2015 Swiss Indoors – Singles

Defending champion Roger Federer defeated Rafael Nadal in the final, 6–3, 5–7, 6–3 to win the singles tennis title at the 2015 Swiss Indoors. This was Federer's tenth consecutive final at the event.

Seeds
• # Roger Federer (champion)

• # Stan Wawrinka (first round)

• #🇪🇸 Rafael Nadal (final)

• # Kevin Anderson (second round)

• #🇫🇷 Richard Gasquet (semifinals)

• #🇺🇸 John Isner (second round)

• # Marin Čilić (quarterfinals)

• #🇧🇪 David Goffin (quarterfinals)

Seeds
• # 🇫🇷 Adrian Mannarino (qualified)

• # 🇪🇸 Albert Ramos Viñolas (first round)

• # Robin Haase (qualified)

• # 🇵🇱 Jerzy Janowicz (qualified)

• # 🇺🇸 Denis Kudla (qualifying competition, lucky loser)

• # Nikoloz Basilashvili (first round)

• # 🇩🇪 Benjamin Becker (qualifying competition)

• # 🇷🇸 Dušan Lajović (qualified)

Qualifiers
• # 🇫🇷 Adrian Mannarino

• # 🇷🇸 Dušan Lajović

• # Robin Haase

• # 🇵🇱 Jerzy Janowicz

Lucky losers

 * 1) 🇺🇸 Denis Kudla