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zipcodes.pro — ZIP/15666

15666

ZIP 15666 is Mount Pleasant, Pennsylvania, mostly in Westmoreland County; area codes 724 and 878; Eastern time.

Type
Standard
Time zone
America/New_York
County
Westmoreland +1 more
Metro area
Pittsburgh, PA
Population
15,980
Coordinates
40.1610, -79.5098
☼ Live from 15666 — Mount Pleasant, PA

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Where 15666 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 15666
  • 🔢 Type 15666 into a pocket calculator and turn it upside down: gggSI — not quite a word, sorry.
  • ➕ As a number, 15,666 = 2 × 3 × 7 × 373. Its digits add up to 24, a total 2,425 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 11110100110010
  • 🏠 Its numerical neighbours: 15665 (Manor, PA, 15 mi away) and 15668 (Murrysville, PA, 23 mi away).
  • 🔄 Backwards, 15666 becomes 66651, which is not a ZIP code at all.
  • 👥 9 other ZIP codes are made of exactly the same digits (16656, 16665, 56166, 56661, 61656, 65616, …). The farthest-flung twin is 56661 in Northome, MN, 897 miles away.
  • 🧭 Farther north than 58% of all ZIP codes, and farther east than 75%.
  • 🎯1,008 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 15666 and you would come out at 40.16°S, 100.49°E — 1,027 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 02m of daylight. Shortest: 9h 18m.
  • 📏 At 53.5 square miles of land, 15666 is bigger than 61% of ZIP codes — room for about 41 Central Parks.
🌙 The sky over 15666 today
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🌋 Shake report
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Source: USGS.

People and housing

Population15,980This ZIP15,980
Households7,308This ZIP7,308
Housing units7,859This ZIP7,859
Median age50.2This ZIP50.2Pennsylvania40.9US 38.9
Median household income$68,102This ZIP$68,102Pennsylvania$77,971US $80,734
Median home value$163,100This ZIP$163,100Pennsylvania$254,500US $332,700
Median gross rent$799This ZIP$799Pennsylvania$1,209US $1,413
Bachelor's degree or higher22.8%This ZIP22.8%
Mean commute26.1 minThis ZIP26.1 min
Population density298.9 / sq miThis ZIP298.9 / sq mi

Business and tax activity

Business establishments421This ZIP421
Employees7,829This ZIP7,829
Annual payroll$446,041,000This ZIP$446,041,000
Tax returns filed7,640This ZIP7,640
Total adjusted gross income$499,073,000This ZIP$499,073,000

Land area

Land area53.46 sq miThis ZIP53.46 sq mi
Water area0.19 sq miThis ZIP0.19 sq mi

Counties 15666 spans

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

CountyShare of this ZIP
Westmoreland County 76.1%
Fayette County 23.9%

Other place names in 15666

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

ZIP codes near 15666

ZIPCityDistance
15674 Norvelt, PA 3.2 mi
15621 Calumet, PA 3.7 mi
15688 Tarrs, PA 4.1 mi
15689 United, PA 4.5 mi
15612 Alverton, PA 5.0 mi
15639 Hunker, PA 5.3 mi
15610 Acme, PA 5.4 mi
15616 Armbrust, PA 5.6 mi
15490 White, PA 6.0 mi
15676 Pleasant Unity, PA 6.3 mi

Find every ZIP code within 10 miles of 15666 →

Questions about this ZIP code

Where is ZIP code 15666?

15666 is in Mount Pleasant, Pennsylvania, in Westmoreland County, part of the Pittsburgh, PA metropolitan area. Its published point location is 40.1610, -79.5098.

What county is 15666 in?

15666 spans 2 counties: Westmoreland County and Fayette County. Most of it falls in Westmoreland 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 15666?

Mount Pleasant uses area codes 724 and 878, from NANPA's telephone records.

What time zone is 15666 in?

15666 uses America/New_York.

How many people live in 15666?

About 15,980 people live in ZIP code 15666, in 7,308 households, at 298.9 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 15666?

$68,102 a year, against $77,971 across Pennsylvania.

What ZIP codes are near 15666?

The closest are 15674 (3.2 mi), 15621 (3.7 mi), 15688 (4.1 mi), 15689 (4.5 mi) and 15612 (5 mi).

Is 15666 a PO Box ZIP code?

15666 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “15666 ZIP Code — Mount Pleasant, Pennsylvania (Westmoreland County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/15666

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