EVENT 132 Women 15 Yrs/Over 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 2 | Romilly Marks | 15 | Newmarket | 5:30.65 |
| 2 | 4 | Elise Delapperall | 15 | Thurrock | 5:28.08 |
| 3 | 6 | Katie Maloney | 24 | Co Norwich | 5:26.69 |
| 4 | 8 | Macy Dexter | 15 | Co Cambridge | 5:24.30 |
| 5 | 7 | Isabella Porzio | 17 | Putteridge | 5:25.97 |
| 6 | 5 | Molly Redgrave | 17 | Colchester | 5:27.40 |
| 7 | 3 | Isabelle Barber | 15 | Stowmarket | 5:28.92 |
| 8 | 1 | Anna-Lucia Fenner | 15 | Basildon Ph | 5:32.02 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 10 | Cerys Williams | 17 | West Suffolk | 5:23.14 |
| 2 | 12 | Katie Andrews | 17 | Norwich Swan | 5:22.50 |
| 3 | 14 | Gracie Trotter | 18 | Leighton Buz | 5:19.61 |
| 4 | 16 | Francesca Key | 16 | Thurrock | 5:18.82 |
| 5 | 15 | Charlotte Williams | 15 | Hatfield | 5:19.01 |
| 6 | 13 | Jessica Mahoney | 16 | Co Peterboro | 5:20.91 |
| 7 | 11 | Morgan Allan | 18 | Modernian | 5:22.69 |
| 8 | 9 | Anna Fallon | 18 | Team Luton | 5:24.00 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 18 | Leah Wightman | 16 | West Norfolk | 5:17.30 |
| 2 | 20 | Megan Pye | 19 | Co Norwich | 5:15.10 |
| 3 | 22 | Ciara Wookey | 17 | Colchester | 5:10.32 |
| 4 | 24 | Matilda Ransome | 15 | Co Cambridge | 5:05.50 |
| 5 | 23 | Olivia Lee | 17 | Co Peterboro | 5:08.34 |
| 6 | 21 | Madelyn Latimer-Hicks | 17 | St Felix Sch | 5:14.21 |
| 7 | 19 | Hannah Willis | 16 | Co Peterboro | 5:17.22 |
| 8 | 17 | Charlotte Tree | 17 | Colchester | 5:18.67 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 26 | Matilda Bogle | 15 | teamipswich | 5:05.04 |
| 2 | 28 | Tia Gardiner | 19 | Basildon Ph | 5:04.83 |
| 3 | 30 | Harriet Salisbury | 17 | Co Peterboro | 5:00.56 |
| 4 | 32 | Ellie Wheeler | 19 | Basildon Ph | 4:50.75 |
| 5 | 31 | Ruby Wheeler | 15 | Basildon Ph | 4:58.90 |
| 6 | 29 | Charlotte White | 16 | West Suffolk | 5:04.00 |
| 7 | 27 | Holly Lamb | 16 | Basildon Ph | 5:04.88 |
| 8 | 25 | Zara Keegan | 19 | Co Cambridge | 5:05.22 |