EVENT 301 Female 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 1 | Jasmine CRAM | 13 | Borocuda T | 8:45.00 |
| 4 | 3 | Matilda PENNELLS | 10 | Co Leeds | 7:12.39 |
| 5 | 2 | Charlize SCHNEIDER | 11 | Co Leeds | 7:15.64 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 5 | Lola MALCOLM | 9 | Co Leeds | 7:07.62 |
| 1 | 7 | Onadi GUNARATHNE | 10 | Co Leeds | 7:01.70 |
| 2 | 9 | Imogen BURFORD | 11 | Chester Le S | 7:00.00 |
| 3 | 11 | Matilda DARK | 10 | Co Leeds | 6:54.05 |
| 4 | 13 | Matilda SHERLEY-PRICE | 10 | Co Leeds | 6:32.70 |
| 5 | 12 | Jessica SUTCLIFFE | 10 | Co Leeds | 6:36.40 |
| 6 | 10 | Daisy RASOOL | 10 | Co Leeds | 6:57.30 |
| 7 | 8 | Eleanor HAGGARTY | 11 | Chester Le S | 7:00.00 |
| 8 | 6 | Stella BOWES | 9 | Co Leeds | 7:05.32 |
| 9 | 4 | Arina MIHAILOVA | 10 | Co Leeds | 7:09.43 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 15 | Nieve STEVENSON | 16 | Chester Le S | 6:30.00 |
| 1 | 17 | Anneliese CIRSTEA | 11 | Co Leeds | 6:27.20 |
| 2 | 19 | Mia LEIGHTON | 12 | Rotherham Mo | 6:15.50 |
| 3 | 22 | Martha NEWMAN | 10 | Co Leeds | 6:13.12 |
| 4 | 24 | Ella HARRISON | 12 | Co Leeds | 6:11.96 |
| 5 | 23 | Scarlett MAYNE | 12 | Workington | 6:12.70 |
| 6 | 20 | Amelia CARA | 13 | Camden Swiss | 6:15.10 |
| 7 | 18 | Madeleine FLAHERTY | 12 | Co Leeds | 6:19.60 |
| 8 | 16 | Elizabeth ROTHWELL | 11 | Co Leeds | 6:29.30 |
| 9 | 14 | Jinglan HUANG | 11 | Camden Swiss | 6:30.20 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 26 | Yan CHEUNG | 12 | Co Leeds | 6:09.45 |
| 1 | 28 | Evie MORAN | 12 | Co Leeds | 6:03.30 |
| 2 | 30 | Erin SHUTTLEWORTH | 13 | Workington | 5:58.40 |
| 3 | 32 | Alana RANKIN | 12 | Co Leeds | 5:52.97 |
| 4 | 34 | Tegan BISHOP | 15 | Chester Le S | 5:47.70 |
| 5 | 33 | Daria MEDVEDEVA | 13 | Camden Swiss | 5:51.20 |
| 6 | 31 | Bailey GRAHAM | 13 | Settle Srays | 5:58.10 |
| 7 | 29 | Evie THORPE | 13 | Co Leeds | 5:58.45 |
| 8 | 27 | Keira ENIKEEVA | 11 | Camden Swiss | 6:09.30 |
| 9 | 25 | Nok Ching CHAN | 13 | Camden Swiss | 6:11.20 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 36 | Saskia CLEIN | 13 | Camden Swiss | 5:45.40 |
| 1 | 38 | Jaclyn LIAW | 14 | Camden Swiss | 5:38.40 |
| 2 | 40 | Madeline BECKRAM | 12 | Co Leeds | 5:36.00 |
| 3 | 42 | Keira OSORIO | 17 | Camden Swiss | 5:33.70 |
| 4 | 44 | Lily DAVIDSON | 18 | Chester Le S | 5:32.20 |
| 5 | 43 | Anya BABOVIC | 13 | Chester Le S | 5:33.40 |
| 6 | 41 | Jessica COLLEY | 12 | Co Leeds | 5:35.70 |
| 7 | 39 | Joanna SUTTON | 14 | Copeland | 5:37.70 |
| 8 | 37 | Evelyn ATKINSON | 12 | Co Leeds | 5:45.00 |
| 9 | 35 | Valerie SHMANEVA | 12 | Camden Swiss | 5:47.00 |