EVENT 401 Female 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 2 | Paige BAGSHAW | 14 | Nova Cent'n | 4:56.60 |
| 2 | 4 | Willow WRIGHT | 12 | Co Leeds | 4:55.57 |
| 3 | 6 | Isobel KEENS | 14 | Rotherham Mo | 4:54.40 |
| 4 | 8 | Effie CHAPMAN | 13 | Nova Cent'n | 4:53.61 |
| 5 | 7 | Elyse HAZELDEN | 14 | Cleethorpes | 4:53.90 |
| 6 | 5 | Olivia BYRNE | 13 | Bo Barnsley | 4:55.40 |
| 7 | 3 | Freya COOPER | 14 | Donc Dartes | 4:55.63 |
| 8 | 1 | Megan BARNICOAT | 14 | Co Peterboro | 4:56.92 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 10 | Ava HANDS | 14 | Nuneaton | 4:51.40 |
| 1 | 12 | Amaja WATERS | 14 | Harrogate | 4:48.30 |
| 2 | 14 | Mia ROBINSON | 14 | Southport | 4:47.05 |
| 3 | 16 | Lily CATTLIN | 15 | Rotherham Mo | 4:43.23 |
| 4 | 18 | Emily TABERN | 15 | Warrington W | 4:42.60 |
| 5 | 17 | Esme SLEDGE | 16 | Co Birm'ham | 4:42.62 |
| 6 | 15 | Esme BEEVERS | 14 | Rotherham Mo | 4:43.40 |
| 7 | 13 | Emilia SPENCE | 14 | Co Birm'ham | 4:47.10 |
| 8 | 11 | Daisy D'ARCY | 14 | Co Liverpool | 4:48.90 |
| 9 | 9 | Lucy WILLATTS | 14 | Grantham | 4:52.50 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 21 | Emily INNS | 20 | Altrincham | 4:42.10 |
| 1 | 25 | Annabel IRVINE | 15 | Co Liverpool | 4:40.10 |
| 2 | 29 | Erin JOHNSON | 16 | Nuneaton | 4:39.80 |
| 3 | 34 | Erika SHEPPARD | 17 | Leamington | 4:36.60 |
| 4 | 38 | Kate ROBERTS | 16 | Co Liverpool | 4:30.90 |
| 5 | 36 | Cazia MARTIN | 16 | Co Sheffield | 4:35.42 |
| 6 | 32 | Anabelle KETT | 16 | Co Peterboro | 4:37.10 |
| 7 | 27 | Lilly-Rose UNWIN | 15 | Stockport Mo | 4:40.10 |
| 8 | 23 | Amelia GERRARD | 16 | Co Liverpool | 4:40.70 |
| 9 | 19 | Letian WU | 16 | Trafford Met | 4:42.50 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 22 | Kyra WINTER | 14 | Chesterfield | 4:41.10 |
| 1 | 26 | Elizabeth LYONS | 17 | Co Liverpool | 4:40.10 |
| 2 | 30 | Lacey GRAYSON | 17 | Rotherham Mo | 4:38.98 |
| 3 | 35 | Lois WARD | 14 | Nuneaton | 4:35.70 |
| 4 | 39 | Katherine NOBLE | 17 | Newcastle | 4:29.16 |
| 5 | 37 | Grace TURNER | 18 | Grantham | 4:32.68 |
| 6 | 33 | Molly NORTON | 15 | Co Leeds | 4:36.70 |
| 7 | 28 | Francesca HALLAM-STOTT | 18 | Grantham | 4:40.10 |
| 8 | 24 | Emily ENGLAND-HALL | 13 | Co Leeds | 4:40.54 |
| 9 | 20 | Jessica HUBERY | 15 | Donc Dartes | 4:42.37 |