EVENT 307 Boys 100m Breaststroke - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 2 | Daniel GODDARD | 8 | Grantham | |
| 2 | 3 | William PENNOCK | 9 | Grantham | |
| 3 | 4 | Oscar CHEN REES | 11 | Grantham | |
| 4 | 5 | Benjamin SHEARN | 9 | Grantham | |
| 5 | 6 | Woody CLARK | 9 | Grantham | 2:23.09 |
| 6 | 7 | Austin CHEN-REES | 10 | Grantham | 2:18.35 |
| 7 | 8 | Benjamin GODDARD | 10 | Grantham | 2:10.28 |
| 8 | 9 | Derrin BROCKLEBANK | 9 | Grantham | 2:06.13 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 10 | Leo BARNETT | 11 | Grantham | 2:03.43 |
| 2 | 11 | Barnaby DURANT | 10 | Grantham | 2:03.09 |
| 3 | 12 | Thomas KINNEAR | 13 | Grantham | 1:55.04 |
| 4 | 13 | Elliot GLEAVE | 10 | Grantham | 1:54.34 |
| 5 | 14 | George LEONARD | 11 | Grantham | 1:50.40 |
| 6 | 15 | Henry DOLAN | 10 | Grantham | 1:47.06 |
| 7 | 16 | A BREARLEY-NEWSOME | 12 | Grantham | 1:44.36 |
| 8 | 17 | Alfie HAIGH | 14 | Grantham | 1:44.29 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 19 | Oscar DURANT | 12 | Grantham | 1:36.70 |
| 2 | 21 | Theo BACON | 13 | Grantham | 1:30.06 |
| 3 | 23 | Jacob FISH | 14 | Grantham | 1:17.28 |
| 4 | 25 | Zach HOPKINSON | 14 | Grantham | 1:12.63 |
| 5 | 24 | Jack ZERAVICA | 15 | Grantham | 1:14.37 |
| 6 | 22 | James NICHOLS | 14 | Grantham | 1:18.90 |
| 7 | 20 | Joel SADLER | 12 | Grantham | 1:35.91 |
| 8 | 18 | Ben CARLYLE | 13 | Grantham | 1:41.39 |