EVENT 16 Open/Male 100m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 2 | 1 | Laurence DE ROSE | 9 | Deepings | 2:00.00 |
| 3 | 2 | Alex BARTLE | 10 | Boston | 1:55.77 |
| 4 | 3 | Adam AWAD | 9 | Boston | 1:44.34 |
| 5 | 4 | Zachary SMITH GOMEZ | 10 | Lincoln Vulc | 1:42.47 |
| 6 | 5 | Tom GRIFFIN | 11 | Deepings | 1:41.50 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 6 | Henry SMITH | 12 | Skegness | 1:41.11 |
| 2 | 7 | Edward BIRINY | 11 | Lincoln Vulc | 1:40.00 |
| 3 | 8 | Jack PAIGE | 11 | Deepings | 1:40.00 |
| 4 | 9 | Jack SMITH | 10 | Gainsborough | 1:38.05 |
| 5 | 10 | Arnas MESKAUSKAS | 9 | Louth | 1:35.00 |
| 6 | 11 | Henry LEONARD | 9 | Grantham | 1:32.10 |
| 7 | 12 | Oliver ERSKINE | 13 | Lincoln TSA | 1:31.44 |
| 8 | 13 | Felix THORNDIKE | 9 | Lincoln Vulc | 1:30.50 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 14 | Noah LAWRENCE | 10 | Louth | 1:30.40 |
| 2 | 15 | Harry BIBBY | 9 | Grantham | 1:30.00 |
| 3 | 16 | Oscar BEMBRIDGE | 9 | Grantham | 1:30.00 |
| 4 | 17 | Henry BOWERS | 10 | Grantham | 1:30.00 |
| 5 | 18 | Coen RUCK | 12 | Louth | 1:29.28 |
| 6 | 19 | George DOLAN | 9 | Grantham | 1:29.19 |
| 7 | 20 | Benjamin SHEARN | 12 | Grantham | 1:26.07 |
| 8 | 21 | Oscar DOWNING | 14 | Lincoln TSA | 1:25.00 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 22 | Tommy-Lucas PARKINSON | 11 | Gainsborough | 1:24.50 |
| 2 | 23 | Daniel GODDARD | 11 | Grantham | 1:24.10 |
| 3 | 24 | Rory MACKFALL | 12 | Lincoln Vulc | 1:24.00 |
| 4 | 25 | George BRUMBY | 10 | Gainsborough | 1:23.59 |
| 5 | 26 | Teddy LAWLOR | 11 | Louth | 1:23.20 |
| 6 | 27 | Liam EDMEADES | 10 | Deepings | 1:21.50 |
| 7 | 28 | Cooper SPRING | 13 | Skegness | 1:19.25 |
| 8 | 29 | Tom BARRATT | 11 | Gainsborough | 1:17.50 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 30 | William PENNOCK | 12 | Grantham | 1:17.12 |
| 2 | 31 | Freddie HIRST | 11 | Grantham | 1:16.90 |
| 3 | 32 | Benjamin GODDARD | 13 | Grantham | 1:16.50 |
| 4 | 33 | Damir IVANOVS | 11 | Boston | 1:14.96 |
| 5 | 34 | Bertie ROSE | 12 | Lincoln Vulc | 1:14.30 |
| 6 | 35 | Evan WILSON | 12 | Gainsborough | 1:14.00 |
| 7 | 36 | Elliot GLEAVE | 13 | Grantham | 1:12.83 |
| 8 | 37 | Henry DOLAN | 12 | Grantham | 1:12.30 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 38 | Ethan COUGHLAN | 14 | Lincoln Vulc | 1:12.00 |
| 2 | 39 | Derrin BROCKLEBANK | 12 | Grantham | 1:10.95 |
| 3 | 40 | Arthur ADAMS | 12 | Louth | 1:10.67 |
| 4 | 41 | Benjamin NOAKES | 12 | Louth | 1:10.60 |
| 5 | 42 | Jacob STAPLES | 14 | Lincoln Vulc | 1:10.40 |
| 6 | 43 | Zachary LAWRENCE | 13 | Louth | 1:10.20 |
| 7 | 44 | Bobby THAIN | 15 | Skegness | 1:09.75 |
| 8 | 45 | Albert HAILE | 14 | Louth | 1:09.54 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 46 | Elliot MCWHIRTER | 16 | Lincoln TSA | 1:08.85 |
| 2 | 47 | George LEONARD | 13 | Grantham | 1:07.96 |
| 3 | 48 | Alfie BLADES | 15 | Gainsborough | 1:06.00 |
| 4 | 49 | Yu Ching (Eugene) CHEU | 14 | Grantham | 1:05.30 |
| 5 | 50 | Oscar HE | 13 | Gainsborough | 1:05.10 |
| 6 | 51 | Ollie BLANCHARD | 15 | Skegness | 1:04.70 |
| 7 | 52 | Owen ZHANG | 14 | Gainsborough | 1:02.90 |
| 8 | 53 | Ethan HUNTER | 15 | Lincoln Vulc | 1:02.11 |
| Heat Number - 8 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 55 | Archie FRENCH | 16 | Lincoln Vulc | 1:00.05 |
| 2 | 57 | James THOMAS | 16 | Gainsborough | 58.60 |
| 3 | 59 | Layton ANNISON-SNOWDEN | 16 | Louth | 56.81 |
| 4 | 61 | Ryan NORTON | 18 | Boston | 55.13 |
| 5 | 60 | Joshua HANKS | 16 | Louth | 56.20 |
| 6 | 58 | Luke DAYBELL | 16 | Grantham | 57.34 |
| 7 | 56 | Oliver SHEPHERD | 16 | Deepings | 58.72 |
| 8 | 54 | Dominic MCLAUGHLIN | 15 | Louth | 1:00.32 |