Stage 20 of the 2024 La Vuelta Ciclista a España was a mountain stage that took place on .

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

The total distance of the stage was 171.9 km. The stage included 0 categorized climb(s) and 0 intermediate sprint(s), and had a total elevation gain of 4574 m, and a total descent of -3671 m.