EVENT 825 Open/Male 11/14 Yrs 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 2 | Alexander Irish | 12 | Newmarket | 6:07.63 |
| 4 | 4 | Freddie Sargeant | 12 | teamipswich | 6:03.23 |
| 5 | 3 | Harry Larham | 11 | Co Peterboro | 6:06.49 |
| 6 | 1 | John Homan-Daly | 12 | Co St Albans | 6:08.96 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 6 | James Nelson | 12 | Co St Albans | 5:55.58 |
| 2 | 8 | Max Hart | 13 | Verulam | 5:49.87 |
| 3 | 10 | Joseph Payne | 12 | Colchester | 5:49.74 |
| 4 | 12 | David Hoara | 12 | Thurrock | 5:47.81 |
| 5 | 11 | George Connor | 13 | Colchester | 5:48.38 |
| 6 | 9 | Arthur Juviler-Bacon | 12 | Linslade | 5:49.80 |
| 7 | 7 | George Headford | 12 | Basildon Ph | 5:54.00 |
| 8 | 5 | Victor Dryankov | 12 | Thurrock | 5:56.90 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 14 | Marco Soto-Toth | 12 | Co Peterboro | 5:41.63 |
| 2 | 16 | Tobias Watson | 13 | Bo Southend | 5:41.00 |
| 3 | 18 | George Sims | 13 | Hatfield | 5:37.68 |
| 4 | 20 | Apollo Pop | 13 | Chelmsford | 5:36.80 |
| 5 | 19 | Elijah Wilson | 13 | teamipswich | 5:37.30 |
| 6 | 17 | Cody Brigden | 13 | Watford SC | 5:39.73 |
| 7 | 15 | Clark Meanti | 13 | Putteridge | 5:41.14 |
| 8 | 13 | Archie Georgakis | 13 | Basildon Ph | 5:43.03 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 22 | Senan Brullo | 13 | New Hall | 5:34.00 |
| 2 | 24 | Jack Munday | 14 | teamipswich | 5:28.39 |
| 3 | 26 | Leo Sims | 13 | Hatfield | 5:26.08 |
| 4 | 28 | Jude Wankowski | 13 | teamipswich | 5:22.90 |
| 5 | 27 | Noah Conroy | 14 | Bishop Stort | 5:25.80 |
| 6 | 25 | Miles Copping | 14 | Co Cambridge | 5:28.06 |
| 7 | 23 | Fletcher Waugh | 12 | Colchester | 5:29.80 |
| 8 | 21 | Luca Capozzi | 13 | Hemel Hemp | 5:35.06 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 30 | Henry Chaloner | 14 | Biggleswade | 5:21.50 |
| 2 | 32 | Lawrence Taylor | 14 | Co Norwich | 5:19.00 |
| 3 | 34 | Alfie Larham | 14 | Co Peterboro | 5:18.12 |
| 4 | 36 | Finley Burford | 14 | Basildon Ph | 5:15.90 |
| 5 | 35 | Jacob Ure | 14 | Co Peterboro | 5:16.40 |
| 6 | 33 | Harry Clarke | 14 | West Norfolk | 5:18.78 |
| 7 | 31 | Jack Lees | 13 | Epping For't | 5:19.30 |
| 8 | 29 | Johnny McAuley | 13 | Co Peterboro | 5:22.63 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 38 | Taras Boiko | 13 | Bishop Stort | 5:14.70 |
| 2 | 40 | Sebastian Mudge | 14 | Co Peterboro | 5:11.69 |
| 3 | 42 | Riley Allen | 14 | Thurrock | 5:11.40 |
| 4 | 44 | Ashton Hunter | 14 | Co Peterboro | 5:04.80 |
| 5 | 43 | Hugo Koyanagi | 14 | Co St Albans | 5:10.21 |
| 6 | 41 | Aaron Rawnsley | 14 | Harpenden | 5:11.64 |
| 7 | 39 | Benjamin Piscopo | 13 | Co Peterboro | 5:13.40 |
| 8 | 37 | Jesse Knight | 13 | Leiston | 5:14.80 |