Slaughter Beach is a town in Sussex County, Delaware, United States. The population was 207 at the 2010 census, an increase of 4.5% over the past decade. It is part of the Salisbury, Maryland-Delaware Metropolitan Statistical Area. Slaughter Beach was founded in 1681 and incorporated in 1931. There are at least three stories of where the town's name came from: The first is that it was named after William Slaughter, a local postmaster in the mid-19th century. The second story claims “the name came from the horseshoe crabs that wash up on shore and die each year.