| Event | Time | Meet | Date |
|---|---|---|---|
| 100m Backstroke | 1:42.29 | 2025 Central Region Div 2 LC Championships | 2025-06-13 |
| 100m Backstroke | 1:29.30 | 2026 Central Region Div 2 SC Championships | 2026-02-20 |
| 100m Breaststroke | 1:45.69 | Scar Pan Am Winter Classic | 2026-01-16 |
| 100m Breaststroke | 1:37.67 | 2026 Central Region Div 2 SC Championships | 2026-02-20 |
| 100m Butterfly | 1:38.84 | PICK Lisa Flood Classic 2025 | 2025-12-05 |
| 100m Freestyle | 1:16.91 | Scar Pan Am Winter Classic | 2026-01-16 |
| 100m Freestyle | 1:13.95 | Winter Swimfest 2026 | 2026-01-24 |
| 100m IM | 1:29.43 | Paul Corkum Memorial 2025 | 2025-10-18 |
| 200m Backstroke | 3:20.86 | Paul Corkum Memorial 2025 | 2025-10-18 |
| 200m Breaststroke | 3:28.59 | Winter Swimfest 2026 | 2026-01-24 |
| 200m Freestyle | 2:52.68 | 2025 Central Region Div 2 LC Championships | 2025-06-13 |
| 200m Freestyle | 2:43.36 | 2026 Central Region Div 2 SC Championships | 2026-02-20 |
| 200m IM | 3:17.36 | Scar Pan Am Winter Classic | 2026-01-16 |
| 200m IM | 3:05.97 | 2026 Central Region Div 2 SC Championships | 2026-02-20 |
| 400m Freestyle | 6:01.29 | 2025 Central Region Div 2 LC Championships | 2025-06-13 |
| 400m Freestyle | 6:09.94 | 2025 Barrie Aquafest | 2025-10-31 |
| 50m Freestyle | 33.02 | Scar Pan Am Winter Classic | 2026-01-16 |
| 50m Freestyle | 32.26 | PICK Lisa Flood Classic 2025 | 2025-12-05 |
Cheng, Millie's top personal bests include 100m Backstroke (1:42.29), 100m Backstroke (1:29.30), 100m Breaststroke (1:45.69), 100m Breaststroke (1:37.67), 100m Butterfly (1:38.84).
Cheng, Millie swims for Pickering Swim Club Inc.
Cheng, Millie has competed in 10 meets.