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. The main village of the town, where 1,201 people resided at the 2020 census, is defined as the Colebrook census-designated place, and is located at the junction of U.S. Route 3 with New Hampshire Route 26.