Harbeson is an unincorporated community in east central Sussex County, Delaware, United States. It lies at the intersection of U.S. Route 9 and Delaware Route 5, east of the town of Georgetown, the county seat of Sussex County. Its elevation is 36 feet (11 m), and it is located at 38°43′29″N 75°17′6″W / 38.72472°N 75.285°W / 38.72472; -75.285 (38.7248347, -75.2849123). Although it is unincorporated, it has a post office, with the ZIP code of 19951. Harbeson is part of the Seaford, Delaware Micropolitan Statistical Area.