Dagsboro is a town in Sussex County, Delaware, United States. The population was 805 at the 2010 census. It is part of the Seaford, Delaware Micropolitan Statistical Area. Dagsboro, incorporated in the early 1900s, is a quiet town that is energized in summer by Delaware Route 26 beach traffic. The town, in the Indian River School District, was founded in 1747 and has been known as Blackfoot Town, Dagsbury and Dagsborough.