EVENT 401 Boys 10 Yrs/Over 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 1 | Ben CARLYLE | 12 | Grantham | |
| 2 | 2 | Leo BARNETT | 10 | Grantham | |
| 3 | 3 | Arthur BREARLEY-NEWSOM | 11 | Grantham | |
| 4 | 4 | Luca HALLAM | 10 | Grantham | |
| 5 | 5 | Oscar DURANT | 11 | Grantham | |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 6 | Samuel NICHOLS | 10 | Grantham | |
| 2 | 7 | Fabian KOLASA | 11 | Grantham | |
| 3 | 9 | Theo BACON | 12 | Grantham | 6:35.75 |
| 4 | 10 | Luke DAYBELL | 13 | Grantham | 6:05.06 |
| 5 | 11 | Daniel DEGNAN | 14 | Grantham | 5:37.57 |
| 6 | 13 | Jack ZERAVICA | 14 | Grantham | 5:25.52 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 15 | Zach HOPKINSON | 13 | Grantham | 5:03.67 |
| 2 | 17 | Joshua CLARKE | 14 | Grantham | 4:59.29 |
| 3 | 19 | Samuel LEVERIDGE | 16 | Grantham | 4:25.90 |
| 4 | 18 | Owen HATHWAY | 16 | Grantham | 4:26.52 |
| 5 | 16 | Jacob FISH | 13 | Grantham | 5:00.26 |
| 6 | 14 | Ridas RABASAUSKAS | 14 | Grantham | 5:18.72 |