EVENT 104 Mixed 09 Yrs/Over 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 1 | Freddie HIRST | 10 | Grantham | 7:30.00 |
| 2 | 2 | Hollie-Anne CROOK | 10 | Grantham | 7:30.00 |
| 3 | 3 | Toby EDMONDSON | 10 | Grantham | 7:15.00 |
| 4 | 4 | Markas PARAPIJONAVICIU | 11 | Grantham | 7:04.00 |
| 5 | 5 | Thomas HILLSON | 11 | Grantham | 7:00.49 |
| 6 | 6 | Lucy ABBOTT | 12 | Grantham | 6:34.80 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 7 | George LEONARD | 12 | Grantham | 6:33.80 |
| 2 | 8 | Thomas KINNEAR | 13 | Grantham | 6:30.00 |
| 3 | 9 | Fabian KOLASA | 13 | Grantham | 6:27.69 |
| 4 | 10 | Annabelle JAY | 13 | Grantham | 6:24.96 |
| 5 | 11 | Annie WEBSTER | 12 | Grantham | 6:22.74 |
| 6 | 12 | Elisabeth KINNEAR | 14 | Grantham | 6:20.00 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 13 | Mia PARAPIJONAVICIUTE | 15 | Grantham | 6:15.00 |
| 2 | 14 | Ellena HOWITT | 13 | Grantham | 6:00.19 |
| 3 | 15 | Grace HOWITT | 15 | Grantham | 5:59.42 |
| 4 | 16 | Amy TAYLOR | 13 | Grantham | 5:49.63 |
| 5 | 17 | Lucy WILLATTS | 13 | Grantham | 5:49.10 |
| 6 | 18 | Sophie WARD | 15 | Grantham | 5:45.56 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 20 | Ben CARLYLE | 14 | Grantham | 5:34.02 |
| 2 | 23 | Grace TURNER | 17 | Grantham | 5:07.60 |
| 3 | 25 | Jacob FISH | 15 | Grantham | 4:51.84 |
| 4 | 24 | Daniel DEGNAN | 16 | Grantham | 5:02.43 |
| 5 | 22 | Zach HOPKINSON | 15 | Grantham | 5:09.53 |
| 6 | 19 | Emilie WEBB | 14 | Grantham | 5:45.07 |