| Event | Time | Meet | Date |
|---|---|---|---|
| 100m Backstroke | 1:47.00 | GO Polar Bear Invitational 2026 | 2026-01-16 |
| 100m Breaststroke | 1:51.22 | Perth Candy Cane Meet | 2025-12-12 |
| 100m Freestyle | 1:31.92 | GO Polar Bear Invitational 2026 | 2026-01-16 |
| 100m IM | 1:42.19 | GO Polar Bear Invitational 2026 | 2026-01-16 |
| 200m Backstroke | 3:47.69 | KBM Heats & Finals | 2026-02-20 |
| 200m Breaststroke | 3:59.76 | ROCS Red-Black Duel | 2025-11-22 |
| 200m Freestyle | 3:30.62 | GO Polar Bear Invitational 2026 | 2026-01-16 |
| 200m IM | 3:39.00 | GO Polar Bear Invitational 2026 | 2026-01-16 |
| 400m Freestyle | 7:07.14 | KBM Heats & Finals | 2026-02-20 |
| 50m Backstroke | 52.08 | KBM Heats & Finals | 2026-02-20 |
| 50m Breaststroke | 50.12 | KBM Heats & Finals | 2026-02-20 |
| 50m Butterfly | 45.68 | KBM Heats & Finals | 2026-02-20 |
| 50m Freestyle | 40.35 | KBM Heats & Finals | 2026-02-20 |
Millar, Mathilda's top personal bests include 100m Backstroke (1:47.00), 100m Breaststroke (1:51.22), 100m Freestyle (1:31.92), 100m IM (1:42.19), 200m Backstroke (3:47.69).
Millar, Mathilda swims for ROC Swimming.
Millar, Mathilda has competed in 6 meets.