EVENT 137 Open/Male 10/14 Yrs 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 3 | 1 | Frederick Frith | 10 | | Buxton | 7:31.90 |
| 4 | 3 | Lucas Cox | 10 | | Repton | 7:02.70 |
| 5 | 2 | Sam Heppleston | 11 | | DerbyPhoenix | 7:16.50 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 0 | 5 | Hugo Harrand | 12 | | Long Eaton | 6:36.66 |
| 1 | 7 | Aden Van Hoorebeek | 13 | | Chesterfield | 6:04.40 |
| 2 | 9 | Fraser Manley | 12 | | Repton | 5:46.50 |
| 3 | 11 | Hector Cox | 12 | | Repton | 5:43.40 |
| 4 | 13 | Leo Hawkins | 13 | | BelperMarlin | 5:38.90 |
| 5 | 12 | Finley Jenkins | 14 | | BelperMarlin | 5:41.50 |
| 6 | 10 | Joel Hubinger | 13 | | Repton | 5:45.00 |
| 7 | 8 | Ayrton Porter | 13 | | Repton | 5:46.70 |
| 8 | 6 | Reuben Canetti | 13 | | Chesterfield | 6:05.00 |
| 9 | 4 | Mason Vickers | 11 | | Long Eaton | 6:58.70 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 0 | 15 | Luke Morley-Smith | 14 | | Swadlincote | 5:36.20 |
| 1 | 17 | James Lee | 12 | | Derby Excel | 5:21.80 |
| 2 | 19 | Arlo Hems Gillson | 13 | | Repton | 5:20.10 |
| 3 | 21 | Oliver Smith | 12 | | Repton | 5:14.90 |
| 4 | 23 | Gabriel Thursfield | 13 | | Repton | 5:07.10 |
| 5 | 22 | Tyler Shaw | 13 | | Derby Excel | 5:14.80 |
| 6 | 20 | Stephen Iankov | 12 | | Repton | 5:16.00 |
| 7 | 18 | Elliott Ratcliffe | 14 | | Etwall | 5:20.30 |
| 8 | 16 | Lincoln Wilson | 12 | | Repton | 5:30.10 |
| 9 | 14 | Thomas Adams | 14 | | Dronfield | 5:37.60 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 0 | 25 | Toby Drayson | 13 | | BelperMarlin | 5:02.30 |
| 1 | 27 | Isaac Ebanks | 14 | | Derby Excel | 4:56.60 |
| 2 | 29 | Finlay Bird | 14 | | Long Eaton | 4:46.20 |
| 3 | 31 | Alex Bates | 14 | | Chesterfield | 4:25.90 |
| 4 | 33 | Austyn Manley | 14 | | Repton | 4:13.00 |
| 5 | 32 | Eden Saint | 14 | | BelperMarlin | 4:25.10 |
| 6 | 30 | Dominik Bartoletti | 14 | | Repton | 4:36.50 |
| 7 | 28 | Seth Hems Gillson | 14 | | Repton | 4:46.91 |
| 8 | 26 | Hayden Hudson | 14 | S14 | Chesterfield | 4:56.90 |
| 9 | 24 | Flynn Chidlow | 14 | | Ripley | 5:05.60 |