In 2012, Muñoz moved to the United States to compete in the Indy Lights series for Andretti Autosport. He captured two victories, including one on the oval at Auto Club Speedway and a win from the pole in Edmonton, in addition to three other podium finishes on his way to fifth in the championship. Muñoz returned to the series for the 2013 season with Andretti Autosport and announced a deal to compete in the 2013 Indianapolis 500 with the team.