EVENT 401 Female 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 1 | Ayla CARRY | 11 | Co Leeds | 7:40.00 |
| 1 | 3 | Eve HEPBURN-WOOD | 11 | Co Leeds | 7:25.00 |
| 2 | 5 | Sophia WEEKS | 11 | Co Leeds | 7:10.00 |
| 3 | 7 | Emilia GRAVILLE | 10 | Co Leeds | 6:50.90 |
| 4 | 9 | Katie SADLER | 10 | Co Leeds | 6:41.60 |
| 5 | 8 | Evie MORAN | 11 | Co Leeds | 6:45.00 |
| 6 | 6 | Isabelle LOK | 10 | Co Leeds | 6:56.70 |
| 7 | 4 | Alice BEST | 11 | RichmondDale | 7:19.40 |
| 8 | 2 | Stephanie WILSON | 13 | Borocuda T | 7:28.70 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 11 | Isla CUNDILL | 11 | Co Leeds | 6:19.90 |
| 1 | 13 | Charis GREEN | 12 | Stokesley | 6:16.80 |
| 2 | 15 | Isabelle PARK | 11 | Co Leeds | 6:14.40 |
| 3 | 17 | Ava MCLARKEY | 11 | Co Leeds | 6:12.90 |
| 4 | 19 | Betsy KIRKLEY | 11 | Co Leeds | 6:09.10 |
| 5 | 18 | Evelyn ATKINSON | 11 | Co Leeds | 6:11.20 |
| 6 | 16 | Jessica COLLEY | 11 | Co Leeds | 6:13.50 |
| 7 | 14 | Harriet BINKS | 13 | Thirsk WH | 6:15.00 |
| 8 | 12 | Isabella STOICESCU | 12 | Co Leeds | 6:19.51 |
| 9 | 10 | Evie COOK | 11 | Co Leeds | 6:32.60 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 21 | Livia STACEY | 12 | Co Leeds | 6:01.00 |
| 1 | 23 | Holly BINKS | 16 | Thirsk WH | 6:00.00 |
| 2 | 25 | Yarah GHAZAL | 13 | Lancaster | 5:57.40 |
| 3 | 27 | Neve STAFFORD | 11 | Co Leeds | 5:54.10 |
| 4 | 29 | Eva SYLVESTER | 12 | Co Leeds | 5:52.40 |
| 5 | 28 | Bethany MAKWEMBERE | 12 | Preston | 5:52.80 |
| 6 | 26 | Nevaeh GORDON | 15 | RichmondDale | 5:55.29 |
| 7 | 24 | Pinklily TAREK | 13 | Warrington W | 5:59.44 |
| 8 | 22 | Zoe FEATHER | 11 | Co Leeds | 6:00.80 |
| 9 | 20 | Christabella TURNER | 16 | Eckington | 6:04.80 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 31 | Elizabeth BOND | 12 | Co Leeds | 5:49.50 |
| 1 | 33 | Evie-Rose TOPPING | 13 | Co Leeds | 5:47.20 |
| 2 | 35 | Grace O'HARA | 12 | Co Leeds | 5:41.80 |
| 3 | 37 | Jessica ROLLINGS | 12 | Co Leeds | 5:31.00 |
| 4 | 39 | Holly HARRISON | 14 | Co Leeds | 5:28.66 |
| 5 | 38 | Erin BENTLEY | 13 | Co Leeds | 5:29.80 |
| 6 | 36 | Emily SCHOFIELD | 15 | Stokesley | 5:32.90 |
| 7 | 34 | Addison CROPPER | 11 | Co Leeds | 5:43.53 |
| 8 | 32 | Willow WRIGHT | 11 | Co Leeds | 5:47.50 |
| 9 | 30 | Phoebe DILWORTH | 12 | RichmondDale | 5:51.32 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 41 | Elizabeth DIXON | 15 | Co Leeds | 5:24.20 |
| 1 | 43 | Emily ENGLAND-HALL | 12 | Co Leeds | 5:22.70 |
| 2 | 45 | Scarlett CAPALDI | 14 | Stokesley | 5:16.10 |
| 3 | 47 | Isabelle HALL | 13 | Co Leeds | 5:11.30 |
| 4 | 49 | Darcey CROSSLEY | 16 | Co Leeds | 5:04.84 |
| 5 | 48 | Isabel HANDLEY | 15 | Co Leeds | 5:10.36 |
| 6 | 46 | Mei YUASA | 14 | Co Leeds | 5:11.50 |
| 7 | 44 | Elkie FOSTER | 13 | Co Leeds | 5:20.20 |
| 8 | 42 | Mia TRAVIS-JONES | 14 | Co Leeds | 5:23.80 |
| 9 | 40 | Imogen CLARKSON | 13 | Clitheroe | 5:24.85 |