EVENT 225 Female 16 Yrs/Over 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 2 | Millie Day | 18 | Rushden | 6:33.30 |
| 2 | 4 | Marcie Blackford | 16 | Corby | 6:20.44 |
| 3 | 6 | Nika Buhharova | 16 | Corby | 6:08.10 |
| 4 | 8 | Emily Denton | 17 | Northampton | 5:44.44 |
| 5 | 7 | Charlotte Ellis | 16 | Daventry | 5:53.60 |
| 6 | 5 | Evelyn Coppa | 16 | Corby | 6:20.18 |
| 7 | 3 | Emily Wallace | 16 | Northampton | 6:23.60 |
| 8 | 1 | Frankie Lamont | 17 | Kettering | 6:39.20 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 10 | Eva Gallagher | 17 | Corby | 5:39.40 |
| 2 | 12 | Ella Mae Prior | 18 | Corby | 5:35.18 |
| 3 | 14 | Phebe Adams | 17 | Northampton | 5:21.50 |
| 4 | 16 | Betsy Wizard | 23 | Northampton | 5:01.50 |
| 5 | 15 | Orna Lett | 16 | Northampton | 5:17.19 |
| 6 | 13 | Holly Hayle | 17 | Northampton | 5:31.42 |
| 7 | 11 | Alice Wallinger | 16 | Wellingboro | 5:35.50 |
| 8 | 9 | Maddie Walden | 16 | Northampton | 5:42.00 |