At the 2012 Summer Olympics in London, Schmitt won a total of five medals: three gold, one silver, and one bronze. In her first event, the 4×100-meter freestyle relay, Schmitt won bronze with Missy Franklin, Jessica Hardy and Lia Neal, with the U.S. team finishing third behind the women's relay teams from Australia and the Netherlands. Swimming the anchor leg, Schmitt had a split of 53.54 seconds and the team finished with a total time of 3:34.24, an American record. Schmitt won the first individual Olympic medal of her career, a silver, in the 400-meter freestyle, and in doing so, set the American record for the event. Her time of 4:01.77 was just 0.32 seconds behind winner Camille Muffat. In her second and last individual event, the 200-meter freestyle, Schmitt won gold while setting a new Olympic record of 1:53.61, which was also a new American record. In the race, Schmitt won by a margin of 1.97 seconds over Muffat. In the 4×200-meter freestyle relay, Schmitt earned her second gold after passing Australian Alicia Coutts and topping the field with a split of 1:54.09 as the anchor leg. Also on the winning 4×200-meter relay team were Missy Franklin, Dana Vollmer and Shannon Vreeland. In her final event, the 4×100-meter medley relay, Schmitt won gold with Missy Franklin, Rebecca Soni, and Dana Vollmer. Swimming the freestyle leg, Schmitt recorded a time of 53.25, and the American team went on to set the world record with a time of 3:52.05, bettering the Chinese-owned record of 3:52.19 set in 2009.