The 2015 Verizon IndyCar Series was the 20th season of the IndyCar Series and the 104th season of American open wheel racing. Its premier event was the 99th Indianapolis 500, which was held on May 24. Will Power returned as the reigning champion, while Ryan Hunter-Reay was the defending Indy 500 champion. Chevrolet entered the season as the reigning Manufacturers' champion. Indianapolis 500 and the season finale counted for double points.
The season was overshadowed by the death of driver Justin Wilson at Pocono, after being struck on the head by debris from Sage Karam's car.
A week after Wilson's fatal accident, the finale was held at Sonoma Raceway, where Scott Dixon secured his fourth career title after a low-key season that saw him win on a tiebreak against Juan Pablo Montoya following his third win of the season after many consistent finishes leading up to the finale. Montoya won the Indianapolis 500 earlier in the season. It was a very competitive season with no standout performers and many different race winners and pacesetters. Except Dixon's three race wins, he finished on the podium only once, but due to their consistent finishing Dixon and Montoya had a significant margin to reigning champion Will Power in third.
