🔄 Backwards, 21837 becomes 73812, which is not a ZIP code at all.
  • 👥 56 other ZIP codes are made of exactly the same digits (12738, 12783, 12837, 12873, 13782, 13827, …). The farthest-flung twin is 83712 in Boise, ID, 2,111 miles away.
  • 🧭 Farther south than 55% of all ZIP codes, and farther east than 85%.
  • 🎯1,223 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21837 and you would come out at 38.45°S, 104.23°E — 794 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 51m of daylight. Shortest: 9h 29m.
  • 📏 At 43.9 square miles of land, 21837 is bigger than 56% of ZIP codes — room for about 33 Central Parks.
🌙 The sky over 21837 today
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🌋 Shake report
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Source: USGS.

People and housing

Population2,891This ZIP2,891
Households1,123This ZIP1,123
Housing units1,179This ZIP1,179
Median age40.8This ZIP40.8Maryland39.4US 38.9
Median household income$62,880This ZIP$62,880Maryland$103,678US $80,734
Median home value$227,400This ZIP$227,400Maryland$419,900US $332,700
Median gross rent$1,115This ZIP$1,115Maryland$1,705US $1,413
Bachelor's degree or higher18.0%This ZIP18.0%
Mean commute25.6 minThis ZIP25.6 min
Population density65.9 / sq miThis ZIP65.9 / sq mi

Business and tax activity

Business establishments33This ZIP33
Employees190This ZIP190
Annual payroll$6,829,000This ZIP$6,829,000
Tax returns filed1,220This ZIP1,220
Total adjusted gross income$76,396,000This ZIP$76,396,000

Land area

Land area43.86 sq miThis ZIP43.86 sq mi
Water area3.25 sq miThis ZIP3.25 sq mi

Other place names in 21837

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

ZIP codes near 21837

ZIPCityDistance
21830 Hebron, MD 4.3 mi
21861 Sharptown, MD 6.0 mi
21659 Rhodesdale, MD 8.5 mi
21801 Salisbury, MD 8.7 mi
21856 Quantico, MD 8.7 mi
21802 Salisbury, MD 8.8 mi
21803 Salisbury, MD 8.8 mi
21869 Vienna, MD 9.4 mi
21835 Linkwood, MD 10.7 mi
19940 Delmar, DE 11.0 mi

Find every ZIP code within 10 miles of 21837 →

Questions about this ZIP code

Where is ZIP code 21837?

21837 is in Mardela Springs, Maryland, in Wicomico County, part of the Salisbury, MD metropolitan area. Its published point location is 38.4546, -75.7663.

What county is 21837 in?

21837 lies in Wicomico County.

What area code is 21837?

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

What time zone is 21837 in?

21837 uses America/New_York.

How many people live in 21837?

About 2,891 people live in ZIP code 21837, in 1,123 households, at 65.9 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 21837?

$62,880 a year, against $103,678 across Maryland.

What ZIP codes are near 21837?

The closest are 21830 (4.3 mi), 21861 (6 mi), 21659 (8.5 mi), 21801 (8.7 mi) and 21856 (8.7 mi).

Is 21837 a PO Box ZIP code?

21837 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21837 ZIP Code — Mardela Springs, Maryland (Wicomico County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21837

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