EVENT 307 Open/Male 50m Butterfly - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 1 | Joe KHAN | 9 | Berkhamsted | |
| 4 | 3 | Henry MAY | 10 | Linslade | 1:02.38 |
| 5 | 2 | Benjamin CHILDS | 9 | Berkhamsted | |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 2 | 6 | Zachary LUDWELL | 12 | Dunstable | 51.51 |
| 3 | 9 | Kevin IRIMIA | 12 | Bletchley | 46.95 |
| 4 | 11 | Adam HANIF | 11 | Team Luton | 44.34 |
| 5 | 10 | Elijah POWELL | 12 | Linslade | 44.92 |
| 6 | 7 | Elijah UNSWORTH | 10 | Team Luton | 48.90 |
| 7 | 4 | Philippe MARCELO | 10 | Dunstable | 54.36 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 14 | Trey BEDEAU | 12 | Bletchley | 42.23 |
| 2 | 16 | Sebastian WICKES | 12 | West Suffolk | 39.96 |
| 3 | 19 | Soufian ABDELRAZEK | 12 | St Ives | 38.42 |
| 4 | 21 | Jacob KENNEDY | 14 | Linslade | 38.14 |
| 5 | 20 | Oliver CREASY | 13 | West Suffolk | 38.30 |
| 6 | 17 | Myles BURRIDGE | 11 | St Ives | 38.79 |
| 7 | 15 | Oliver GRZEDA | 15 | Dunstable | 41.08 |
| 8 | 13 | William MACKIE | 11 | Hitchin | 42.26 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 24 | Finley TERRY | 13 | St Ives | 36.80 |
| 2 | 27 | Marcus XU | 13 | Linslade | 35.50 |
| 3 | 31 | Alexander HOWARD | 16 | Berkhamsted | 32.99 |
| 4 | 33 | Felix GUY-PINKNEY | 14 | St Ives | 32.53 |
| 5 | 32 | Samuel CHILDS | 12 | Berkhamsted | 32.90 |
| 6 | 30 | Dewi FORDYCE | 12 | Berkhamsted | 34.13 |
| 7 | 26 | Arthur JUVILER-BACON | 10 | Linslade | 35.84 |
| 8 | 22 | Methuselah MAMMO | 15 | Berkhamsted | 37.72 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 36 | Joseph FINNERTY | 17 | Linslade | 30.99 |
| 2 | 38 | Elijah FISHER | 15 | Linslade | 30.25 |
| 3 | 39 | Oscar MCKERN | 16 | Verulam | 29.03 |
| 4 | 41 | Arthur SMART | 23 | West Suffolk | 27.30 |
| 5 | 40 | George EVERETT | 16 | West Suffolk | 28.98 |
| 6 | 42 | Cem ADALI | 16 | Verulam | 29.33 |
| 7 | 37 | Calum WU | 16 | Verulam | 30.98 |
| 8 | 34 | Charles HALLAM | 12 | Harpenden | 31.90 |