EVENT 202 Boys Open 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 2 | Mason TRAYNOR | 10 | Coalville | 6:17.81 |
| 4 | 4 | Frank BACON | 13 | Braunstone | 5:53.00 |
| 5 | 3 | John GRAHAM-BROWN | 11 | Leic Peng | 6:10.35 |
| 6 | 1 | Austin GRAHAM | 11 | Leic Peng | 6:26.32 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 6 | Jaidan MAPARA | 13 | Leic Sharks | 5:37.96 |
| 2 | 8 | Arthur BLACKLAWS | 13 | Leic Sharks | 5:24.09 |
| 3 | 10 | Maxwell BURDETT | 11 | Leic Peng | 5:13.36 |
| 4 | 12 | Kenny SMITH | 14 | Leic Sharks | 5:08.47 |
| 5 | 11 | Kieren DEXTER | 15 | OadbyWigston | 5:10.22 |
| 6 | 9 | Alexander BLAIR | 14 | Leicester Ne | 5:17.60 |
| 7 | 7 | Andrew BLAIR | 12 | Leicester Ne | 5:24.69 |
| 8 | 5 | Theo BLACK | 13 | Leic Sharks | 5:50.53 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 14 | Freddie BURDETT | 13 | Leic Peng | 5:03.18 |
| 2 | 16 | Harry LUCAS | 13 | Braunstone | 4:57.94 |
| 3 | 18 | Matthew LONGMAN | 16 | Loughborough | 4:53.26 |
| 4 | 20 | William OXLEY | 13 | Braunstone | 4:51.02 |
| 5 | 19 | Joel YATES | 16 | Leicester Ne | 4:53.14 |
| 6 | 17 | Matthew HALL | 17 | Hinckley | 4:55.98 |
| 7 | 15 | Oliver ASHMAN | 13 | Braunstone | 4:59.93 |
| 8 | 13 | Emerson-Blu GUPWELL | 13 | Braunstone | 5:03.23 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 22 | Albert MISIUDA | 16 | Melton M'bry | 4:43.61 |
| 2 | 25 | Harry FLEET | 17 | Market Har | 4:37.50 |
| 3 | 28 | Charlie JAMES | 17 | Market Har | 4:21.68 |
| 4 | 30 | Alex KEEBLE | 19 | Leic Sharks | 4:08.84 |
| 5 | 29 | William POYSER | 18 | Leic Sharks | 4:19.70 |
| 6 | 26 | Henry SCULLY-PROUD | 16 | Loughborough | 4:36.49 |
| 7 | 23 | Jack LLEWELLYN | 16 | Loughborough | 4:42.05 |
| 8 | 21 | James GOODWIN | 18 | OadbyWigston | 4:47.24 |