EVENT 309 Mens MC 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 1 | 2 | Samuel Carter | 06 | S10 | Hoddesdon | 8:58.62 |
| 2 | 4 | James Watson | 04 | S9 | Harrogate | 7:56.50 |
| 3 | 6 | Alexander Hobbs | 05 | S7 | Mt Kelly | 7:28.16 |
| 4 | 8 | Benny Romberg | 06 | S10 | Kingston Roy | 6:48.77 |
| 5 | 7 | Sam Downie | 06 | S9 | Musselburgh | 7:11.80 |
| 6 | 5 | Sebastian Williams | 04 | S6 | Barnet Copt | 7:33.45 |
| 7 | 3 | Aiden Watkins | 03 | S6 | Co Manch Aq | 8:06.93 |
| 8 | 1 | James Garry | 02 | S9 | Mildenhall | 9:21.08 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 1 | 10 | Benjamin Pope | 04 | S8 | Havant & Wat | 6:08.81 |
| 2 | 12 | Samuel Whearty | 02 | S9 | Colchester | 5:55.57 |
| 3 | 14 | Owen Say | 01 | S8 | Bracknell | 5:45.15 |
| 4 | 16 | Luke Batty | 05 | S9 | Bolton Metro | 5:25.21 |
| 5 | 15 | Balthazar Bradshaw | 06 | S10 | Chelsea&West | 5:42.20 |
| 6 | 13 | Maximilian Tulloch | 05 | S9 | Chalfont | 5:47.17 |
| 7 | 11 | Leo McCrea | 03 | S6 | Bourmth Coll | 6:08.25 |
| 8 | 9 | Jacob Chambers | 03 | S8 | Co Manch Aq | 6:31.50 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | YoB | Cat | Club/Country | Time |
| 1 | 18 | Dominic Redpath | 02 | S9 | Portsmouth N | 5:05.64 |
| 2 | 20 | James Brown | 02 | S9 | Bilston | 4:53.16 |
| 3 | 22 | Benjamin Grainger | 03 | S10 | Mt Kelly | 4:48.21 |
| 4 | 24 | Oliver Carter | 00 | S10 | Carnegie | 4:27.69 |
| 5 | 23 | Adam Whyborne | 01 | S10 | Billingham | 4:44.95 |
| 6 | 21 | Conor Ballard | 02 | S10 | Leatherhead | 4:50.49 |
| 7 | 19 | Kieran Williams | 04 | S10 | Newquay | 4:54.07 |
| 8 | 17 | Charlie Coulam | 03 | S10 | Bridlington | 5:20.00 |