EVENT 28 Open/Male 100m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 2 | 1 | George OLA | 10 | Lincoln TSA | 2:19.21 |
| 3 | 2 | Alex BARTLE | 10 | Boston | 2:05.41 |
| 4 | 4 | Edward BIRINY | 11 | Lincoln Vulc | 2:00.00 |
| 5 | 5 | Arnas MESKAUSKAS | 9 | Louth | 1:58.00 |
| 6 | 6 | Danielius MIEZETIS | 11 | Boston | 1:57.73 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 7 | James NICASSIO | 11 | Louth | 1:55.23 |
| 2 | 8 | Ciaran-James WESTERBY | 11 | Louth | 1:54.02 |
| 3 | 9 | Finley MARSH-DEAN | 11 | Louth | 1:50.00 |
| 4 | 10 | Albie WILSON | 9 | Deepings | 1:47.88 |
| 5 | 11 | Benjamin BROWN | 10 | Deepings | 1:45.50 |
| 6 | 12 | Rory FALCONER | 11 | Deepings | 1:44.00 |
| 7 | 13 | Oliver PYGOTT-HAMMOND | 10 | Grantham | 1:43.92 |
| 8 | 14 | Henry LEONARD | 9 | Grantham | 1:42.61 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 15 | Noah LAWRENCE | 10 | Louth | 1:42.47 |
| 2 | 16 | Teddy LAWLOR | 11 | Louth | 1:40.78 |
| 3 | 17 | Ethan PEART | 10 | Deepings | 1:40.50 |
| 4 | 18 | Coen RUCK | 12 | Louth | 1:39.56 |
| 5 | 19 | Logan SHARPE | 12 | Lincoln Vulc | 1:38.43 |
| 6 | 20 | George DOLAN | 9 | Grantham | 1:36.69 |
| 7 | 21 | Evan WILSON | 12 | Gainsborough | 1:35.00 |
| 8 | 22 | Hayden WHITTAKER | 12 | Louth | 1:34.94 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 23 | Cooper SPRING | 13 | Skegness | 1:33.17 |
| 2 | 24 | George WHITE | 12 | Louth | 1:32.16 |
| 3 | 25 | Louis WRIGHT | 12 | Grantham | 1:31.82 |
| 4 | 26 | Bertie ROSE | 12 | Lincoln Vulc | 1:30.03 |
| 5 | 27 | William PENNOCK | 12 | Grantham | 1:29.12 |
| 6 | 28 | Damir IVANOVS | 11 | Boston | 1:28.85 |
| 7 | 29 | Henry EVANS | 12 | Louth | 1:28.75 |
| 8 | 30 | Toby BROWN | 13 | Deepings | 1:27.14 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 31 | Hugo BRAILSFORD | 12 | Deepings | 1:25.17 |
| 2 | 32 | Freddie HIRST | 11 | Grantham | 1:24.18 |
| 3 | 33 | Oscar WOOD | 13 | Lincoln Vulc | 1:23.51 |
| 4 | 34 | Zachary LAWRENCE | 13 | Louth | 1:23.41 |
| 5 | 35 | Ethan COUGHLAN | 14 | Lincoln Vulc | 1:22.74 |
| 6 | 36 | Albert HAILE | 14 | Louth | 1:22.41 |
| 7 | 37 | Henry DOLAN | 12 | Grantham | 1:22.15 |
| 8 | 38 | Samuel GRIFFIN | 13 | Deepings | 1:22.05 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 39 | Derrin BROCKLEBANK | 12 | Grantham | 1:21.77 |
| 2 | 40 | Elliot GLEAVE | 13 | Grantham | 1:20.98 |
| 3 | 41 | Henry WILLERTON | 12 | Skegness | 1:19.99 |
| 4 | 42 | Yu Ching (Eugene) CHEU | 14 | Grantham | 1:17.86 |
| 5 | 43 | Toby EDMONDSON | 11 | Grantham | 1:17.20 |
| 6 | 44 | Oscar HE | 13 | Gainsborough | 1:15.25 |
| 7 | 45 | Thomas HILLSON | 12 | Grantham | 1:15.12 |
| 8 | 46 | Reid HATCH | 13 | Gainsborough | 1:13.42 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 48 | Oliver CLARKE | 13 | Deepings | 1:11.27 |
| 2 | 50 | Chris WILLERTON | 41 | Skegness | 1:08.25 |
| 3 | 52 | Archie FRENCH | 16 | Lincoln Vulc | 1:07.56 |
| 4 | 54 | Ryan NORTON | 18 | Boston | 1:03.32 |
| 5 | 53 | Luke DAYBELL | 16 | Grantham | 1:07.05 |
| 6 | 51 | Oliver SHEPHERD | 16 | Deepings | 1:07.59 |
| 7 | 49 | Cezmi MERMUTLU | 15 | Louth | 1:08.38 |
| 8 | 47 | Ethan HUNTER | 15 | Lincoln Vulc | 1:11.66 |