| Heat Number - 1 | |||||
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 1 | Honey FLOWER | 12 | Grantham | |
| 4 | 4 | Olivia CHARITY | 14 | Grantham | 3:46.76 |
| 5 | 6 | Octavia SHEARN | 14 | Grantham | 3:19.62 |
| Heat Number - 2 | |||||
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 7 | Isabelle CLAYTON | 14 | Grantham | 3:16.81 |
| 2 | 9 | Lucy ABBOTT | 14 | Grantham | 3:09.18 |
| 3 | 12 | Lucy WILLATTS | 15 | Grantham | 2:41.08 |
| 4 | 14 | Chloe HOPKINSON | 21 | Grantham | 2:32.49 |
| 5 | 13 | Emily TALKES | 14 | Grantham | 2:39.69 |
| 6 | 11 | Ellena HOWITT | 15 | Grantham | 2:47.93 |
| 7 | 8 | Hollie-Ann CROOK | 12 | Grantham | 3:14.01 |