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zipcodes.pro — ZIP/03857

03857

ZIP 03857 is Newmarket, New Hampshire, in Rockingham County; area code 603; Eastern time.

Type
Standard
Time zone
America/New_York
County
Rockingham
Population
9,463
Coordinates
43.0709, -70.9469
☼ Live from 03857 — Newmarket, NH

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Where 03857 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 03857
  • 🔢 Type 03857 into a pocket calculator and turn it upside down: LSBEO — not quite a word, sorry.
  • ➕ As a number, 3,857 = 7 × 19 × 29. Its digits add up to 23, a total 2,533 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 111100010001
  • 🏠 Its numerical neighbours: 03856 (Newfields, NH, 2 mi away) and 03858 (Newton, NH, 15 mi away).
  • 🔄 Backwards, 03857 becomes 75830, which is not a ZIP code at all.
  • 👥 51 other ZIP codes are made of exactly the same digits (03785, 03875, 05738, 05837, 05873, 07538, …). The farthest-flung twin is 85307 in Glendale, AZ, 2,312 miles away.
  • 🧭 Farther north than 83% of all ZIP codes, and farther east than 96%.
  • 🎯1,442 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 03857 and you would come out at 43.07°S, 109.05°E — 853 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 22m of daylight. Shortest: 9h 00m.
  • 📏 At 12.6 square miles of land, 03857 is bigger than 30% of ZIP codes — room for about 9.6 Central Parks.
🌙 The sky over 03857 today
  • Working out the sun…
🌋 Shake report
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Source: USGS.

People and housing

Population9,463This ZIP9,463
Households4,345This ZIP4,345
Housing units4,500This ZIP4,500
Median age41.2This ZIP41.2New Hampshire43.3US 38.9
Median household income$100,845This ZIP$100,845New Hampshire$99,031US $80,734
Median home value$455,000This ZIP$455,000New Hampshire$402,500US $332,700
Median gross rent$1,671This ZIP$1,671New Hampshire$1,491US $1,413
Bachelor's degree or higher49.7%This ZIP49.7%
Mean commute28.2 minThis ZIP28.2 min
Population density751.4 / sq miThis ZIP751.4 / sq mi

Business and tax activity

Business establishments152This ZIP152
Employees1,412This ZIP1,412
Annual payroll$73,186,000This ZIP$73,186,000
Tax returns filed5,230This ZIP5,230
Total adjusted gross income$497,996,000This ZIP$497,996,000

Land area

Land area12.59 sq miThis ZIP12.59 sq mi
Water area1.60 sq miThis ZIP1.60 sq mi

Other place names in 03857

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

ZIP codes near 03857

ZIPCityDistance
03856 Newfields, NH 2.5 mi
03824 Durham, NH 3.5 mi
03885 Stratham, NH 4.5 mi
03861 Lee, NH 4.5 mi
03840 Greenland, NH 5.6 mi
03843 Hampton, NH 5.6 mi
03833 Exeter, NH 6.6 mi
03801 Portsmouth, NH 7.1 mi
03823 Madbury, NH 7.2 mi
03042 Epping, NH 7.3 mi

Find every ZIP code within 10 miles of 03857 →

Questions about this ZIP code

Where is ZIP code 03857?

03857 is in Newmarket, New Hampshire, in Rockingham County, part of the Boston-Cambridge-Newton, MA-NH metropolitan area. Its published point location is 43.0709, -70.9469.

What county is 03857 in?

03857 lies in Rockingham County.

What area code is 03857?

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

What time zone is 03857 in?

03857 uses America/New_York.

How many people live in 03857?

About 9,463 people live in ZIP code 03857, in 4,345 households, at 751.4 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 03857?

$100,845 a year, against $99,031 across New Hampshire.

What ZIP codes are near 03857?

The closest are 03856 (2.5 mi), 03824 (3.5 mi), 03885 (4.5 mi), 03861 (4.5 mi) and 03840 (5.6 mi).

Is 03857 a PO Box ZIP code?

03857 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “03857 ZIP Code — Newmarket, New Hampshire (Rockingham County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/03857

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