Due to the legal settlement with CART, the Indy Racing League was unable to utilize the name IndyCar until the beginning of the 2003 season. For 1996–1997, the series was simply referred to as the Indy Racing League, with no genre designation. For 1998–1999, the series garnered its first title sponsor, and was advertised as the Pep Boys Indy Racing League. The contract was not renewed after the second year. In 2000, the series sold its naming rights to Internet search engine Northern Light for five seasons, and the series was named the Indy Racing Northern Light Series. After only two seasons, however, the sponsorship agreement ended when Northern Light reevaluated its business plan and ended all sponsorships.
The league reverted to the Indy Racing League name for the 2002 season, with no title sponsor. The IndyCar Series name was officially adopted beginning in 2003, as the series was now legally entitled to use it. In 2006, IndyCar forged an alliance with Simmons-Abramson Marketing (headed by Gene Simmons of the hard rock band Kiss), promising to be "actively engaged in the league's marketing, event, public relations, sponsorship, merchandising and branding efforts—from its IndyCar Series to the venerable Indianapolis 500". Simmons also co-authored the new IndyCar theme song, "I Am Indy". For the 2008 season, DirecTV served as a presenting sponsor, although this deal only lasted one year due to objections by the series' new cable broadcaster Versus, as it was owned by competitor Comcast.
Izod was announced as the series title sponsor beginning on November 5, 2009. Exact financial terms were not disclosed but the deal was reported to be worth at least $10 million per year for 5 years, but ran only 4 of the originally announced 5 seasons, as Izod ended its sponsorship after the 2013 season.
In 2014, Verizon Communications became title sponsor of the series through 2018. Verizon declined to renew the deal.
In January 2019, it was announced that Japanese communications company NTT would become title sponsor and official technology partner of the IndyCar Series. Its U.S. subsidiary NTT Data has been a sponsor of Chip Ganassi Racing since 2013.