The 2015 WTA Tour was the elite professional tennis circuit organised by the Women's Tennis Association (WTA) for the 2015 tennis season. The 2015 WTA Tour calendar comprises the Grand Slam tournaments (supervised by the International Tennis Federation, the WTA Premier tournaments, the WTA International tournaments, the Fed Cup, and the year-end championships. Also included in the 2015 calendar is the Hopman Cup, which is organized by the ITF and does not distribute ranking points.
Serena Williams finished the year as world No. 1 for the fifth time in her career. She won five tournaments during the season, including three majors at the Australian Open, the French Open, and the Wimbledon Championships (completing a non-calendar year Grand Slam). She also won two Premier Mandatory and Premier 5 events.