Strafford County is a county in the U.S. state of New Hampshire. As of the 2020 census, the population was 130,889. Its county seat is Dover. Strafford County was one of the five original counties identified for New Hampshire in 1769. It was named after William Wentworth, 2nd Earl of Strafford in the mistaken belief that he was the ancestor of governor John Wentworth – although they were distantly related, William had no descendants. The county was organized at Dover in 1771. In 1840, the size of the original county was reduced with the creation of Belknap County.
Strafford County constitutes a portion of the Boston-Cambridge-Newton, MA-NH Metropolitan Statistical Area as well as of the greater Boston-Worcester-Providence, MA-RI-NH-CT Combined Statistical Area. It is estimated to be New Hampshire's county with the highest percentage growth over the 2010–2019 period.
Geography
Strafford County is in southeastern New Hampshire, separated from York County in the state of Maine by the Salmon Falls River. The southern part of the Salmon Falls, from Rollinsford to Dover, is a tidal river that flows into the Piscataqua River.
According to the United States Census Bureau, the county has a total area of , of which is land and (3.9%) is water. It is the smallest county in New Hampshire by area.
Adjacent counties
- Carroll County (north)
- York County, Maine (east)
- Rockingham County (south)
- Merrimack County (west)
- Belknap County (northwest)