| Event | Time | Meet | Date |
|---|---|---|---|
| 100m Backstroke | 1:26.19 | 2026 AA & AAA Winter Champs | 2026-03-05 |
| 100m Butterfly | 1:29.19 | 2026 AA & AAA Winter Champs | 2026-03-05 |
| 100m Freestyle | 1:15.46 | 2026 AA & AAA Winter Champs | 2026-03-05 |
| 100m IM | 1:35.44 | 2025 DAL Sprint Meet | 2025-10-19 |
| 200m Backstroke | 3:00.77 | 2026 AA & AAA Winter Champs | 2026-03-05 |
| 200m Freestyle | 2:43.41 | 2026 AA & AAA Winter Champs | 2026-03-05 |
| 200m IM | 3:29.02 | AA AGD Meet & Nova Tech #3 Central | 2026-01-24 |
| 400m Freestyle | 6:13.56 | AA Age Group Development Meet & Nova Tech #4 C | 2026-02-14 |
| 50m Backstroke | 42.44 | 2025 DAL Sprint Meet | 2025-10-19 |
| 50m Breaststroke | 55.75 | 2025 DAL Sprint Meet | 2025-10-19 |
| 50m Butterfly | 41.29 | 2025 DAL Sprint Meet | 2025-10-19 |
| 50m Freestyle | 32.62 | 2026 AA & AAA Winter Champs | 2026-03-05 |
| 800m Freestyle | 12:51.19 | AA AGD Meet & Nova Tech #3 Central | 2026-01-24 |
MacDonald, William's top personal bests include 100m Backstroke (1:26.19), 100m Butterfly (1:29.19), 100m Freestyle (1:15.46), 100m IM (1:35.44), 200m Backstroke (3:00.77).
MacDonald, William swims for Dartmouth Crusaders Swim Club.
MacDonald, William has competed in 8 meets.