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zipcodes.pro — ZIP/03837

03837

ZIP 03837 is Gilmanton Iron Works, New Hampshire, in Belknap County; area code 603; Eastern time.

Type
Standard
Time zone
America/New_York
County
Belknap
Metro area
Laconia, NH
Population
1,451
Coordinates
43.4223, -71.3361
☼ Live from 03837 — Gilmanton Iron Works, NH

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Where 03837 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 03837
  • 🔢 Type 03837 into a pocket calculator and turn it upside down: LEBEO — not quite a word, sorry.
  • ➕ As a number, 3,837 = 3 × 1279. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 111011111101
  • 🏠 Its numerical neighbours: 03836 (Freedom, NH, 32 mi away) and 03838 (Glen, NH, 48 mi away).
  • 🔄 Backwards, 03837 becomes 73830, which is not a ZIP code at all.
  • 👥 24 other ZIP codes are made of exactly the same digits (03873, 07833, 08733, 30378, 30738, 33708, …). The farthest-flung twin is 83703 in Boise, ID, 2,221 miles away.
  • 🧭 Farther north than 85% of all ZIP codes, and farther east than 95%.
  • 🎯1,422 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 03837 and you would come out at 43.42°S, 108.66°E — 884 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 25m of daylight. Shortest: 8h 57m.
  • 📏 At 20.0 square miles of land, 03837 is bigger than 37% of ZIP codes — room for about 15 Central Parks.
🌙 The sky over 03837 today
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Source: USGS.

People and housing

Population1,451This ZIP1,451
Households602This ZIP602
Housing units956This ZIP956
Median age55.1This ZIP55.1New Hampshire43.3US 38.9
Median household income$119,712This ZIP$119,712New Hampshire$99,031US $80,734
Median home value$409,600This ZIP$409,600New Hampshire$402,500US $332,700
Bachelor's degree or higher41.1%This ZIP41.1%
Mean commute32.8 minThis ZIP32.8 min
Population density72.7 / sq miThis ZIP72.7 / sq mi

Business and tax activity

Business establishments24This ZIP24
Employees71This ZIP71
Annual payroll$3,553,000This ZIP$3,553,000
Tax returns filed740This ZIP740
Total adjusted gross income$64,302,000This ZIP$64,302,000

Land area

Land area19.97 sq miThis ZIP19.97 sq mi
Water area0.67 sq miThis ZIP0.67 sq mi

ZIP codes near 03837

ZIPCityDistance
03237 Gilmanton, NH 2.7 mi
03225 Center Barnstead, NH 6.2 mi
03810 Alton Bay, NH 6.6 mi
03218 Barnstead, NH 6.7 mi
03249 Gilford, NH 7.0 mi
03809 Alton, NH 7.4 mi
03220 Belmont, NH 8.2 mi
03307 Loudon, NH 8.2 mi
03298 Tilton, NH 9.0 mi
03299 Tilton, NH 9.0 mi

Find every ZIP code within 10 miles of 03837 →

Questions about this ZIP code

Where is ZIP code 03837?

03837 is in Gilmanton Iron Works, New Hampshire, in Belknap County, part of the Laconia, NH micropolitan area. Its published point location is 43.4223, -71.3361.

What county is 03837 in?

03837 lies in Belknap County.

What area code is 03837?

Gilmanton Iron Works uses area code 603, from NANPA's telephone records.

What time zone is 03837 in?

03837 uses America/New_York.

How many people live in 03837?

About 1,451 people live in ZIP code 03837, in 602 households, at 72.7 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 03837?

$119,712 a year, against $99,031 across New Hampshire.

What ZIP codes are near 03837?

The closest are 03237 (2.7 mi), 03225 (6.2 mi), 03810 (6.6 mi), 03218 (6.7 mi) and 03249 (7 mi).

Is 03837 a PO Box ZIP code?

03837 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “03837 ZIP Code — Gilmanton Iron Works, New Hampshire (Belknap County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/03837

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