EVENT 108 Mens Open 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 1 | Joshua Williams | 15 | Wycombe Dist | 4:17.98 |
| 2 | 3 | Jake Moxham | 15 | Co Cambridge | 4:17.71 |
| 3 | 5 | Daniel Johnson | 15 | Royal Wolv | 4:17.53 |
| 4 | 7 | Jevon Penny | 14 | Northampton | 4:17.26 |
| 5 | 6 | Matthew Smith | 15 | Northampton | 4:17.31 |
| 6 | 4 | Timothy Leberl | 15 | Beckenham | 4:17.67 |
| 7 | 2 | Joseph Kingsland | 14 | Nova Cent'n | 4:17.93 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 0 | 9 | Casper Raynard | 15 | Derventio | 4:17.09 |
| 1 | 11 | William Earl | 15 | Co Sheffield | 4:16.86 |
| 2 | 13 | Ellis Stanhope | 15 | Sevenoaks | 4:16.58 |
| 3 | 15 | Lewis Binning | 14 | Romford Town | 4:15.88 |
| 4 | 17 | Charley Langford | 14 | Thanet Swim | 4:15.76 |
| 5 | 16 | Alexander Hindle | 15 | Co Birm'ham | 4:15.84 |
| 6 | 14 | Ryan Wilcox | 15 | Nova Cent'n | 4:16.13 |
| 7 | 12 | Jackson O'Rourke | 15 | Northampton | 4:16.78 |
| 8 | 10 | Oliver Duckworth | 15 | Grimsby AST | 4:16.94 |
| 9 | 8 | Joseph Deighan | 14 | Stockport Mo | 4:17.16 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 0 | 19 | Henry Pearce | 15 | Co Peterboro | 4:15.38 |
| 1 | 21 | Benjamin Foster | 15 | Stockport Mo | 4:15.25 |
| 2 | 23 | Pierce Greening | 14 | Cockermouth | 4:14.31 |
| 3 | 25 | Joseph Russell | 15 | Mt Kelly | 4:12.50 |
| 4 | 27 | Pietro Forconi | 14 | Winchester | 4:09.29 |
| 5 | 26 | Ciaran Thomas | 15 | Newcastle | 4:10.04 |
| 6 | 24 | Samuel Salih | 15 | Co Sheffield | 4:13.46 |
| 7 | 22 | James Cooper | 15 | Basildon Ph | 4:14.96 |
| 8 | 20 | Ewan Wilson | 15 | Co Salford | 4:15.26 |
| 9 | 18 | Thomas Beamer | 15 | Co Leicester | 4:15.68 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 0 | 29 | Jacob Davies | 15 | Co Birm'ham | 4:06.68 |
| 1 | 31 | Jacques Bonsell | 18 | Blackpool Aq | 4:04.63 |
| 2 | 33 | Billy Pettit | 16 | Ellesmere Co | 4:04.37 |
| 3 | 35 | Casey Barrett | 18 | Royal Wolv | 4:04.16 |
| 4 | 37 | Adam Wilson | 16 | Newcastle | 4:04.06 |
| 5 | 36 | Thomas Thornley | 18 | Millfield | 4:04.07 |
| 6 | 34 | Matthew George | 17 | Co Salford | 4:04.32 |
| 7 | 32 | Joel Thompson | 16 | Ellesmere Co | 4:04.59 |
| 8 | 30 | William Martin | 17 | Maxwell | 4:04.72 |
| 9 | 28 | Edward Mildred | 14 | Northampton | 4:07.28 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 0 | 39 | Charlie Poole | 16 | Co Leicester | 4:03.84 |
| 1 | 41 | Archie Plowman | 16 | Northampton | 4:03.66 |
| 2 | 43 | William Bell | 15 | Co Leicester | 4:03.38 |
| 3 | 45 | Ross Hill | 20 | Loughboro Un | 4:02.82 |
| 4 | 47 | Thomas Flower | 18 | RichmondDale | 4:02.71 |
| 5 | 46 | Harry Constantine | 17 | Hatfield | 4:02.82 |
| 6 | 44 | Max Tambling | 18 | Hackney | 4:03.15 |
| 7 | 42 | Harley Beentjes | 17 | Wigan BEST | 4:03.50 |
| 8 | 40 | Myles Robinson-Young | 15 | Co Peterboro | 4:03.69 |
| 9 | 38 | Liam Snook | 19 | Northampton | 4:03.88 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 0 | 50 | William Ryley | 19 | Bath Univ | 4:01.35 |
| 1 | 54 | Jamie Scholes | 17 | Co Peterboro | 4:01.09 |
| 2 | 58 | Max Murphy | 17 | Co Milton K | 3:57.20 |
| 3 | 62 | Lander Hendrickx | 23 | Laqua BEL | 3:54.05 |
| 4 | 66 | Nicholas Grainger | 23 | Co Sheffield | 3:47.86 |
| 5 | 64 | Samuel Budd | 19 | Co Sheffield | 3:50.69 |
| 6 | 60 | Kieran Bird | 18 | Millfield | 3:56.46 |
| 7 | 56 | Nathan Hughes | 17 | Hatfield | 3:59.05 |
| 8 | 52 | Craig Munden | 20 | Loughboro Un | 4:01.23 |
| 9 | 48 | Alexander Bregazzi | 19 | Loughboro Un | 4:02.17 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 0 | 51 | Samuel Osborne | 16 | Co Birm'ham | 4:01.25 |
| 1 | 55 | Ryan Reader | 19 | Derventio | 4:00.59 |
| 2 | 59 | Thomas Howley | 21 | Newcastle | 3:57.01 |
| 3 | 63 | Tobias Robinson | 21 | Loughboro Un | 3:53.28 |
| 4 | 67 | Jay Lelliott | 22 | Co Sheffield | 3:47.48 |
| 5 | 65 | Timothy Shuttleworth | 20 | Loughboro Un | 3:48.53 |
| 6 | 61 | Caleb Hughes | 22 | Loughboro Un | 3:55.71 |
| 7 | 57 | Nathan Wells | 19 | Loughboro Un | 3:57.68 |
| 8 | 53 | Regan Lloyd | 20 | teamipswich | 4:01.11 |
| 9 | 49 | William Foster | 17 | Co Derby | 4:02.09 |