Gareth Lewis has 7 recorded races from GB.
| Date | Race | Distance | Time | Overall |
|---|---|---|---|---|
| 2025-04-13 | Schneider Electric Marathon de Paris 2025 — Schneider Electric Marathon de Paris | Marathon | 5:32:06 | 52112 |
| 2024-04-07 | Schneider Electric Marathon de Paris 2024 — Marathon de Paris 2024 | Marathon | 5:42:13 | 52069 |
| TCS London Marathon 2026 | Marathon | 6:18:44 | 55094 | |
| TCS London Marathon 2024 | Marathon | 5:57:05 | 48678 | |
| TCS London Marathon 2022 | Marathon | 5:02:47 | 28004 |