EVENT 204 Open/Male 100m Breaststroke - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 2 | Daniel Bywater | 16 | | Bramcote | 1:13.79 |
| 2 | 4 | Matteo Monaco | 16 | | South Lincs | 1:13.00 |
| 3 | 6 | Peter Nightingale | 15 | | Co Leicester | 1:12.80 |
| 4 | 8 | Archie Pettinger | 15 | | Worksop | 1:12.04 |
| 5 | 7 | James Thomas | 15 | | Gainsborough | 1:12.69 |
| 6 | 5 | Matthew Pegg | 16 | | Etwall | 1:12.91 |
| 7 | 3 | Theo Gilham | 14 | | Nova Cent'n | 1:13.61 |
| 8 | 1 | Owen Johnson | 17 | SB9 | Repton | 1:18.90 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 10 | Matthew Tompkinson | 16 | | Louth | 1:11.85 |
| 2 | 12 | Oliver Dovey | 15 | | Corby | 1:11.79 |
| 3 | 14 | Hayden Hudson | 15 | SB14 | Chesterfield | 1:11.38 |
| 4 | 16 | Riley Hamer | 15 | | Co Lincoln P | 1:11.21 |
| 5 | 15 | Thomas Collins | 15 | | Bassetlaw SS | 1:11.26 |
| 6 | 13 | Seth Hems Gillson | 15 | | Repton | 1:11.40 |
| 7 | 11 | Brodie Butlin | 16 | | Sutton | 1:11.80 |
| 8 | 9 | Stephen Iankov | 13 | | Repton | 1:11.96 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 18 | Edward Oscroft | 16 | | Northampton | 1:11.00 |
| 2 | 20 | Finlay Underwood | 16 | | Rushden | 1:10.20 |
| 3 | 22 | Samuel Green | 15 | | Bassetlaw SS | 1:09.63 |
| 4 | 24 | James Nightingale | 15 | | Co Leicester | 1:09.20 |
| 5 | 23 | Jake Battle | 14 | | Repton | 1:09.25 |
| 6 | 21 | Arthur Blacklaws | 15 | | Co Leicester | 1:09.80 |
| 7 | 19 | Maxwell Burdett | 13 | | Co Leicester | 1:10.48 |
| 8 | 17 | Joshua Chirita | 16 | | Repton | 1:11.06 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 28 | Mark Khametov | 17 | | Kettering | 1:08.20 |
| 2 | 34 | Finlay Gibson | 17 | | Loughborough | 1:06.79 |
| 3 | 40 | Adam Metcalf | 24 | | Loughborough | 1:04.32 |
| 4 | 46 | Josh Mitchell-Storey | 19 | | Lboro Uni | 1:03.20 |
| 5 | 43 | Oliver Caddick | 20 | | Lboro Uni | 1:03.90 |
| 6 | 37 | Paul Page | 18 | | Hinckley | 1:05.83 |
| 7 | 31 | Noah De N'Yeurt | 18 | | Lboro Uni | 1:07.30 |
| 8 | 25 | Jack Smith | 15 | | Co Leicester | 1:08.44 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 29 | Niklas Saukko-Paavola | 17 | | Leic Sharks | 1:07.89 |
| 2 | 35 | Joseph Wright | 16 | | Chesterfield | 1:06.23 |
| 3 | 41 | Aman Thethy | 17 | | Rushden | 1:04.31 |
| 4 | 47 | Tyler Tombs | 20 | | Nova Cent'n | 1:02.17 |
| 5 | 44 | Caleb O'Brien | 24 | | Corby | 1:03.75 |
| 6 | 38 | Eden Saint | 15 | | Derby Excel | 1:05.57 |
| 7 | 32 | Michael Grachev | 20 | | Uni of Nott | 1:07.00 |
| 8 | 26 | Joshua Yip | 18 | | Uni of Nott | 1:08.31 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 30 | Morgan Farrar | 16 | | Co Lincoln P | 1:07.80 |
| 2 | 36 | Austyn Manley | 15 | | Repton | 1:06.18 |
| 3 | 42 | Benjamin Roberts | 16 | | Grantham | 1:04.20 |
| 4 | 48 | William Tonks | 17 | | Repton | 59.80 |
| 5 | 45 | Jeremiah Carnegie | 16 | | Repton | 1:03.30 |
| 6 | 39 | Aryan Nath | 16 | | Corby | 1:05.30 |
| 7 | 33 | Zachary Drayson | 16 | | Derby Excel | 1:06.84 |
| 8 | 27 | Zach Hopkinson | 16 | | Grantham | 1:08.30 |