Sampras made it official at a new conference before the evening session of the U.S. Open.
"I am 100 percent retired," Sampras said. "I knew once Wimbledon came and went it was time for me to stop."
Sampras, whose 14 Grand Slam crowns are two more than any other player, has not played competitively since he defeated longtime rival Andre Agassi in four sets to win last year's U.S. Open. Sampras, 32, won his first Grand Slam title at the U.S. Open in 1990.
He won Wimbledon seven times, the U.S. Open five times and the Australian Open twice. The top-ranked player most of the 1990s, Sampras won 64 singles title.
The 6-1 Sampras turned 32 Aug. 12.