Gastonia is a city in and the county seat of Gaston County, North Carolina, United States. The most populous city in the county and the 13th-most populous city in North Carolina, the population was 80,411 at the 2020 census. It is part of the Charlotte-Concord-Gastonia, NC-SC Metropolitan Statistical Area, which is part of the Charlotte-Concord, NC-SC Combined Statistical Area.