2019 WTA Finals – Singles
Ashleigh Barty defeated the defending champion Elina Svitolina in the final, 6–4, 6–3 to win the singles tennis title at the 2019 WTA Finals. With the win, Barty became the fifth woman (after Serena Williams, Maria Sharapova, Petra Kvitová, and Dominika Cibulková) to win the tournament on her first attempt. Barty was also the third player to win both the WTA Finals and the WTA Elite Trophy after Venus Williams and Petra Kvitová. Barty won $4.42 million USD in prize money by claiming the title, the most prize money ever won by a player at  a single tennis tournament, male or female. Barty, Bianca Andreescu, Belinda Bencic and Sofia Kenin (as an alternate replacing Andreescu) made their debuts in the event. This was the first edition of the tournament since 2009 where both alternates were used. Barty secured the year-end world No. 1 singles ranking after playing her second round robin match. Karolína Plíšková and Naomi Osaka were also in contention for the top ranking at the start of the tournament. The tiebreak played between Elina Svitolina and Karolína Plíšková in round-robin stage, which Svitolina won 14–12, was the longest of the 2019  season. Draw. Red group. † Following WTA rules, Bertens' retirement against Bencic was counted as a straight-set loss in determining round robin standings. Purple group. † Following WTA rules, Andreescu's retirement against Plíšková was counted as a straight-set loss in determining round robin standings.