Stage 4 of the 2023 Tour de Suisse was a mountain stage that took place on .

The stage started in Monthey and finished in Leukerbad, starting at with an expected finish at (average speed of 39 km/h).

The total distance of the stage was 154.8 km. The stage included 0 categorized climb(s) and 0 intermediate sprint(s), and had a total elevation gain of 2597 m, and a total descent of 1647 m.