The 2021 European Le Mans Series was the eighteenth season of the Automobile Club de l'Ouest's (ACO) European Le Mans Series. The six-event season began at Circuit de Barcelona-Catalunya on 18th April and finished at Algarve International Circuit on 24th October. The series was open to Le Mans Prototypes, divided into the LMP2 and LMP3 classes, and grand tourer-style racing cars in the LMGTE class.