Results: Iowa 300
| Pos | Driver | Grid | C/A/E/T | Laps | Race time, gap | Laps led | Status | Pit stops |
| 1 | Helio Castroneves | 3 | D/C/C/F | 300 | 01:55:11.2807 | 217 | Running | 5 |
| 2 | JR Hildebrand | 2 | D/C/C/F | 300 | +3.9647 | 38 | Running | 5 |
| 3 | Ryan Hunter-Reay | 15 | D/H/H/F | 300 | +4.5845 | – | Running | 5 |
| 4 | Will Power | 1 | D/C/C/F | 300 | +5.7403 | 23 | Running | 5 |
| 5 | Graham Rahal | 10 | D/H/H/F | 300 | +10.1811 | – | Running | 5 |
| 6 | Josef Newgarden | 16 | D/C/C/F | 300 | +11.0500 | 1 | Running | 6 |
| 7 | Simon Pagenaud | 11 | D/C/C/F | 300 | +12.2562 | 2 | Running | 6 |
| 8 | Scott Dixon | 17 | D/H/H/F | 300 | +14.3653 | – | Running | 6 |
| 9 | Tony Kanaan | 7 | D/H/H/F | 300 | +15.1184 | – | Running | 5 |
| 10 | James Hinchcliffe | 9 | D/H/H/F | 300 | +15.8243 | – | Running | 5 |
| 11 | Alexander Rossi | 12 | D/H/H/F | 299 | +1 lap | – | Running | 5 |
| 12 | Ed Carpenter | 4 | D/C/C/F | 299 | +1 lap | – | Running | 5 |
| 13 | Esteban Gutierrez (R) | 18 | D/H/H/F | 299 | +1 lap | – | Running | 5 |
| 14 | Max Chilton | 13 | D/H/H/F | 299 | +1 lap | 2 | Running | 5 |
| 15 | Charlie Kimball | 14 | D/H/H/F | 298 | +2 laps | 10 | Running | 5 |
| 16 | Takuma Sato | 5 | D/H/H/F | 298 | +2 laps | – | Running | 6 |
| 17 | Marco Andretti | 20 | D/H/H/F | 298 | +2 laps | 7 | Running | 6 |
| 18 | Ed Jones (R) | 8 | D/H/H/F | 297 | +3 laps | – | Running | 6 |
| 19 | Conor Daly | 19 | D/C/C/F | 168 | +132 laps | – | Contact | 4 |
| 20 | Carlos Munoz | 21 | D/C/C/F | 130 | +170 laps | – | Contact | 2 |
| 21 | Mikhail Aleshin | 6 | D/H/H/F | 56 | +244 laps | – | Contact | 0 |
(C)hassis: D=Dallara | (A)erokit: C=Chevy, H=Honda | (E)ngine: C=Chevy, H=Honda | (T)yre: F=Firestone
Note: Additional pit stop counted for most drivers due to red flag
