Altamahaw is a census-designated place in Alamance County, North Carolina, United States. It is part of the Burlington, North Carolina Metropolitan Statistical Area. As of the 2010 census it had a population of 347. The community was listed as Altamahaw-Ossipee at the 2000 census, at which time the population was 996. The town of Ossipee incorporated in 2002 and currently has a population of 543. The remainder of the territory was reassigned as the Altamahaw CDP.