In June 2012, Sutton became the first American to make Olympic swimming teams in both open water and pool events. At the 2012 United States Olympic Trials, she earned a spot for the U.S. Olympic team in the 400-meter freestyle to go along with her 2008 Olympic appearance in the open water event. In the 400-meter freestyle final, Sutton placed second behind Allison Schmitt. She also competed in the 800-meter freestyle and finished fourth in the final. At the 2012 Summer Olympics in London, she finished tenth in the preliminary heats of the 400-meter freestyle, and was not among the top eight to advance to the final.