EVENT 305 Open/Male 100m Backstroke - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 2 | Kai BHATT | 12 | Dunstable | |
| 2 | 4 | Harry MAKIN | 10 | Dunstable | |
| 3 | 6 | Noah HOLLIS | 12 | Verulam | 2:06.93 |
| 4 | 8 | Carter HANSON | 10 | St Ives | 1:54.86 |
| 5 | 7 | Dexter CLARKE | 9 | Verulam | 2:06.32 |
| 6 | 5 | Benjamin CHILDS | 9 | Berkhamsted | 2:08.51 |
| 7 | 3 | Kan Kline GUIA | 9 | Team Luton | |
| 8 | 1 | Ethan TREW | 10 | Dunstable | |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 10 | Luca JONES | 10 | St Ives | 1:42.45 |
| 2 | 12 | Evan CLARKE | 11 | Verulam | 1:38.46 |
| 3 | 15 | Sebastian TERNOUTH | 10 | Verulam | 1:34.76 |
| 4 | 17 | Jaiden AMUSA | 11 | Team Luton | 1:32.40 |
| 5 | 16 | Cayden GALLOWAY | 12 | Berkhamsted | 1:34.43 |
| 6 | 14 | Tyler LAVENDER | 12 | Team Luton | 1:36.00 |
| 7 | 11 | Samuel MAMMO | 11 | Berkhamsted | 1:41.97 |
| 8 | 9 | William HORTON | 13 | Dunstable | 1:53.42 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 19 | Thomas EVANS | 11 | Verulam | 1:29.81 |
| 2 | 21 | Jack MAY | 13 | Linslade | 1:25.64 |
| 3 | 23 | Soufian ABDELRAZEK | 12 | St Ives | 1:24.95 |
| 4 | 28 | Finley TERRY | 13 | St Ives | 1:21.85 |
| 5 | 26 | Luke TRULL | 13 | Dunstable | 1:23.11 |
| 6 | 22 | Wai Chun LAU | 12 | Verulam | 1:25.58 |
| 7 | 20 | Luke THICKENS | 12 | Linslade | 1:28.10 |
| 8 | 18 | Elijah POWELL | 12 | Linslade | 1:32.26 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 30 | Tate TAYLOR | 13 | St Ives | 1:19.67 |
| 2 | 33 | James EVERETT | 14 | West Suffolk | 1:18.66 |
| 3 | 35 | Dewi FORDYCE | 12 | Berkhamsted | 1:17.39 |
| 4 | 37 | David KANDELAKI | 13 | Linslade | 1:12.19 |
| 5 | 36 | Benjamin MELLORS | 14 | Verulam | 1:16.24 |
| 6 | 34 | Samuel CHILDS | 12 | Berkhamsted | 1:18.41 |
| 7 | 32 | Marcus XU | 13 | Linslade | 1:19.52 |
| 8 | 29 | Arthur JUVILER-BACON | 10 | Linslade | 1:20.40 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 39 | Harry VIDAL-GREENWOOD | 13 | West Suffolk | 1:10.11 |
| 2 | 41 | Calum WU | 16 | Verulam | 1:08.07 |
| 3 | 45 | Oscar MCKERN | 16 | Verulam | 1:06.82 |
| 4 | 44 | Harry FORSYTH | 18 | Linslade | 1:04.63 |
| 5 | 43 | Joseph FINNERTY | 17 | Linslade | 1:06.05 |
| 6 | 42 | George EVERETT | 16 | West Suffolk | 1:07.68 |
| 7 | 40 | Ewan GOTHARD | 16 | Linslade | 1:09.38 |
| 8 | 38 | Elijah FISHER | 15 | Linslade | 1:10.16 |