Haverhill is a town and the seat of Grafton County, New Hampshire, United States. The population was 4,585 at the 2020 census. Haverhill includes the villages of Woodsville, Pike, and North Haverhill, the historic town center at Haverhill Corner, and the district of Mountain Lakes. Located here are Bedell Bridge State Park, Black Mountain State Forest, Kinder Memorial Forest, and Oliverian Valley Wildlife Preserve.