|Can Rossi beat Dixon for the title in 2019?|
Below is the unofficial IndyCar entry list for 2019 showing confirmed drivers and cars only.
- On September 19, 2018, it was announced that George Michael Steinbrenner IV's Steinbrenner Racing would join forces with Harding Racing to form a new two-car team under the name Harding Steinbrenner Racing.
- Meyer Shank Racing will compete in at least six races and expects to add four additional races for a total of ten in the 2019 season with driver Jack Harvey.
- On October 17, 2018, it was announced that Ed Carpenter Racing and Scuderia Corsa would team up to field Ed Jones in all road and street course events and the Indianapolis 500.
- On November 10, 2018 it was announced that McLaren Racing would return to the IndyCar Series at the 2019 Indianapolis 500 with Fernando Alonso behind the wheel. On November 26, 2018, it was revealed that McLaren's entry would be powered by Chevrolet.
- On December 6, 2018 it was also announced that Harding Steinbrenner Racing will switch to Honda engines from 2019 season beyond after spending two seasons with Chevrolet engines.
- On December 17, 2018, it was announced that DragonSpeed would make their IndyCar debut in 2019, in a 5-race program including the 2019 Indianapolis 500. The entry will be powered by Chevrolet and piloted by Ben Hanley, who will make his IndyCar debut along with the team.
- After both running the final race of the 2018 season at Sonoma with Harding Racing, 2018 Indy Lights champion Patricio O'Ward and runner-up Colton Herta will run the full season with the new partnership of Harding Steinbrenner Racing.
- On September 28, 2018, Chip Ganassi Racing announced that they had signed Felix Rosenqvist to drive for the team during the 2019 season. He will replace Ed Jones in the No. 10 car.
- On October 17, 2018, Ed Carpenter Racing announced Ed Jones would replace Jordan King driving the No. 20 car on road courses and street circuits. Jones will also drive the No. 64 car in the Indianapolis 500 as Ed Carpenter will continue driving the No. 20 car on ovals.
- On October 30, 2018, Schmidt Peterson Motorsports announced that Formula One driver Marcus Ericsson would join the team for the 2019 season to replace the seriously injured Robert Wickens, though Ericsson will be racing the No. 7 car instead of Wickens' No. 6, which remains open "when he wants and is able to return".
- On November 14, 2018, Rahal Letterman Lanigan Racing announced that Jordan King would join the team for the Indianapolis 500.
|4||Matheus Leist||Brazil||A. J. Foyt Enterprises||Chevrolet||All|
|14||Tony Kanaan||Brazil||A. J. Foyt Enterprises||Chevrolet||All|
|26||Zach Veach||USA||Andretti Autosport||Honda||All|
|27||Alexander Rossi||USA||Andretti Autosport||Honda||All|
|28||Ryan Hunter-Reay||USA||Andretti Autosport||Honda||All|
|98||Marco Andretti||USA||Andretti Herta Autosport*||Honda||All|
|9||Scott Dixon||NZ||Chip Ganassi Racing||Honda||All|
|10||Felix Rosenqvist(R)||Sweden||Chip Ganassi Racing||Honda||All|
|19||Santino Ferrucci(R)||USA||Dale Coyne Racing||Honda||All|
|18||Sebastien Bourdais||France||Dale Coyne Racing**||Honda||All|
|TBA||Ben Hanley(R)||England||DragonSpeed||Chevrolet||St P, LB, Indy, RA, M-O|
|21||Spencer Pigot||USA||Ed Carpenter Racing||Chevrolet||All|
|20||Ed Carpenter||USA||Ed Carpenter Racing||Chevrolet||Ovals Only|
|20||Ed Jones||Dubai||Ed Carpenter/Scuderia Corsa||Chevrolet||Non-Ovals|
|64||Ed Jones||Dubai||Ed Carpenter/Scuderia Corsa||Chevrolet||Indy 500|
|8||Patricio O'Ward(R)||Mexico||Harding Steinbrenner||Honda||All|
|88||Colton Herta(R)||USA||Harding Steinbrenner||Honda||All|
|TBA||Fernando Alonso||Spain||McLaren Racing||Chevrolet||Indy 500|
|60||Jack Harvey||England||Meyer Shank Racing***||Honda||TBA|
|15||Graham Rahal||USA||Rahal Letterman Lanigan Racing||Honda||All|
|30||Takuma Sato||Japan||Rahal Letterman Lanigan Racing||Honda||All|
|TBA||Jordan King||England||Rahal Letterman Lanigan Racing||Honda||Indy 500|
|5||James Hinchcliffe||Canada||Schmidt Peterson Motorsports||Honda||All|
|7||Marcus Ericsson(R)||Sweden||Schmidt Peterson Motorsports||Honda||All|
|2||Josef Newgarden||USA||Team Penske||Chevrolet||All|
|3||Helio Castroneves||Brazil||Team Penske||Chevrolet||Indy 500|
|12||Will Power||Australia||Team Penske||Chevrolet||All|
|22||Simon Pagenaud||France||Team Penske||Chevrolet||All|
*w/ Marco Andretti & Curb-Agajanian
**with Vasser Sullivan
***with Schmidt Peterson