Grantham is a town in Sullivan County, New Hampshire, United States.

The families of Howe, Dunbar and Leavitt were all early Grantham settlers.

"The Leavitts are said to have had at one time fifty children in attendance at the town's school, and over the years no fewer than seventeen teachers.

[5] Other water bodies in the town include Anderson and Butternut Ponds.

Interstate 89 crosses the town, leading northwest to Lebanon and southeast to Concord.

Route 10 leads south to Newport, the county seat, and north with I-89 to Lebanon.