EVENT 304 Open/Male 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 1 | Arran Douglas | 12 | Wellington M | 7:02.65 |
| 4 | 3 | William Padmore | 13 | Northgate | 6:51.10 |
| 5 | 2 | Fletcher Harrison | 12 | Northgate | 6:52.23 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 4 | Sebastien De Vere | 13 | Wrekin SC | 6:37.83 |
| 2 | 6 | Adam Rahati | 13 | Wrekin SC | 6:13.54 |
| 3 | 8 | Rory Yarnley | 13 | Northgate | 5:49.20 |
| 4 | 11 | Dylan Thompson | 15 | Wrekin SC | 5:34.29 |
| 5 | 10 | Isaac Pealin | 15 | Oswestry Ott | 5:35.10 |
| 6 | 7 | William Carpenter | 16 | Wellington M | 5:57.60 |
| 7 | 5 | Oliver Hope | 14 | TelfordAqua | 6:30.32 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 14 | Christopher Jones | 19 | Newport | 5:28.84 |
| 2 | 17 | Toby Auckland | 19 | Shrewsbury | 5:16.44 |
| 3 | 19 | Tom Ammundsen | 16 | Market Dray | 5:13.73 |
| 4 | 22 | Sam Good | 15 | Wrekin SC | 5:08.58 |
| 5 | 21 | Hugh Gemmill | 17 | Wrekin SC | 5:12.90 |
| 6 | 18 | Connor Simpson | 16 | Market Dray | 5:14.71 |
| 7 | 16 | Jack Cook | 15 | Northgate | 5:25.90 |
| 8 | 12 | Charlie Scollard-Kerr | 15 | Wrekin SC | 5:34.01 |