For 2021 Colton Herta moved from the #88 Andretti Harding Steinbrenner Racing car to the #26 Andretti Autosport with Curb Agajanian car with backing from Indianapolis 500 title sponsor Gainbridge. Herta won the Firestone Grand Prix of St. Petersburg, the second round of the series. Then after a couple of podiums in the mid-season he scored two more wins in the two final races of the year – at Laguna Seca and Long Beach. He ultimately finished the season fifth in the championship standings.
| Season | Series | Event |
| 2021 | IndyCar Series | |
| Driver | No. | Entrant |
| Colton Herta | 26 | Andretti Autosport w/ Curb-Agajanian |
| Chassis | Engine | Car Name |
| Dallara DW12 (IR18) | Honda | Gainbridge / Curb |
| Scale | Manufacturer | Collection |
| 1:64 | Greenlight | |
| Cat. No. | Quality | Rarity |
| 11509 | 
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