Selsey Bill is a headland into the English Channel on the south coast of England in the county of West Sussex.

Selsey is a seaside town and civil parish, about eight miles (12 km) south of Chichester in West Sussex, England. Selsey lies at the southernmost point of the Manhood Peninsula, almost cut off from mainland Sussex by the sea. It is bounded to the west by Bracklesham Bay, to the north by Broad Rife, to the east by Pagham Harbour and terminates in the south at Selsey Bill. There are significant rock formations beneath the sea off both of its coasts, named the Owers rocks and Mixon rocks. Coastal erosion has been an ever-present problem for Selsey.