Clayton is a town in Johnston County, North Carolina, United States, and is considered a satellite town of Raleigh. As of 2020, Clayton's population was 26,307, up from 16,116 at the 2010 census. By 2024 the town's estimated population was 30,621. Much of that growth can be attributed to the town's proximity to the Research Triangle area and access to maj…Clayton is a town in Johnston County, North Carolina, United States, and is considered a satellite town of Raleigh. As of 2020, Clayton's population was 26,307, up from 16,116 at the 2010 census. By 2024 the town's estimated population was 30,621. Much of that growth can be attributed to the town's proximity to the Research Triangle area and access to major highways such as I-40 and US 70.