The 2023 Swiss Indoors was a men's tennis tournament played on indoor hard courts. It was the 52nd edition of the event, and part of the 500 series of the 2023 ATP Tour. It was held at the St. Jakobshalle in Basel, Switzerland, from 23 October until 29 October 2023. Sixth-seeded Félix Auger-Aliassime won his second consecutive singles title at the event.
Finals
Singles
Félix Auger-Aliassime def. Hubert Hurkacz, 7–6(7–3), 7–6(7–5)
Doubles
Santiago González / Édouard Roger-Vasselin def. Hugo Nys / Jan Zieliński, 6–7(8–10), 7–6(7–3), [10–1]
Singles main draw entrants
Seeds
Rankings are as of 16 October 2023
Other entrants
The following players received wildcards into the singles main draw: Félix Auger-Aliassime Dominic Stricker Leandro Riedi
The following player received entry into the singles main draw as a special exempt: Marcos Giron
The following players received entry from the qualifying draw: Benjamin Hassan Christopher O'Connell Alexander Shevchenko Botic van de Zandschulp
The following player received entry as a lucky loser: Thiago Seyboth Wild
Withdrawals
Carlos Alcaraz → replaced by Stan Wawrinka
Alejandro Davidovich Fokina → replaced by Yannick Hanfmann
Laslo Djere → replaced by Thiago Seyboth Wild
Milos Raonic → replaced by Miomir Kecmanović
Doubles main draw entrants
Seeds
1 Rankings as of 16 October 2023
Other entrants
The following pairs received wildcards into the doubles main draw: Mika Brunold / Marc-Andrea Hüsler Leandro Riedi / Dominic Stricker
The following pair received entry from the qualifying draw: Constantin Frantzen / Hendrik Jebens
The following pair received entry as lucky losers: Nikola Ćaćić / Victor Vlad Cornea
Withdrawals
Marcel Granollers / Horacio Zeballos → replaced by Nikola Ćaćić / Victor Vlad Cornea