Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — ZIP/11791

11791

ZIP 11791 is in Syosset, New York, in Nassau County; area codes 516 and 363; Eastern time. Syosset has 2 ZIP codes; the other is 11773.

Type
Standard
Time zone
America/New_York
County
Nassau
Population
25,520
Coordinates
40.8278, -73.5028
☼ Live from 11791 — Syosset, NY

Weather right now

Asking the National Weather Service…

NEXRAD radar
Finding the nearest radar…
Local time: —

Where 11791 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 11791
  • 🔢 Type 11791 into a pocket calculator and turn it upside down: IGLII — not quite a word, sorry.
  • ➕ As a number, 11,791 = 13 × 907. Its digits add up to 19, a total 2,454 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10111000001111
  • 🏠 Its numerical neighbours: 11790 (Stony Brook, NY, 20 mi away) and 11792 (Wading River, NY, 36 mi away).
  • 🔄 Backwards, 11791 becomes 19711 — and that is a real ZIP code: Newark, DE, 141 miles away.
  • 👥 9 other ZIP codes are made of exactly the same digits (11719, 11971, 19171, 19711, 71119, 79111, …). The farthest-flung twin is 97111 in Carlton, OR, 2,488 miles away.
  • 🧭 Farther north than 65% of all ZIP codes, and farther east than 92%.
  • 🎯1,318 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 11791 and you would come out at 40.83°S, 106.50°E — 804 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 06m of daylight. Shortest: 9h 14m.
  • 📏 At 12.5 square miles of land, 11791 is bigger than 30% of ZIP codes — room for about 9.5 Central Parks.
🌙 The sky over 11791 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population25,520This ZIP25,520
Households8,113This ZIP8,113
Housing units8,322This ZIP8,322
Median age43.2This ZIP43.2New York39.8US 38.9
Median household income$202,962This ZIP$202,962New York$85,974US $80,734
Median home value$937,700This ZIP$937,700New York$423,800US $332,700
Median gross rent$3,019This ZIP$3,019New York$1,621US $1,413
Bachelor's degree or higher70.4%This ZIP70.4%
Mean commute39.8 minThis ZIP39.8 min
Population density2,039.5 / sq miThis ZIP2,039.5 / sq mi

Business and tax activity

Business establishments1,283This ZIP1,283
Employees16,204This ZIP16,204
Annual payroll$1,155,436,000This ZIP$1,155,436,000
Tax returns filed12,450This ZIP12,450
Total adjusted gross income$3,429,227,000This ZIP$3,429,227,000

Land area

Land area12.51 sq miThis ZIP12.51 sq mi
Water area0.28 sq miThis ZIP0.28 sq mi

Other place names in 11791

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

ZIP codes near 11791

ZIPCityDistance
11773 Syosset, NY 0.1 mi
11797 Woodbury, NY 1.7 mi
11732 East Norwich, NY 2.2 mi
11853 Jericho, NY 3.1 mi
11753 Jericho, NY 3.3 mi
11771 Oyster Bay, NY 3.4 mi
11724 Cold Spring Harbor, NY 3.5 mi
11803 Plainview, NY 3.5 mi
11802 Hicksville, NY 4.3 mi
11819 Hicksville, NY 4.3 mi

Find every ZIP code within 10 miles of 11791 →

Questions about this ZIP code

Where is ZIP code 11791?

11791 is in Syosset, New York, in Nassau County, part of the New York-Newark-Jersey City, NY-NJ metropolitan area. Its published point location is 40.8278, -73.5028.

What county is 11791 in?

11791 lies in Nassau County.

What area code is 11791?

Syosset uses area codes 516 and 363, from NANPA's telephone records.

What time zone is 11791 in?

11791 uses America/New_York.

How many people live in 11791?

About 25,520 people live in ZIP code 11791, in 8,113 households, at 2,039.5 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 11791?

$202,962 a year, against $85,974 across New York.

What ZIP codes are near 11791?

The closest are 11773 (0.1 mi), 11797 (1.7 mi), 11732 (2.2 mi), 11853 (3.1 mi) and 11753 (3.3 mi).

Is 11791 a PO Box ZIP code?

11791 is a standard ZIP code. A normal ZIP code with street delivery.

Download or cite

Cite this page

zipcodes.pro. “11791 ZIP Code — Syosset, New York (Nassau County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/11791

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/11791.json

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