Andretti Autosport locked in driver Ryan Hunter-Reay and sponsor DHL Express through the 2020 season.
The contract extensions were announced before Monday's season finale at Sonoma Raceway.
DHL has been with Andretti since 2011, and its renewal was revealed on the same day longtime IndyCar sponsor Target marked its final race after 27 years. Target has been the primary sponsor for Chip Ganassi and was considered one of the longest partnerships in sports.
DHL first began working with Andretti in 2005 and expanded into a full-time sponsor of the No. 28 six years later.
Hunter-Reay is the most successful active American driver in the IndyCar Series with 16 victories, 36 podiums, a win in the 2014 Indianapolis 500 and a championship in 2012.