Trippier signed for La Liga club Atlético Madrid on 17 July 2019 on a three-year contract, for a fee of £20 million plus add-ons. He became Atlético's first English player in 95 years. In his debut on 18 August in their opening La Liga match against Getafe, he helped the team to a 1–0 home win by providing an assist for Álvaro Morata's goal. In December 2020, Trippier was given a 10-week worldwide football ban and fined £70,000 for four breaches of Football Association betting rules after he allegedly passed on information on his transfer to his friends who then placed bets on his transfer. The ban was suspended by FIFA, which dismissed its appeal, until the case is decided by the Court of Arbitration for Sport (CAS). CAS rejected the appeal, and Trippier sat out his ban until his return to the team for the Madrid Derby against Real Madrid on 7 March 2021, which ended in a 1–1 draw.