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 — STATE/NH/COUNTY/STRAFFORD

Strafford County, NH ZIP codes

There are 20 ZIP codes in Strafford County, NH, in 15 towns, from 03815 to 03887. The largest are 03820 (Dover), 03867 (Rochester) and 03878 (Somersworth).

The county seat is Dover.

ZIP codes
20
Towns
15
County seat
Dover
County FIPS
33017
Population
132,575
Median household income
$88,570
Land area
367 sq mi
Area code
603

Strafford County ZIP codes by town

Dover (county seat)
03820, 03821, 03822

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

Map of Strafford County ZIP codes

0381503820038210382203823038240382503835038390385103852038550386103866038670386803869038780388403887

The ZIP codes of Strafford County, 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.

Strafford County in numbers

About 132,575 people live in Strafford County, in 52,080 households, the 4th most populous of New Hampshire's 10 counties. The median household income is $88,570 a year, 11% below the New Hampshire median of $99,031 (US: $80,734). The median owner-occupied home is valued at $362,800 (10% below the New Hampshire median), and median gross rent is $1,488 a month. The median age is 38.2; 39.3% of adults 25 and over hold a bachelor's degree or higher (40.6% across New Hampshire); the average commute takes 26 minutes.

Population132,575Strafford132,575
Households52,080Strafford52,080
Median age38.2Strafford38.2New Hampshire43.3US 38.9
Median household income$88,570Strafford$88,570New Hampshire$99,031US $80,734
Median home value$362,800Strafford$362,800New Hampshire$402,500US $332,700
Median gross rent$1,488Strafford$1,488New Hampshire$1,491US $1,413
Bachelor's degree or higher39.3%Strafford39.3%New Hampshire40.6%US 35.7%
Mean commute26.0 minStrafford26.0 minNew Hampshire26.7 minUS 26.4 min
Population density361 / sq miStrafford361 / sq mi

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

Largest towns in Strafford County

Largest towns in Strafford County
TownZIP codesPopulation
Dover 3 33,364
Rochester 4 33,144
Somersworth 1 12,111
Durham 1 10,681
Barrington 1 9,489
Lee 1 4,576
Strafford 1 4,306
Farmington 1 3,924
New Durham 1 2,748
Rollinsford 1 2,456
Madbury 1 2,203
Milton 1 356
Union 1 131
Milton Mills 1 72

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Strafford County.

Not sure you are in Strafford County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Strafford County, with figures

ZIP codes in Strafford County
ZIP City Type Population Median income Median home
03815 Center Strafford , NH No street area — — —
03820 Dover , NH Standard 33,440 $94,897 $436,100
03821 Dover , NH No street area — — —
03822 Dover , NH No street area — — —
03823 Madbury , NH Standard 2,203 $148,365 $476,900
03824 Durham , NH Standard 15,080 $124,056 $504,300
03825 Barrington , NH Standard 9,489 $110,323 $399,100
03835 Farmington , NH Standard 6,804 $66,982 $289,800
03839 Rochester , NH Standard 4,279 $88,346 $335,600
03851 Milton , NH Standard 4,333 $93,412 $314,300
03852 Milton Mills , NH Standard 205 $154,583 $357,100
03855 New Durham , NH Standard 2,748 $100,194 $339,400
03861 Lee , NH Standard 4,576 $131,579 $480,600
03866 Rochester , NH No street area — — —
03867 Rochester , NH Standard 22,732 $78,674 $273,900
03868 Rochester , NH Standard 6,133 $81,530 $268,800
03869 Rollinsford , NH Standard 2,456 $87,215 $413,500
03878 Somersworth , NH Standard 12,205 $75,136 $317,900
03884 Strafford , NH Standard 4,306 $122,105 $427,900
03887 Union , NH Standard 1,739 $91,875 $292,800

Cite this page

zipcodes.pro. “Strafford County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/nh/county/strafford

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