EVENT 204 Mens MC 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 3 | 1 | Bruce Dee | 06 | S6 | Northampton | 7:23.20 |
| 4 | 2 | Sebastian Haregard | 02 | S7 | Sweden | 7:02.43 |
| 5 | 3 | William Whitehead | 05 | S8 | Eckington | 6:50.13 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 0 | 4 | Alexander Hobbs | 05 | S7 | Mt Kelly | 6:44.98 |
| 1 | 5 | Sebastian Williams | 04 | S6 | Mt Kelly | 6:30.48 |
| 2 | 6 | Tilemachos Pantazidis | 04 | S9 | Greece | 6:20.17 |
| 3 | 7 | Sam Downie | 06 | S9 | Musselburgh | 6:15.46 |
| 4 | 8 | F Carcamo Arana | 90 | S6 | Spain | 6:13.64 |
| 5 | 9 | Ahmad Hashad | 00 | S6 | Egypt | 6:10.29 |
| 6 | 10 | Matthew Davies | 04 | S9 | RomseyTotton | 6:09.92 |
| 7 | 11 | Samuel Whearty | 02 | S9 | Colchester | 5:58.79 |
| 8 | 12 | Benjamin Pope | 04 | S8 | Havant & Wat | 5:49.74 |
| 9 | 13 | Leo McCrea | 03 | S6 | Switzerland | 5:49.41 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 0 | 14 | Leo Johnson | 93 | S8 | Out To Swim | 5:48.87 |
| 1 | 15 | Cameron Hemphill | 03 | S10 | Carnegie | 5:47.27 |
| 2 | 16 | Johannes Weinberg | 02 | S11 | Germany | 5:44.27 |
| 3 | 17 | Ethan Naisbitt | 03 | S9 | Pioneer 79 | 5:39.48 |
| 4 | 18 | Patrick Flanagan | 97 | S6 | Ireland | 5:38.73 |
| 5 | 19 | Ahmed Ali | 97 | S6 | Egypt | 5:37.34 |
| 6 | 20 | Marco Meneses | 01 | S11 | Portugal | 5:34.46 |
| 7 | 21 | Gudfinnur Karlsson | 88 | S11 | Iceland | 5:32.86 |
| 8 | 22 | Maximilian Tulloch | 05 | S9 | Chalfont | 5:31.47 |
| 9 | 23 | Bowen Zhang | 00 | S11 | China | 5:30.00 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 0 | 24 | Balthazar Bradshaw | 06 | S10 | Brompton | 5:28.80 |
| 1 | 25 | Sam De Visser | 03 | S9 | Belgium | 5:27.44 |
| 2 | 26 | Luis Sanchez Barajas | 96 | S9 | Mexico | 5:27.17 |
| 3 | 27 | Adam Donnachie | 00 | S8 | Eastkilbride | 5:26.04 |
| 4 | 28 | Reilly Shanahan | 00 | S9 | Shrewsbury | 5:24.84 |
| 5 | 29 | Kyle Hughes | 01 | S9 | WMWX - GBR | 5:24.19 |
| 6 | 30 | Daniel Videira | 92 | S6 | Portugal | 5:24.12 |
| 7 | 31 | Scott Hadley | 98 | S8 | Orion | 5:21.44 |
| 8 | 32 | Xianquan Huang | 99 | S8 | China | 5:21.00 |
| 9 | 33 | Roan Brennan | 06 | S9 | Basildon Ph | 5:18.13 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 0 | 34 | Ricardo Soares | 99 | S8 | Portugal | 5:15.23 |
| 1 | 35 | Joshua Grob | 96 | S8 | Nova Cent'n | 5:11.51 |
| 2 | 36 | Luke Batty | 05 | S9 | Bolton Metro | 5:09.34 |
| 3 | 37 | Ruben Linhares | 97 | S8 | Portugal | 5:07.29 |
| 4 | 38 | Charlie Coulam | 03 | S10 | Bridlington | 5:02.77 |
| 5 | 39 | Cian Henry O'Riordan | 02 | S13 | Ireland | 4:59.31 |
| 6 | 40 | Kaimar Kaldma | 86 | S12 | Estonia | 4:58.05 |
| 7 | 41 | Zhihua Zhou | 93 | S8 | China | 4:55.00 |
| 8 | 42 | Jonathan McGrath | 93 | S8 | Ireland | 4:54.92 |
| 9 | 43 | Tom Piggott | 00 | S10 | Oswestry Ott | 4:54.73 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 0 | 44 | Jieqiu Deng | 98 | S12 | China | 4:52.55 |
| 1 | 45 | Sean O'Riordan | 99 | S13 | Ireland | 4:52.49 |
| 2 | 46 | Mar Gunnarsson | 99 | S11 | Iceland | 4:52.04 |
| 3 | 47 | Michael Jones | 94 | S7 | MANN - GBR | 4:48.19 |
| 4 | 48 | Conor Ballard | 02 | S10 | Leatherhead | 4:47.04 |
| 5 | 49 | Kieran Williams | 04 | S10 | Newquay | 4:46.01 |
| 6 | 50 | James Brown | 02 | S9 | Royal Wolv | 4:45.12 |
| 7 | 51 | Patryk Biskup | 98 | S9 | Poland | 4:45.01 |
| 8 | 52 | Felix-Ulli Fichtelmann | 01 | S9 | Germany | 4:42.92 |
| 9 | 53 | Benjamin Grainger | 03 | S10 | KELW - GBR | 4:41.74 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 0 | 54 | Malte Braunschweig | 00 | S9 | Germany | 4:41.64 |
| 1 | 55 | Jacob Liam Leach | 00 | S9 | COKN - GBR | 4:40.52 |
| 2 | 56 | Taliso Engel | 02 | S13 | Germany | 4:39.53 |
| 3 | 57 | Shamil Shahov | 04 | S13 | Azerbaijan | 4:36.00 |
| 4 | 58 | Thomas Van Wanrooij | 02 | S13 | Netherlands | 4:35.12 |
| 5 | 59 | Carson Sanocki | 99 | S13 | USA | 4:34.04 |
| 6 | 60 | Jarno Thierens | 98 | S10 | Belgium | 4:34.03 |
| 7 | 61 | Jonas Kesnar | 01 | S9 | Czech Rep | 4:33.83 |
| 8 | 62 | Uchu Tomita | 89 | S11 | Japan | 4:33.71 |
| 9 | 63 | Rogier Dorsman | 99 | S11 | Netherlands | 4:33.10 |
| Heat Number - 8 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 0 | 64 | Callum Pearson | 96 | S10 | Hastings | 4:29.78 |
| 1 | 65 | Gino Caetano | 94 | S9 | Portugal | 4:29.73 |
| 2 | 66 | Barry McClements | 01 | S9 | Ireland | 4:29.38 |
| 3 | 67 | Jonathan Booth | 98 | S9 | BOKE - GBR | 4:27.44 |
| 4 | 68 | David Grachat | 87 | S9 | Portugal | 4:26.89 |
| 5 | 69 | Justin Kaps | 01 | S10 | Germany | 4:25.63 |
| 6 | 70 | Oliver Carter | 00 | S10 | WUSX - GBR | 4:21.90 |
| 7 | 71 | Oliver Hynd | 94 | S9 | NOVA - GBR | 4:19.74 |
| 8 | 72 | Lewis White | 00 | S9 | MANN - GBR | 4:11.26 |
| 9 | 73 | Bas Takken | 99 | S10 | Netherlands | 4:03.89 |