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zipcodes.pro — ZIP/11787

11787

ZIP 11787 is Smithtown, New York, in Suffolk County; area codes 631 and 934; Eastern time.

Type
Standard
Time zone
America/New_York
County
Suffolk
Population
34,499
Coordinates
40.8529, -73.2113
☼ Live from 11787 — Smithtown, NY

Weather right now

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Local time: —

Where 11787 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 11787
  • 🔢 Type 11787 into a pocket calculator and turn it upside down: LBLII — not quite a word, sorry.
  • ➕ As a number, 11,787 = 3 × 3929. Its digits add up to 24, a total 2,425 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10111000001011
  • 🏠 Its numerical neighbours: 11786 (Shoreham, NY, 18 mi away) and 11788 (Hauppauge, NY, 2 mi away).
  • 🔄 Backwards, 11787 becomes 78711 — and that is a real ZIP code: Austin, TX, 1,552 miles away.
  • 👥 5 other ZIP codes are made of exactly the same digits (11778, 78117, 78711, 87117, 87711). The farthest-flung twin is 87117 in Kirtland Afb, NM, 1,848 miles away.
  • 🧭 Farther north than 65% of all ZIP codes, and farther east than 93%.
  • 🎯1,333 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 11787 and you would come out at 40.85°S, 106.79°E — 794 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 07m of daylight. Shortest: 9h 14m.
  • 📏 At 14.9 square miles of land, 11787 is bigger than 33% of ZIP codes — room for about 11 Central Parks.
🌙 The sky over 11787 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population34,499This ZIP34,499
Households11,857This ZIP11,857
Housing units12,136This ZIP12,136
Median age46.3This ZIP46.3New York39.8US 38.9
Median household income$143,101This ZIP$143,101New York$85,974US $80,734
Median home value$679,800This ZIP$679,800New York$423,800US $332,700
Median gross rent$2,330This ZIP$2,330New York$1,621US $1,413
Bachelor's degree or higher52.9%This ZIP52.9%
Mean commute32.4 minThis ZIP32.4 min
Population density2,315.5 / sq miThis ZIP2,315.5 / sq mi

Business and tax activity

Business establishments1,454This ZIP1,454
Employees18,002This ZIP18,002
Annual payroll$925,997,000This ZIP$925,997,000
Tax returns filed18,060This ZIP18,060
Total adjusted gross income$2,504,306,000This ZIP$2,504,306,000

Land area

Land area14.90 sq miThis ZIP14.90 sq mi
Water area0.67 sq miThis ZIP0.67 sq mi

Other place names in 11787

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

ZIP codes near 11787

ZIPCityDistance
11788 Hauppauge, NY 2.4 mi
11754 Kings Park, NY 3.0 mi
11767 Nesconset, NY 3.4 mi
11725 Commack, NY 3.7 mi
11749 Islandia, NY 3.8 mi
11780 Saint James, NY 4.5 mi
11722 Central Islip, NY 4.9 mi
11755 Lake Grove, NY 4.9 mi
11717 Brentwood, NY 5.2 mi
11731 East Northport, NY 5.6 mi

Find every ZIP code within 10 miles of 11787 →

Questions about this ZIP code

Where is ZIP code 11787?

11787 is in Smithtown, New York, in Suffolk County, part of the New York-Newark-Jersey City, NY-NJ metropolitan area. Its published point location is 40.8529, -73.2113.

What county is 11787 in?

11787 lies in Suffolk County.

What area code is 11787?

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

What time zone is 11787 in?

11787 uses America/New_York.

How many people live in 11787?

About 34,499 people live in ZIP code 11787, in 11,857 households, at 2,315.5 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 11787?

$143,101 a year, against $85,974 across New York.

What ZIP codes are near 11787?

The closest are 11788 (2.4 mi), 11754 (3 mi), 11767 (3.4 mi), 11725 (3.7 mi) and 11749 (3.8 mi).

Is 11787 a PO Box ZIP code?

11787 is a standard ZIP code. A normal ZIP code with street delivery.

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zipcodes.pro. “11787 ZIP Code — Smithtown, New York (Suffolk County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/11787

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