21150

ZIP 21150 is Simpsonville, Maryland, in Howard County; area codes 410, 443 and 667; Eastern time.

Type: No street area
Time zone: America/New_York
County: Howard
Metro area: Baltimore-Columbia-Towson, MD
Coordinates: 39.2364, -76.9419

The Census map gives this ZIP code no delivery area of its own, which usually means it serves post office boxes, a single organization or a post office rather than streets of homes.

This ZIP code has no Census tabulation area of its own. Its point falls inside ZCTA 21042, whose figures describe that area — not this ZIP code.

☼ Live from 21150 — Simpsonville, MD

Weather right now

Asking the National Weather Service…

NEXRAD radar

Finding the nearest radar…

Local time: —

Where 21150 is

Loading map… Open 21150 on OpenStreetMap

This ZIP code has no Census tabulation area, so there is no boundary to draw — the marker is its published point location.

★ Weird and wonderful facts about 21150

🔢 Type 21150 into a pocket calculator and turn it upside down: OSIIZ — not quite a word, sorry.
➕ As a number, 21,150 = 2 × 3 × 3 × 5 × 5 × 47. Its digits add up to 9, a total 375 other ZIP codes share.
💾In binary, the way a computer stores it: 101001010011110
🏠 Its numerical neighbours: 21146 (Severna Park, MD, 23 mi away) and 21152 (Sparks Glencoe, MD, 26 mi away).
🔄 Backwards, 21150 becomes 05112, which is not a ZIP code at all.
👥 37 other ZIP codes are made of exactly the same digits (01152, 01521, 02115, 02151, 10125, 10152, …). The farthest-flung twin is 51102 in Sioux City, IA, 1,034 miles away.
🧭 Farther north than 50% of all ZIP codes, and farther east than 82%.
🎯1,151 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
🌏 Dig straight through the Earth from 21150 and you would come out at 39.24°S, 103.06°E — 876 miles from Perth, Australia, the nearest big city to that spot.
☀Longest day of the year: 14h 56m of daylight. Shortest: 9h 24m.

🌙 The sky over 21150 today

Working out the sun…

🌋 Shake report

Checking the USGS…

Source: USGS.

Land area

ZIP codes near 21150

ZIP	City	Distance
`21041`	Ellicott City, MD	0.0 mi
`21029`	Clarksville, MD	1.8 mi
`21036`	Dayton, MD	3.5 mi
`21042`	Ellicott City, MD	3.8 mi
`21044`	Columbia, MD	4.0 mi
`21794`	West Friendship, MD	4.5 mi
`20777`	Highland, MD	4.5 mi
`21737`	Glenelg, MD	4.6 mi
`21738`	Glenwood, MD	5.4 mi
`20862`	Brinklow, MD	5.6 mi

Find every ZIP code within 10 miles of 21150 →

Questions about this ZIP code

Where is ZIP code 21150?

21150 is in Simpsonville, Maryland, in Howard County, part of the Baltimore-Columbia-Towson, MD metropolitan area. Its published point location is 39.2364, -76.9419.

What county is 21150 in?

21150 lies in Howard County.

What area code is 21150?

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

What time zone is 21150 in?

21150 uses America/New_York.

What ZIP codes are near 21150?

The closest are 21041 (0 mi), 21029 (1.8 mi), 21036 (3.5 mi), 21042 (3.8 mi) and 21044 (4 mi).

Is 21150 a PO Box ZIP code?

Possibly. The Census map gives this ZIP code no delivery area of its own, which usually means it serves post office boxes, a single organization or a post office rather than streets of homes.

Download or cite

Cite this page

zipcodes.pro. “21150 ZIP Code — Simpsonville, Maryland (Howard County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21150

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/21150.json

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