EVENT 601 Men Open 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 2 | 1 | Daniel Kendall | 15 | Co Ely | 5:14.99 |
| 3 | 3 | James Gourpinar | 14 | Harlow Pen | 5:12.70 |
| 4 | 5 | George Prince | 13 | Hatfield | 5:12.08 |
| 5 | 4 | Corey Hare | 15 | Colchester | 5:12.31 |
| 6 | 2 | Lucas Hartley | 14 | Hatfield | 5:14.90 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 7 | Ben Minister | 15 | Thurrock | 5:11.78 |
| 2 | 9 | Ollie O'Connor | 13 | Putteridge | 5:10.53 |
| 3 | 11 | Jack Barnard | 16 | Potters Bar | 5:09.31 |
| 4 | 13 | Daniel Moyses | 15 | Co Peterboro | 5:07.60 |
| 5 | 12 | Antonio Girolami | 16 | Colchester | 5:08.55 |
| 6 | 10 | Oliver Blight | 15 | Hatfield | 5:10.25 |
| 7 | 8 | William White | 14 | Harlow Pen | 5:10.76 |
| 8 | 6 | Ryan Roberts | 16 | Putteridge | 5:11.82 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 15 | Richard Vanstone | 15 | Chelmsford | 5:06.99 |
| 2 | 17 | Jacob Cowin | 17 | March | 5:01.96 |
| 3 | 19 | Connor Houston | 17 | Deben | 5:01.17 |
| 4 | 21 | Matthew Monie | 16 | Co Cambridge | 5:00.50 |
| 5 | 20 | Jamie Joshua | 15 | Hatfield | 5:00.54 |
| 6 | 18 | Lewis Archer | 24 | Halstead | 5:01.45 |
| 7 | 16 | Harry Stagg | 15 | Basildon Ph | 5:06.43 |
| 8 | 14 | Harrison Shaw | 14 | Flitwick | 5:07.11 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 23 | Daryl Rands | 24 | Colchester | 4:58.31 |
| 2 | 25 | Sandijs Cecins | 14 | Colchester | 4:55.37 |
| 3 | 27 | Nikita Charykin | 15 | Thurrock | 4:53.20 |
| 4 | 29 | Daniel McGuinness | 15 | Basildon Ph | 4:48.15 |
| 5 | 28 | Mattias Morse | 18 | Hemel Hemp | 4:50.61 |
| 6 | 26 | Edward Ormsby | 14 | Co Cambridge | 4:55.14 |
| 7 | 24 | Ethan Howard | 14 | Potters Bar | 4:57.25 |
| 8 | 22 | Archie Chamberlain | 15 | West Suffolk | 4:58.92 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 31 | William Loveman | 21 | Co St Albans | 4:47.20 |
| 2 | 33 | Freddie Laws | 18 | West Norfolk | 4:44.10 |
| 3 | 35 | Joe Cooper | 17 | teamipswich | 4:37.30 |
| 4 | 37 | Nathan Wells | 23 | West Norfolk | 4:19.06 |
| 5 | 36 | Myles Turner | 21 | West Suffolk | 4:27.07 |
| 6 | 34 | Mark Milburn | 16 | Colchester | 4:40.33 |
| 7 | 32 | Sami Zemzami | 16 | Bishop Stort | 4:46.06 |
| 8 | 30 | Joseph Wells | 22 | West Norfolk | 4:47.58 |