Kết quả phiên chạy FP3 của chặng đua GP Mexico 2021:
| Stt | Tay đua | Xe | Thời gian | Kh/cách | Lap |
| 1 | Sergio Perez | RED BULL | 1:17.024 | 15 | |
| 2 | Max Verstappen | RED BULL | 1:17.217 | +0.193s | 12 |
| 3 | Lewis Hamilton | MERCEDES | 1:17.675 | +0.651s | 14 |
| 4 | Valtteri Bottas | MERCEDES | 1:17.708 | +0.684s | 17 |
| 5 | Carlos Sainz | FERRARI | 1:18.029 | +1.005s | 20 |
| 6 | Yuki Tsunoda | ALPHATAURI | 1:18.037 | +1.013s | 25 |
| 7 | Daniel Ricciardo | MCLAREN | 1:18.121 | +1.097s | 15 |
| 8 | Pierre Gasly | ALPHATAURI | 1:18.202 | +1.178s | 18 |
| 9 | Charles Leclerc | FERRARI | 1:18.213 | +1.189s | 20 |
| 10 | Lando Norris | MCLAREN | 1:18.312 | +1.288s | 16 |
| 11 | Lance Stroll | ASTON MARTIN | 1:18.352 | +1.328s | 20 |
| 12 | Kimi Räikkönen | ALFA ROMEO | 1:18.531 | +1.507s | 22 |
| 13 | Antonio Giovinazzi | ALFA ROMEO | 1:18.556 | +1.532s | 19 |
| 14 | Sebastian Vettel | ASTON MARTIN | 1:18.614 | +1.590s | 17 |
| 15 | Fernando Alonso | ALPINE | 1:18.847 | +1.823s | 15 |
| 16 | Esteban Ocon | ALPINE | 1:18.999 | +1.975s | 17 |
| 17 | George Russell | WILLIAMS | 1:19.211 | +2.187s | 19 |
| 18 | Mick Schumacher | HAAS | 1:19.238 | +2.214s | 14 |
| 19 | Nicholas Latifi | WILLIAMS | 1:19.313 | +2.289s | 12 |
| 20 | Nikita Mazepin | HAAS | 1:20.479 | +3.455s | 15 |
Nguồn: Tổng hợp
