2023 BOSS Open

The 2023 BOSS Open was a men's tennis tournament played on outdoor grass courts. It was the 45th edition of the Stuttgart Open, and part of the ATP Tour 250 series of the 2023 ATP Tour. It was held at the Tennis Club Weissenhof in Stuttgart, Germany, from 12 June until 18 June 2023.

Singles

 * 🇺🇸 Frances Tiafoe def. 🇩🇪 Jan-Lennard Struff, 4–6, 7–6(7–1), 7–6(10–8)

Doubles

 * Nikola Mektić / Mate Pavić def. 🇩🇪 Kevin Krawietz / 🇩🇪 Tim Pütz, 7–6(7–2), 6–3

Seeds

 * Rankings are as of 29 May 2023.

Other entrants
The following players received wildcards into the main draw:
 * 🇪🇸 Feliciano López
 * 🇩🇪 Oscar Otte
 * Stefanos Tsitsipas

The following players received entry from the qualifying draw:
 * 🇺🇸 Christopher Eubanks
 * 🇭🇺 Márton Fucsovics
 * Borna Gojo
 * 🇯🇵 Yosuke Watanuki

Withdrawals

 * 🇪🇸 Alejandro Davidovich Fokina → replaced by 🇫🇷 Corentin Moutet
 * 🇬🇧 Jack Draper → replaced by 🇦🇺 Christopher O'Connell
 * 🇧🇬 Grigor Dimitrov → replaced by 🇩🇪 Daniel Altmaier
 * Nicolás Jarry → replaced by 🇨🇳 Zhang Zhizhen

Seeds

 * 1 Rankings are as of 29 May 2023.

Other entrants
The following pairs received wildcards into the doubles main draw:
 * 🇩🇪 Daniel Altmaier / 🇯🇲 Dustin Brown
 * 🇩🇪 Oscar Otte / 🇩🇪 Jan-Lennard Struff

Withdrawals

 * 🇨🇴 Nicolás Barrientos / Nicolás Jarry → replaced by  Romain Arneodo / 🇫🇷 Grégoire Barrère
 * 🇬🇧 Julian Cash / 🇬🇧 Henry Patten → replaced by Aslan Karatsev / 🇨🇿 Jiří Lehečka
 * Ivan Dodig / 🇺🇸 Austin Krajicek → replaced by 🇺🇸 William Blumberg / 🇺🇸 Frances Tiafoe
 * 🇺🇸 Rajeev Ram / 🇬🇧 Joe Salisbury → replaced by 🇫🇷 Albano Olivetti / 🇪🇸 David Vega Hernández