The Stuttgart Open[a] (sponsored since 2022 by Hugo Boss and called the BOSS Open) is an ATP Tour 250 series professional tennis tournament on the ATP Tour.

From 1970 to 1989, the Stuttgart Open was a Grand Prix tennis circuit event.

From 1990 to 1999, the Stuttgart Open was an ATP Championship Series tournament.

Along with the move to grass courts, the tournament is now staged in the week after the French Open finishes.

[2] Under the sponsorship of Mercedes-Benz, the tournament champions were awarded a Mercedes car, in addition to the prize money.