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zipcodes.pro — ZIP/11721

11721

ZIP 11721 is Centerport, New York, in Suffolk County; area codes 631 and 934; Eastern time.

Type
Standard
Time zone
America/New_York
County
Suffolk
Population
6,426
Coordinates
40.9024, -73.3714
☼ Live from 11721 — Centerport, NY

Weather right now

Asking the National Weather Service…

NEXRAD radar
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Local time: —

Where 11721 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 11721
  • 🔢 Type 11721 into a pocket calculator and turn it upside down: IZLII — not quite a word, sorry.
  • ➕ As a number, 11,721 = 3 × 3907. Its digits add up to 12, a total 940 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10110111001001
  • 🏠 Its numerical neighbours: 11720 (Centereach, NY, 15 mi away) and 11722 (Central Islip, NY, 12 mi away).
  • 🔄 Backwards, 11721 becomes 12711, which is not a ZIP code at all.
  • 👥 11 other ZIP codes are made of exactly the same digits (11217, 12117, 17112, 17121, 17211, 21117, …). The farthest-flung twin is 71112 in Bossier City, LA, 1,262 miles away.
  • 🧭 Farther north than 66% of all ZIP codes, and farther east than 92%.
  • 🎯1,325 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 11721 and you would come out at 40.90°S, 106.63°E — 803 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 07m of daylight. Shortest: 9h 14m.
  • 📏 At 2.5 square miles of land, 11721 is bigger than 13% of ZIP codes — room for about 1.9 Central Parks.
🌙 The sky over 11721 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population6,426This ZIP6,426
Households2,417This ZIP2,417
Housing units2,484This ZIP2,484
Median age50.2This ZIP50.2New York39.8US 38.9
Median household income$197,179This ZIP$197,179New York$85,974US $80,734
Median home value$740,300This ZIP$740,300New York$423,800US $332,700
Median gross rent$3,500+This ZIP$3,500+New York$1,621US $1,413
Bachelor's degree or higher71.4%This ZIP71.4%
Mean commute35.3 minThis ZIP35.3 min
Population density2,561.2 / sq miThis ZIP2,561.2 / sq mi

Business and tax activity

Business establishments175This ZIP175
Employees735This ZIP735
Annual payroll$41,742,000This ZIP$41,742,000
Tax returns filed3,410This ZIP3,410
Total adjusted gross income$686,140,000This ZIP$686,140,000

Land area

Land area2.51 sq miThis ZIP2.51 sq mi
Water area1.44 sq miThis ZIP1.44 sq mi

Other place names in 11721

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

ZIP codes near 11721

ZIPCityDistance
11768 Northport, NY 2.2 mi
11740 Greenlawn, NY 2.6 mi
11743 Huntington, NY 3.0 mi
11731 East Northport, NY 4.0 mi
11724 Cold Spring Harbor, NY 5.2 mi
11746 Huntington Station, NY 6.1 mi
11725 Commack, NY 6.4 mi
11754 Kings Park, NY 6.5 mi
11797 Woodbury, NY 7.8 mi
11760 Melville, NY 7.9 mi

Find every ZIP code within 10 miles of 11721 →

Questions about this ZIP code

Where is ZIP code 11721?

11721 is in Centerport, New York, in Suffolk County, part of the New York-Newark-Jersey City, NY-NJ metropolitan area. Its published point location is 40.9024, -73.3714.

What county is 11721 in?

11721 lies in Suffolk County.

What area code is 11721?

Centerport uses area codes 631 and 934, from NANPA's telephone records.

What time zone is 11721 in?

11721 uses America/New_York.

How many people live in 11721?

About 6,426 people live in ZIP code 11721, in 2,417 households, at 2,561.2 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 11721?

$197,179 a year, against $85,974 across New York.

What ZIP codes are near 11721?

The closest are 11768 (2.2 mi), 11740 (2.6 mi), 11743 (3 mi), 11731 (4 mi) and 11724 (5.2 mi).

Is 11721 a PO Box ZIP code?

11721 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “11721 ZIP Code — Centerport, New York (Suffolk County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/11721

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