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zipcodes.pro — ZIP/03237

03237

ZIP 03237 is Gilmanton, New Hampshire, in Belknap County; area code 603; Eastern time.

Type
Standard
Time zone
America/New_York
County
Belknap
Metro area
Laconia, NH
Population
2,575
Coordinates
43.4316, -71.3877
☼ Live from 03237 — Gilmanton, NH

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Where 03237 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 03237
  • 🔢 Type 03237 into a pocket calculator and turn it upside down: LEZEO — not quite a word, sorry.
  • ➕ As a number, 3,237 = 3 × 13 × 83. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 110010100101
  • 🏠 Its numerical neighbours: 03235 (Franklin, NH, 14 mi away) and 03238 (Glencliff, NH, 45 mi away).
  • 🔄 Backwards, 03237 becomes 73230, which is not a ZIP code at all.
  • 👥 29 other ZIP codes are made of exactly the same digits (02337, 03273, 20373, 20733, 23307, 23703, …). The farthest-flung twin is 73023 in Chickasha, OK, 1,526 miles away.
  • 🧭 Farther north than 85% of all ZIP codes, and farther east than 95%.
  • 🎯1,420 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 03237 and you would come out at 43.43°S, 108.61°E — 886 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 25m of daylight. Shortest: 8h 57m.
  • 📏 At 38.0 square miles of land, 03237 is bigger than 52% of ZIP codes — room for about 29 Central Parks.
🌙 The sky over 03237 today
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🌋 Shake report
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Source: USGS.

People and housing

Population2,575This ZIP2,575
Households1,097This ZIP1,097
Housing units1,390This ZIP1,390
Median age43.2This ZIP43.2New Hampshire43.3US 38.9
Median household income$111,359This ZIP$111,359New Hampshire$99,031US $80,734
Median home value$345,400This ZIP$345,400New Hampshire$402,500US $332,700
Bachelor's degree or higher36.1%This ZIP36.1%
Mean commute33.0 minThis ZIP33.0 min
Population density67.8 / sq miThis ZIP67.8 / sq mi

Business and tax activity

Business establishments40This ZIP40
Employees117This ZIP117
Annual payroll$7,377,000This ZIP$7,377,000
Tax returns filed1,390This ZIP1,390
Total adjusted gross income$125,410,000This ZIP$125,410,000

Land area

Land area37.96 sq miThis ZIP37.96 sq mi
Water area1.04 sq miThis ZIP1.04 sq mi

ZIP codes near 03237

ZIPCityDistance
03837 Gilmanton Iron Works, NH 2.7 mi
03220 Belmont, NH 5.6 mi
03249 Gilford, NH 6.1 mi
03298 Tilton, NH 7.1 mi
03299 Tilton, NH 7.1 mi
03810 Alton Bay, NH 7.3 mi
03307 Loudon, NH 7.4 mi
03252 Lochmere, NH 7.9 mi
03289 Winnisquam, NH 8.0 mi
03218 Barnstead, NH 8.7 mi

Find every ZIP code within 10 miles of 03237 →

Questions about this ZIP code

Where is ZIP code 03237?

03237 is in Gilmanton, New Hampshire, in Belknap County, part of the Laconia, NH micropolitan area. Its published point location is 43.4316, -71.3877.

What county is 03237 in?

03237 lies in Belknap County.

What area code is 03237?

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

What time zone is 03237 in?

03237 uses America/New_York.

How many people live in 03237?

About 2,575 people live in ZIP code 03237, in 1,097 households, at 67.8 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 03237?

$111,359 a year, against $99,031 across New Hampshire.

What ZIP codes are near 03237?

The closest are 03837 (2.7 mi), 03220 (5.6 mi), 03249 (6.1 mi), 03298 (7.1 mi) and 03299 (7.1 mi).

Is 03237 a PO Box ZIP code?

03237 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “03237 ZIP Code — Gilmanton, New Hampshire (Belknap County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/03237

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