EVENT 101 Mens Open 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | YoB | Club/Country | Time |
| 1 | 1 | Luke Robins | 99 | Millfield | 4:06.04 |
| 2 | 3 | Cameron Croot | 99 | Swansea Aq | 4:05.68 |
| 3 | 5 | James Gillie | 98 | Millfield | 4:05.60 |
| 4 | 7 | Jamie Scholes | 00 | Co Peterboro | 4:04.35 |
| 5 | 6 | Charlie Humphries | 99 | Nova Cent'n | 4:04.47 |
| 6 | 4 | Daniel Leigh | 99 | Co Peterboro | 4:05.62 |
| 7 | 2 | Tony-Joe Trett Oliver | 99 | Mt Kelly | 4:05.85 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | YoB | Club/Country | Time |
| 1 | 9 | Max Murphy | 00 | Co Milton K | 4:02.98 |
| 2 | 11 | Thomas Kingham | 98 | Millfield | 4:02.94 |
| 3 | 13 | Nathan Hughes | 00 | Hatfield | 4:02.01 |
| 4 | 15 | Regan Lloyd | 97 | teamipswich | 4:00.86 |
| 5 | 14 | Harrison Coulter | 99 | Stockport Mo | 4:01.24 |
| 6 | 12 | George Taplin | 99 | Maidenhead | 4:02.94 |
| 7 | 10 | Daniel Davies | 98 | Swansea Aq | 4:02.97 |
| 8 | 8 | Ryan Retson | 00 | F.I.R.S.T. | 4:03.56 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | YoB | Club/Country | Time |
| 1 | 17 | Oliver Tennant | 93 | Swansea Aq | 4:00.66 |
| 2 | 19 | Reece Worth | 96 | Mt Kelly | 4:00.55 |
| 3 | 21 | Daniel Fogg | 87 | Loughboro Un | 3:59.72 |
| 4 | 23 | Thomas Atkinson | 98 | Co Sheffield | 3:58.81 |
| 5 | 22 | Julian Chan Quee Lin | 97 | Mt Kelly | 3:59.31 |
| 6 | 20 | Ben Evans | 97 | Thanet Swim | 4:00.46 |
| 7 | 18 | Kieran Bird | 99 | Bicester | 4:00.62 |
| 8 | 16 | Nathan Wells | 98 | West Norfolk | 4:00.86 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | YoB | Club/Country | Time |
| 1 | 25 | Thomas Howley | 96 | Newcastle | 3:58.21 |
| 2 | 27 | Brodie Williams | 99 | Millfield | 3:58.05 |
| 3 | 29 | Fraser Minnican | 95 | Loughboro Un | 3:57.93 |
| 4 | 31 | Thomas Flaherty | 97 | Co Milton K | 3:57.74 |
| 5 | 30 | Angus Barr | 98 | Eastkilbride | 3:57.89 |
| 6 | 28 | Samuel Budd | 98 | Co Sheffield | 3:57.94 |
| 7 | 26 | Tom Derbyshire | 98 | Royal Wolv | 3:58.06 |
| 8 | 24 | Jamie O'Connor | 99 | Thanet Swim | 3:58.77 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | YoB | Club/Country | Time |
| 1 | 34 | Michael Gunning | 94 | London Aquat | 3:55.00 |
| 2 | 38 | Daniel Jervis | 96 | Swansea Aq | 3:52.21 |
| 3 | 42 | Jay Lelliott | 95 | Bath Univ | 3:48.84 |
| 4 | 46 | Nicholas Grainger | 94 | Co Sheffield | 3:45.89 |
| 5 | 44 | Stephen Milne | 94 | Perth City | 3:48.32 |
| 6 | 40 | Cameron Kurle | 97 | Millfield | 3:51.00 |
| 7 | 36 | Cameron Brown | 96 | Co Newport | 3:53.34 |
| 8 | 32 | Alex Dunk | 95 | Prescot | 3:57.05 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | YoB | Club/Country | Time |
| 1 | 35 | Ieuan Lloyd | 93 | Co Cardiff | 3:53.81 |
| 2 | 39 | Timothy Shuttleworth | 97 | Loughboro Un | 3:52.15 |
| 3 | 43 | Max Litchfield | 95 | Co Sheffield | 3:48.59 |
| 4 | 47 | James Guy | 95 | Millfield | 3:43.75 |
| 5 | 45 | Daniel Wallace | 93 | Warrender Ba | 3:46.15 |
| 6 | 41 | Caleb Hughes | 95 | Loughboro Un | 3:50.44 |
| 7 | 37 | Kyle Chisholm | 97 | Bo Kirklees | 3:52.32 |
| 8 | 33 | Matthew Johnson | 95 | Bath Univ | 3:56.87 |