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zipcodes.pro — ZIP/21157

21157

ZIP 21157 is in Westminster, Maryland, in Carroll County; area codes 443, 410 and 667; Eastern time. Westminster has 2 ZIP codes; the other is 21158.

Type
Standard
Time zone
America/New_York
County
Carroll
Population
38,984
Coordinates
39.5486, -76.9836
☼ Live from 21157 — Westminster, MD

Weather right now

Asking the National Weather Service…

NEXRAD radar
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Local time: —

Where 21157 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 21157
  • 🔢 Type 21157 into a pocket calculator and turn it upside down: LSIIZ — not quite a word, sorry.
  • ➕ 21157 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 16, a total 1,922 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101001010100101
  • 🏠 Its numerical neighbours: 21156 (Upper Falls, MD, 32 mi away) and 21158 (Westminster, MD, 8 mi away).
  • 🔄 Backwards, 21157 becomes 75112, which is not a ZIP code at all.
  • 👥 27 other ZIP codes are made of exactly the same digits (11572, 11725, 11752, 12157, 12175, 12517, …). The farthest-flung twin is 75211 in Dallas, TX, 1,204 miles away.
  • 🧭 Farther north than 53% of all ZIP codes, and farther east than 82%.
  • 🎯1,146 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21157 and you would come out at 39.55°S, 103.02°E — 890 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 58m of daylight. Shortest: 9h 22m.
  • 📏 At 77.7 square miles of land, 21157 is bigger than 72% of ZIP codes — room for about 59 Central Parks.
🌙 The sky over 21157 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population38,984This ZIP38,984
Households14,785This ZIP14,785
Housing units15,471This ZIP15,471
Median age43.2This ZIP43.2Maryland39.4US 38.9
Median household income$104,966This ZIP$104,966Maryland$103,678US $80,734
Median home value$424,100This ZIP$424,100Maryland$419,900US $332,700
Median gross rent$1,331This ZIP$1,331Maryland$1,705US $1,413
Bachelor's degree or higher37.9%This ZIP37.9%
Mean commute31.0 minThis ZIP31.0 min
Population density501.8 / sq miThis ZIP501.8 / sq mi

Business and tax activity

Business establishments1,303This ZIP1,303
Employees20,132This ZIP20,132
Annual payroll$1,064,700,000This ZIP$1,064,700,000
Tax returns filed18,660This ZIP18,660
Total adjusted gross income$1,701,472,000This ZIP$1,701,472,000

Land area

Land area77.69 sq miThis ZIP77.69 sq mi
Water area0.15 sq miThis ZIP0.15 sq mi

Other place names in 21157

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

ZIP codes near 21157

ZIPCityDistance
21048 Finksburg, MD 4.6 mi
21776 New Windsor, MD 6.5 mi
21158 Westminster, MD 7.8 mi
21074 Hampstead, MD 9.2 mi
21155 Upperco, MD 9.6 mi
21020 Boring, MD 9.7 mi
21784 Sykesville, MD 10.2 mi
21071 Glyndon, MD 10.3 mi
21136 Reisterstown, MD 10.6 mi
21791 Union Bridge, MD 11.0 mi

Find every ZIP code within 10 miles of 21157 →

Questions about this ZIP code

Where is ZIP code 21157?

21157 is in Westminster, Maryland, in Carroll County, part of the Baltimore-Columbia-Towson, MD metropolitan area. Its published point location is 39.5486, -76.9836.

What county is 21157 in?

21157 lies in Carroll County.

What area code is 21157?

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

What time zone is 21157 in?

21157 uses America/New_York.

How many people live in 21157?

About 38,984 people live in ZIP code 21157, in 14,785 households, at 501.8 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 21157?

$104,966 a year, against $103,678 across Maryland.

What ZIP codes are near 21157?

The closest are 21048 (4.6 mi), 21776 (6.5 mi), 21158 (7.8 mi), 21074 (9.2 mi) and 21155 (9.6 mi).

Is 21157 a PO Box ZIP code?

21157 is a standard ZIP code. A normal ZIP code with street delivery.

Download or cite

Cite this page

zipcodes.pro. “21157 ZIP Code — Westminster, Maryland (Carroll County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21157

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