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zipcodes.pro — ZIP/03878

03878

ZIP 03878 is Somersworth, New Hampshire, in Strafford County; area code 603; Eastern time.

Type
Standard
Time zone
America/New_York
County
Strafford
Population
12,205
Coordinates
43.2535, -70.8879
☼ Live from 03878 — Somersworth, NH

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Where 03878 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 03878
  • 🔢 Type 03878 into a pocket calculator and turn it upside down: BLBEO — not quite a word, sorry.
  • ➕ As a number, 3,878 = 2 × 7 × 277. Its digits add up to 26, a total 2,038 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 111100100110
  • 🏠 Its numerical neighbours: 03875 (Silver Lake, NH, 47 mi away) and 03882 (Effingham, NH, 35 mi away).
  • 🔄 Backwards, 03878 becomes 87830 — and that is a real ZIP code: Reserve, NM, 2,130 miles away.
  • 👥 16 other ZIP codes are made of exactly the same digits (03887, 07838, 08738, 08837, 08873, 37088, …). The farthest-flung twin is 83708 in Boise, ID, 2,250 miles away.
  • 🧭 Farther north than 84% of all ZIP codes, and farther east than 96%.
  • 🎯1,445 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 03878 and you would come out at 43.25°S, 109.11°E — 863 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 24m of daylight. Shortest: 8h 58m.
  • 📏 At 9.8 square miles of land, 03878 is bigger than 27% of ZIP codes — room for about 7.5 Central Parks.
🌙 The sky over 03878 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population12,205This ZIP12,205
Households5,245This ZIP5,245
Housing units5,690This ZIP5,690
Median age38.5This ZIP38.5New Hampshire43.3US 38.9
Median household income$75,136This ZIP$75,136New Hampshire$99,031US $80,734
Median home value$317,900This ZIP$317,900New Hampshire$402,500US $332,700
Median gross rent$1,479This ZIP$1,479New Hampshire$1,491US $1,413
Bachelor's degree or higher31.3%This ZIP31.3%
Mean commute25.8 minThis ZIP25.8 min
Population density1,243.1 / sq miThis ZIP1,243.1 / sq mi

Business and tax activity

Business establishments318This ZIP318
Employees5,139This ZIP5,139
Annual payroll$241,871,000This ZIP$241,871,000
Tax returns filed6,670This ZIP6,670
Total adjusted gross income$458,688,000This ZIP$458,688,000

Land area

Land area9.82 sq miThis ZIP9.82 sq mi
Water area0.19 sq miThis ZIP0.19 sq mi

Other place names in 03878

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

ZIP codes near 03878

ZIPCityDistance
03869 Rollinsford, NH 3.2 mi
03821 Dover, NH 3.9 mi
03822 Dover, NH 3.9 mi
03901 Berwick, ME 3.9 mi
03820 Dover, NH 4.6 mi
03839 Rochester, NH 5.0 mi
03868 Rochester, NH 5.6 mi
03866 Rochester, NH 5.6 mi
03823 Madbury, NH 6.1 mi
03867 Rochester, NH 6.2 mi

Find every ZIP code within 10 miles of 03878 →

Questions about this ZIP code

Where is ZIP code 03878?

03878 is in Somersworth, New Hampshire, in Strafford County, part of the Boston-Cambridge-Newton, MA-NH metropolitan area. Its published point location is 43.2535, -70.8879.

What county is 03878 in?

03878 lies in Strafford County.

What area code is 03878?

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

What time zone is 03878 in?

03878 uses America/New_York.

How many people live in 03878?

About 12,205 people live in ZIP code 03878, in 5,245 households, at 1,243.1 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 03878?

$75,136 a year, against $99,031 across New Hampshire.

What ZIP codes are near 03878?

The closest are 03869 (3.2 mi), 03821 (3.9 mi), 03822 (3.9 mi), 03901 (3.9 mi) and 03820 (4.6 mi).

Is 03878 a PO Box ZIP code?

03878 is a standard ZIP code. A normal ZIP code with street delivery.

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zipcodes.pro. “03878 ZIP Code — Somersworth, New Hampshire (Strafford County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/03878

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