EVENT 136 Mens Open 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 2 | 1 | Ben PENHALE | 14 | TauntonDeane | 5:04.77 |
| 3 | 2 | Dylan GALLAGHER | 14 | TauntonDeane | 5:03.53 |
| 4 | 3 | Jonah SILK | 14 | Co Bristol | 5:02.70 |
| 5 | 4 | Jack GIBERT | 16 | Co Bristol | 5:01.34 |
| 6 | 5 | Linus LAUNHARDT | 15 | Mt Kelly | 5:00.40 |
| 7 | 6 | George SPENCER | 19 | N Cornwall | 5:00.00 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 7 | Samuel LAWTON | 16 | Co Bristol | 4:58.31 |
| 2 | 8 | Robert WHITTAKER | 16 | Barnstaple | 4:53.10 |
| 3 | 9 | Michal KOTLEWSKI | 23 | Utd Bristol | 4:53.10 |
| 4 | 10 | Christian TAI | 16 | Bourmth Coll | 4:51.88 |
| 5 | 11 | George LEAMAN | 18 | Plymouth Lea | 4:51.18 |
| 6 | 12 | Joseph RUSSELL | 15 | Mt Kelly | 4:50.92 |
| 7 | 13 | James KING | 17 | Weston S M | 4:47.30 |
| 8 | 14 | Dylan HOOD | 16 | Team Bath AS | 4:47.20 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 16 | William ELLINGTON | 14 | Millfield | 4:46.68 |
| 2 | 18 | David MILLER | 18 | Plymouth Lea | 4:45.50 |
| 3 | 20 | Jakob GOODMAN | 17 | Millfield | 4:34.20 |
| 4 | 22 | Brodie WILLIAMS | 18 | Millfield | 4:20.64 |
| 5 | 21 | Ben HARRISON | 17 | Mt Kelly | 4:33.83 |
| 6 | 19 | Lewis SMART | 16 | Mt Kelly | 4:44.25 |
| 7 | 17 | Samuel PECK | 17 | Mt Kelly | 4:46.49 |
| 8 | 15 | Ethan MCNEIL | 15 | Team Bath AS | 4:47.15 |