Colebrook is a town in Coös County, New Hampshire, United States. The population was 2,084 at the time of the 2020 census, down from 2,301 at the 2010 census. Situated in the Great North Woods Region, it is bounded on the west by the Connecticut River and home to Beaver Brook Falls Natural Area.

Coös County or Coos County is a county in the U.S. state of New Hampshire. As of the 2020 census, the population was 31,268, making it the least-populated county in the state. The county seat is Lancaster.