Weather right now
Asking the National Weather Service…
Where 21810 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.
- 🔢 Type 21810 into a pocket calculator and turn it upside down: OIBIZ — not quite a word, sorry.
- ➕ As a number, 21,810 = 2 × 3 × 5 × 727. Its digits add up to 12, a total 940 other ZIP codes share.
- 💾In binary, the way a computer stores it:
101010100110010 - 🏠 Its numerical neighbours: 21804 (Salisbury, MD, 9 mi away) and 21811 (Berlin, MD, 25 mi away).
- 🔄 Backwards, 21810 becomes 01812 — and that is a real ZIP code: Andover, MA, 383 miles away.
- 👥 34 other ZIP codes are made of exactly the same digits (01128, 01812, 01821, 02118, 10128, 10281, …). The farthest-flung twin is 81120 in Antonito, CO, 1,669 miles away.
- 🧭 Farther south than 56% of all ZIP codes, and farther east than 86%.
- 🎯1,229 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
- 🌏 Dig straight through the Earth from 21810 and you would come out at 38.29°S, 104.31°E — 785 miles from Perth, Australia, the nearest big city to that spot.
- ☀Longest day of the year: 14h 50m of daylight. Shortest: 9h 30m.
- 📏 At 0.475 square miles of land, 21810 is bigger than 5% of ZIP codes — about 230 football fields.
- Working out the sun…
- Checking the USGS…
Source: USGS.
People and housing
| Population | 55This ZIP55 |
|---|---|
| Households | 21This ZIP21 |
| Housing units | 21This ZIP21 |
| Median age | 69.9This ZIP69.9Maryland39.4US 38.9 |
| Bachelor's degree or higher | 52.7%This ZIP52.7% |
| Population density | 115.8 / sq miThis ZIP115.8 / sq mi |
Land area
| Land area | 0.48 sq miThis ZIP0.48 sq mi |
|---|---|
| Water area | 0.01 sq miThis ZIP0.01 sq mi |
Other place names in 21810
Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.
ZIP codes near 21810
| ZIP | City | Distance |
|---|---|---|
21822 | Eden, MD | 1.5 mi |
21826 | Fruitland, MD | 4.0 mi |
21801 | Salisbury, MD | 4.1 mi |
21853 | Princess Anne, MD | 6.3 mi |
21856 | Quantico, MD | 6.4 mi |
21865 | Tyaskin, MD | 7.5 mi |
21802 | Salisbury, MD | 7.5 mi |
21803 | Salisbury, MD | 7.5 mi |
21830 | Hebron, MD | 7.8 mi |
21804 | Salisbury, MD | 8.7 mi |
Find every ZIP code within 10 miles of 21810 →
Questions about this ZIP code
Where is ZIP code 21810?
21810 is in Allen, Maryland, in Wicomico County, part of the Salisbury, MD metropolitan area. Its published point location is 38.2907, -75.6893.
What county is 21810 in?
21810 lies in Wicomico County.
What area code is 21810?
Allen uses area codes 410, 667 and 443, from NANPA's telephone records.
What time zone is 21810 in?
21810 uses America/New_York.
How many people live in 21810?
About 55 people live in ZIP code 21810, in 21 households, at 115.8 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.
What ZIP codes are near 21810?
The closest are 21822 (1.5 mi), 21826 (4 mi), 21801 (4.1 mi), 21853 (6.3 mi) and 21856 (6.4 mi).
Is 21810 a PO Box ZIP code?
21810 is a standard ZIP code. A normal ZIP code with street delivery.
Download or cite
Cite this page
zipcodes.pro. “21810 ZIP Code — Allen, Maryland (Wicomico County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21810
Machine-readable version of these facts:
curl https://zipcodes.pro/zip/21810.jsonUnderlying data is public domain or openly licensed — sources, vintages and licences.