EVENT 723 Boy 11/14 Yrs 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 1 | Elliot Hall | 12 | Bishop Stort | 5:33.81 |
| 4 | 3 | Oliver Meier | 12 | Modernian | 5:22.47 |
| 5 | 2 | Orlando Whiting | 12 | St Felix Sch | 5:24.20 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 4 | Philip Spalding | 12 | Putteridge | 5:17.80 |
| 2 | 6 | Kai Patel | 12 | Thurrock | 5:15.85 |
| 3 | 8 | Luke Owens | 12 | Putteridge | 5:15.30 |
| 4 | 10 | Anthony Ganchev | 13 | Basildon Ph | 5:09.91 |
| 5 | 9 | William Hughes | 12 | Basildon Ph | 5:10.88 |
| 6 | 7 | Kian Ptolomey | 12 | Putteridge | 5:15.30 |
| 7 | 5 | Niccolo Camilotti | 12 | Hatfield | 5:17.70 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 12 | Sam Jackson | 13 | Deben | 5:08.60 |
| 2 | 14 | Perrin Ma | 11 | Hatfield | 5:07.80 |
| 3 | 16 | Tyler Stone | 12 | Co Norwich | 5:07.50 |
| 4 | 18 | Isaac Buchan | 13 | Co Norwich | 5:05.60 |
| 5 | 17 | Oscar Hunter | 13 | Norwich Swan | 5:06.15 |
| 6 | 15 | Brandon Crees | 11 | Basildon Ph | 5:07.79 |
| 7 | 13 | Lucas Deans | 13 | Chelmsford | 5:08.51 |
| 8 | 11 | Joe Kaye | 13 | Hatfield | 5:08.70 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 20 | Oliver Fenwick | 13 | Team Luton | 5:04.49 |
| 2 | 22 | Will Riley | 13 | teamipswich | 5:01.60 |
| 3 | 24 | Evan Larthe | 13 | Basildon Ph | 5:00.76 |
| 4 | 26 | Dylan Davenport | 13 | Bishop Stort | 4:59.30 |
| 5 | 25 | Dmitrijs Gracovs | 13 | Harlow Pen | 4:59.75 |
| 6 | 23 | Daniel Andrews | 13 | Halstead | 5:01.28 |
| 7 | 21 | Alexander Gaydon | 12 | teamipswich | 5:02.20 |
| 8 | 19 | Harry Bird | 13 | Putteridge | 5:05.34 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 28 | Jamie Wilson | 13 | West Norfolk | 4:58.98 |
| 2 | 30 | Csanad Rehus | 13 | Co Peterboro | 4:55.69 |
| 3 | 32 | Jude Gunner | 13 | St Felix Sch | 4:48.82 |
| 4 | 34 | Naim Harvey | 14 | Basildon Ph | 4:48.27 |
| 5 | 33 | Hugo Raubitschek-Smith | 14 | Hatfield | 4:48.29 |
| 6 | 31 | Harry Phelan | 13 | Basildon Ph | 4:50.17 |
| 7 | 29 | Tobi Olajide | 13 | Thurrock | 4:58.76 |
| 8 | 27 | Jacob Bacon | 12 | Co Peterboro | 4:59.20 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 36 | Louis Robson | 13 | Co St Albans | 4:47.31 |
| 2 | 38 | Ernest Juverdeanu | 14 | Chelmsford | 4:44.03 |
| 3 | 40 | Ethan Thorpe | 13 | Basildon Ph | 4:42.20 |
| 4 | 42 | Daniel Williams | 14 | Hatfield | 4:39.76 |
| 5 | 41 | Ben Every | 14 | St Felix Sch | 4:41.70 |
| 6 | 39 | Remi-Maysen Keane | 14 | Basildon Ph | 4:42.52 |
| 7 | 37 | Jack Friedlein | 14 | Maldon Shark | 4:45.85 |
| 8 | 35 | Harry Alexander | 14 | teamipswich | 4:47.81 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 44 | Jamie Comitti | 13 | Basildon Ph | 4:37.04 |
| 2 | 46 | Robert Fenner | 14 | Basildon Ph | 4:32.03 |
| 3 | 48 | Massimo Girolami | 14 | Colchester | 4:29.70 |
| 4 | 50 | Alex Harrop | 14 | teamipswich | 4:25.41 |
| 5 | 49 | Orlando Dearing | 14 | Co Peterboro | 4:26.90 |
| 6 | 47 | Daniel Belsey | 14 | Hatfield | 4:31.70 |
| 7 | 45 | Oscar Winterburn | 14 | teamipswich | 4:35.01 |
| 8 | 43 | Albert Orley | 14 | Braintree | 4:37.94 |