Joint overnight leader Tyrrell Hatton shot a final-round five-under 66 but finished two shots behind RBC Heritage winner Webb Simpson in South Carolina.
Simpson carded a bogey-free 64, holing five birdies in the final seven holes, to win on a tournament record 22 under.
Abraham Ancer shot a 65 as he finished second on 21 under at Hilton Head.
Englishman Hatton, who shared the lead after round three with Simpson, Ancer and Ryan Palmer, had four birdies on his front nine as he finished 20 under. (BBC)