South Wellfleet is part of Wellfleet, a town in Barnstable County, Massachusetts, United States located halfway between the "tip" and "elbow" of Cape Cod. The town had a population of 2,750 at the 2010 census, which swells nearly sixfold during the summer. A total of 70% of the town's land area is in protection, and nearly half of it is part of the Cape Cod National Seashore. South Wellfleet is famous for its eponymous oysters, which are celebrated in the annual October South Wellfleet OysterFest.
Guglielmo Marconi built America's first transatlantic radio transmitter station on a coastal bluff in South Wellfleet in 1901–02. The first radio telegraph transmission from America to England was sent from this station on January 18, 1903, a ceremonial telegram from President Theodore Roosevelt to King Edward VII. Most of the transmitter site is gone, however, as three quarters of the land it originally encompassed has been eroded into the sea. The South Wellfleet station's first call sign was "CC" for Cape Cod.
Wellfleet, Brewster, Eastham and Orleans make up the Nauset Regional School District. Each town operates its own elementary schools, with a regional middle school and high school accepting the students of all four towns.