William Mason has 5 recorded races from Chicago, Illinois, US.
| Date | Race | Distance | Time | Overall |
|---|---|---|---|---|
| 2025-08-23 | 2025 Chicago Triathlon Olympic | Ultra Marathon | 2:47:07 | 501 |
| 2024-08-24 | 2024 Chicago Triathlon International | Ultra Marathon | 2:51:46 | 589 |
| 2023-08-27 | 2023 Chicago Triathlon International | Ultra Marathon | 2:13:27 | 434 |
| 2022-08-28 | 2022 Chicago Triathlon Sprint - Individual | 1:37:39 | 154 | |
| TCS London Marathon 2025 | Marathon | 3:51:25 | 14813 |