EVENT 410 Open/Male 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 2 | Jack WADE | 13 | Co Leeds | 5:33.48 |
| 4 | 4 | Edward ROSE | 13 | Rotherham Mo | 5:22.80 |
| 5 | 3 | Samuel HIGGINBOTTOM | 13 | Lancaster | 5:32.64 |
| 6 | 1 | Ashton HUNTER | 13 | Co Peterboro | 5:36.40 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 7 | Daniel FRENCH | 14 | Wirral Metro | 5:20.50 |
| 1 | 9 | Kameron BAKER | 14 | Co Peterboro | 5:20.05 |
| 2 | 11 | Edward GREGORY | 13 | Nova Cent'n | 5:19.30 |
| 3 | 13 | Thomas RICKELS | 14 | Co Liverpool | 5:15.70 |
| 4 | 15 | Lewis HALL | 14 | KingstonHull | 5:14.50 |
| 5 | 14 | Zachary PISCOPO | 14 | Co Peterboro | 5:15.34 |
| 6 | 12 | Leo LI | 13 | Co Leeds | 5:17.60 |
| 7 | 10 | Jude NEWEY-KEANE | 14 | Co Birm'ham | 5:19.50 |
| 8 | 8 | Oliver ATHA | 14 | Co Leeds | 5:20.45 |
| 9 | 5 | Oscar FOCHT | 13 | KingstonHull | 5:21.40 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 18 | Jacob FISH | 16 | Grantham | 4:57.80 |
| 1 | 22 | Leroy SHIH | 15 | Co Birm'ham | 4:54.60 |
| 2 | 26 | Kian LEE | 17 | Co Peterboro | 4:52.60 |
| 3 | 30 | Frank LAMB | 16 | Co Peterboro | 4:48.90 |
| 4 | 34 | Kaiden HITCHINS | 15 | Co Birm'ham | 4:43.70 |
| 5 | 32 | Lachlan MUNRO | 18 | Bo Kirklees | 4:46.80 |
| 6 | 28 | Alfie OWEN | 16 | Wigan BEST | 4:49.14 |
| 7 | 24 | Csanad REHUS | 16 | Co Peterboro | 4:54.20 |
| 8 | 20 | Patrick O'HARA | 15 | Co Leeds | 4:56.90 |
| 9 | 16 | Theo GILHAM | 14 | Nova Cent'n | 5:14.30 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 19 | Samuel HILL | 16 | Co Leeds | 4:57.70 |
| 1 | 23 | Josh DRURY-TEW | 16 | Co Birm'ham | 4:54.50 |
| 2 | 27 | Charlie ROUNCE | 18 | Leamington | 4:49.90 |
| 3 | 31 | Arthur OWENS | 16 | Co Leeds | 4:48.30 |
| 4 | 36 | Dominic SIMPSON | 19 | Nuneaton | 4:37.70 |
| 5 | 33 | Patrick NEILL | 17 | Co Leeds | 4:46.11 |
| 6 | 29 | Kieran NG | 15 | Co Peterboro | 4:49.10 |
| 7 | 25 | Mathew BRADLEY | 19 | Cleethorpes | 4:53.30 |
| 8 | 21 | Lewis DICKINSON | 17 | Nuneaton | 4:54.80 |
| 9 | 17 | George HARRISON | 14 | KingstonHull | 5:03.70 |