Stage 21 of the 2023 La Vuelta Ciclista a España was a lumpy stage that took place on .

The stage started in Hipódromo de la Zarzuela and finished in Madrid. Paisaje de la Luz, starting at with an expected finish at (average speed of 38 km/h).

The total distance of the stage was 100.9 km. The stage included 0 categorized climb(s) and 1 intermediate sprint(s), and had a total elevation gain of 763 m, and a total descent of -730 m.