Belinda Bencic won the women's singles tennis title at the 2015 Canadian Open after Simona Halep retired in the final, with scoreline at 7–6(7–5), 6–7(4–7), 3–0. Bencic defeated six major finalists in succession en route to her first WTA Tour title. At 18 years and 23 weeks of age, Bencic became the youngest woman to win the tournament, surpassing Ana Ivanovic's record from 2006.
Agnieszka Radwańska was the defending champion, but lost in the quarterfinals to Halep.
Seeds
The top eight seeds received a bye into the second round.