William Mackean has 5 recorded races from GB.
| Date | Race | Distance | Time | Overall |
|---|---|---|---|---|
| 2024-04-07 | Schneider Electric Marathon de Paris 2024 — Marathon de Paris 2024 | Marathon | 2:56:45 | 1437 |
| 2024-04-07 | Schneider Electric Marathon de Paris 2024 — Marathon de Paris 2024 | Marathon | 3:11:34 | 3972 |
| TCS London Marathon 2026 | Marathon | 2:54:21 | 2146 |