Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — CITY/NH/SOMERSWORTH

Somersworth ZIP code, New Hampshire

The ZIP code for Somersworth, NH is 03878, and its area code is 603.

USPS city name
1 ZIP code
Overlapping the city
1 more
Population
12,111
Area code
603

Mail addressed to Somersworth uses the ZIP code above. 1 more ZIP code covers part of the city but is addressed as somewhere else; they are listed separately below.

Somersworth in numbers

About 12,111 people live in Somersworth, in 5,201 households, the 13th-largest of New Hampshire's 100 census places. The median household income is $74,504 a year, 25% below the New Hampshire median of $99,031 (US: $80,734). The median owner-occupied home is valued at $318,400 (21% below the New Hampshire median), and median gross rent is $1,477 a month. The median age is 38.4; 31.4% of adults 25 and over hold a bachelor's degree or higher (40.6% across New Hampshire); the average commute takes 26 minutes.

Population12,111Somersworth12,111
Households5,201Somersworth5,201
Median age38.4Somersworth38.4New Hampshire43.3US 38.9
Median household income$74,504Somersworth$74,504New Hampshire$99,031US $80,734
Median home value$318,400Somersworth$318,400New Hampshire$402,500US $332,700
Median gross rent$1,477Somersworth$1,477New Hampshire$1,491US $1,413
Bachelor's degree or higher31.4%Somersworth31.4%New Hampshire40.6%US 35.7%
Mean commute25.8 minSomersworth25.8 minNew Hampshire26.7 minUS 26.4 min
Population density1,235 / sq miSomersworth1,235 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the census place Somersworth city. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes addressed as Somersworth

ZIP codes with the USPS city name Somersworth
ZIP City Type Population Median income Median home
03878 Somersworth , NH Standard 12,205 $75,136 $317,900

Other ZIP codes overlapping Somersworth

These ZIP codes cover part of Somersworth but are addressed as somewhere else.

ZIP codes overlapping Somersworth
ZIP City Type Population Median income Median home
03820 Dover , NH Standard 33,440 $94,897 $436,100

Map of Somersworth ZIP codes

03878

The ZIP codes of Somersworth, NH, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near Somersworth

The nearest larger towns are Dover (33,364 people, 4.6 mi), Rochester (33,144 people, 5.5 mi) and Sanford, ME (22,247 people, 13 mi).

Towns near Somersworth
TownPopulationDistance
Dover 33,364 4.6 mi
South Berwick, ME 3,381 4.8 mi
Rochester 33,144 5.5 mi
Durham 10,681 7.9 mi
South Eliot, ME 4,203 9.5 mi
Newmarket 5,679 12.6 mi
Sanford, ME 22,247 13.5 mi
Kittery, ME 5,110 13.6 mi
Farmington 3,924 13.7 mi
York Harbor, ME 4,240 14.3 mi
Portsmouth 22,545 14.4 mi
Epping 2,796 18.5 mi
Exeter 9,964 19.3 mi
Kennebunk, ME 6,221 19.5 mi

More nearby: every ZIP code in Strafford County · New Hampshire ZIP codes

Cite this page

zipcodes.pro. “Somersworth, NH ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/nh/somersworth

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