ZIP codes in Strafford County
21 ZIPs touch Strafford County, New Hampshire. The blue dashed line is the county border; orange ZIPs reach into it.
21
ZIP codes
2
cross the county line
140,158
people in these ZIPs
10
counties in NH
Most people
Strafford County ZIP list
More counties in New Hampshire
- Cheshire County29
- Coos County17
- Grafton County40
- Hillsborough County39
- Merrimack County34
- Rockingham County46
- Sullivan County21
Questions people actually ask
How many ZIP codes are in Strafford County, New Hampshire?
21 ZIP codes reach into Strafford County, including 4 PO Box or single-address ZIPs placed by the town they serve. 2 of them are only partly in the county and also cover a neighboring county.
Which ZIP code in Strafford County has the most people?
03820 (Dover) has about 33,440 residents, the most of any ZIP touching Strafford County, in the Census Bureau’s ACS 2020–2024 estimates.
Can a ZIP code be in Strafford County and another county?
Yes. ZIP codes follow mail routes, not county lines. Rows marked with a percentage show how much of that ZIP’s land is in Strafford County. For one address, pin the exact spot on the ZIP finder to see its county.
Where does this list come from?
ZIP areas and their county overlaps come from the Census Bureau’s 2020 ZIP Code Tabulation Area to county relationship file. PO Box ZIPs have no area, so each is placed in the county of the ZIP area nearest the town it serves.
Keep exploring
Updated 2026-11-10 · Where the data comes from