Antrim is a town in Hillsborough County, New Hampshire, United States. The population was 2,651 at the 2020 census. The main village in the town, where 1,395 people lived at the 2020 census, is defined as the Antrim census-designated place and is located at the intersection of U.S. Route 202 and New Hampshire Route 31. The town of Antrim also in…Antrim is a town in Hillsborough County, New Hampshire, United States. The population was 2,651 at the 2020 census. The main village in the town, where 1,395 people lived at the 2020 census, is defined as the Antrim census-designated place and is located at the intersection of U.S. Route 202 and New Hampshire Route 31. The town of Antrim also includes the villages of Antrim Center, North Branch, and Clinton Village.