EVENT 905 Open/Male 50m Butterfly - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 2 | Noah HALIFAX | 10 | South Lincs | 41.52 |
| 2 | 4 | Thomas VERE | 12 | South Lincs | |
| 3 | 6 | Siddharth SUTHAN | 12 | Co Lincoln P | |
| 4 | 8 | Seth CLAYTON | 12 | South Lincs | |
| 5 | 7 | Benjamin SHEARN | 12 | Grantham | 40.21 |
| 6 | 5 | Cameron JAMISON | 11 | Lincoln TSA | 42.27 |
| 7 | 3 | Harrison ABLITT | 11 | Co Lincoln P | |
| 8 | 1 | George DOLAN | 10 | Grantham | 42.67 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 10 | Ethan LUCY | 12 | South Lincs | 41.32 |
| 2 | 12 | Cyril BAO | 10 | Grantham | 42.25 |
| 3 | 14 | Derrin BROCKLEBANK | 12 | Grantham | 41.79 |
| 4 | 16 | Hugo BRAILSFORD | 12 | Deepings | 39.05 |
| 5 | 15 | Brody LENTZ | 11 | Louth | 37.42 |
| 6 | 13 | William PENNOCK | 12 | Grantham | |
| 7 | 11 | Liam EDMEADES | 11 | Deepings | 39.69 |
| 8 | 9 | Damir IVANOVS | 11 | Boston | 43.29 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 18 | Benjamin NOAKES | 12 | Louth | 36.49 |
| 2 | 20 | Elliott GLEAVE | 13 | Grantham | |
| 3 | 22 | Oscar WOOD | 13 | Lincoln Vulc | |
| 4 | 24 | Arthur ADAMS | 13 | Louth | |
| 5 | 23 | Malin FYSON | 13 | South Lincs | 35.81 |
| 6 | 21 | Freddie HIRST | 12 | Grantham | 38.02 |
| 7 | 19 | Henry DOLAN | 13 | Grantham | 35.49 |
| 8 | 17 | Joshua FORSYTH | 12 | Lincoln Vulc | 37.73 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 26 | Henry WILLERTON | 13 | Skegness | 35.61 |
| 2 | 28 | George LEONARD | 14 | Grantham | |
| 3 | 30 | Jimmin BAO | 13 | Grantham | 35.44 |
| 4 | 33 | Toby EDMONDSON | 12 | Grantham | 34.48 |
| 5 | 32 | Hoby CARR | 14 | Co Lincoln P | 33.78 |
| 6 | 29 | Samuel GRIFFIN | 14 | Deepings | 34.05 |
| 7 | 27 | Cameron MILNE | 14 | Deepings | |
| 8 | 25 | Oscar HE | 13 | Gainsborough | 34.94 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 35 | Arlo HAMER | 14 | Co Lincoln P | 33.17 |
| 2 | 37 | M PARAPIJONAVICIUS | 13 | Grantham | 34.43 |
| 3 | 39 | Callum LOYNES | 14 | Co Lincoln P | |
| 4 | 41 | Lucas GOODWIN | 15 | Lincoln Vulc | 30.93 |
| 5 | 40 | Cole COOPER | 14 | Co Lincoln P | 32.12 |
| 6 | 38 | Oliver CLARKE | 14 | Deepings | 32.82 |
| 7 | 36 | Leo BARNETT | 14 | Grantham | 33.34 |
| 8 | 34 | Dan PALMER | 13 | Co Lincoln P | 33.58 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 43 | Thomas HILLSON | 13 | Grantham | 33.43 |
| 2 | 45 | Finley WEST | 15 | Co Lincoln P | 31.69 |
| 3 | 48 | Francesco MONACO | 14 | South Lincs | 31.93 |
| 4 | 50 | Cezmi MERMUTLU | 15 | Louth | 30.67 |
| 5 | 49 | Oliver WILKINSON | 14 | Co Lincoln P | 31.68 |
| 6 | 47 | Dominic MCLAUGHLIN | 15 | Louth | 31.88 |
| 7 | 44 | Harry BEASTALL | 15 | Co Lincoln P | 32.20 |
| 8 | 42 | Reid HATCH | 14 | Gainsborough | |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 52 | Kieron TOMS | 16 | Deepings | 30.02 |
| 2 | 54 | Oliver JONES | 17 | Lincoln Vulc | |
| 3 | 56 | Kieran LUCY | 16 | South Lincs | 30.01 |
| 4 | 58 | Matthew TOMPKINSON | 17 | Louth | |
| 5 | 57 | Freddie TRAGNI | 17 | Co Lincoln P | |
| 6 | 55 | Joshua HANKS | 16 | Louth | 28.31 |
| 7 | 53 | Jacob FISH | 17 | Grantham | |
| 8 | 51 | Patrick ADEJUWON | 15 | South Lincs | 29.92 |
| Heat Number - 8 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 63 | Oliver GARNER | 16 | Co Lincoln P | 29.32 |
| 2 | 69 | Jacob HEGG | 16 | Lincoln Vulc | 28.21 |
| 3 | 75 | Richard RUSSELL-CARR | 26 | Co Lincoln P | 27.30 |
| 4 | 81 | Joseph PARNELL | 19 | Co Lincoln P | 26.14 |
| 5 | 78 | Morgan FARRAR | 17 | Co Lincoln P | 26.70 |
| 6 | 72 | Luke DAYBELL | 17 | Grantham | |
| 7 | 66 | Jake ADAMS | 19 | Louth | |
| 8 | 60 | Hayden FIELDS | 19 | Lincoln TSA | |
| Heat Number - 9 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 64 | Robbie DUFF | 15 | Lincoln Vulc | 29.47 |
| 2 | 70 | Riley HAMER | 16 | Co Lincoln P | 29.24 |
| 3 | 76 | Oliver SEALEY | 18 | Louth | 27.61 |
| 4 | 82 | Bradley HOLLAND | 18 | South Lincs | 26.66 |
| 5 | 79 | James DOBNEY | 22 | Grantham | 26.54 |
| 6 | 73 | Ryan NORTON | 19 | Boston | |
| 7 | 67 | Leon BAILEY | 20 | Louth | |
| 8 | 61 | Ben LORD | 21 | Co Lincoln P | |
| Heat Number - 10 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 65 | Oliver SHEPHERD | 17 | Deepings | |
| 2 | 71 | Zach HOPKINSON | 17 | Grantham | |
| 3 | 77 | Daniel HEPPLESTONE | 16 | Co Lincoln P | 28.57 |
| 4 | 83 | Benjamin ROBERTS | 17 | Grantham | 26.00 |
| 5 | 80 | Jamie GREEN | 21 | Co Lincoln P | 26.46 |
| 6 | 74 | Ben CARLYLE | 16 | Grantham | 27.51 |
| 7 | 68 | Benjamin DERBY | 18 | Lincoln Vulc | |
| 8 | 62 | Layton ANNISON-SNOWDEN | 17 | Louth | |