EVENT 403 Mixed 100m Butterfly - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 1 | George DOLAN | 9 | Grantham | |
| 2 | 2 | Cyril BAO | 9 | Grantham | |
| 3 | 3 | Hannah EXLEY | 11 | Grantham | 2:10.00 |
| 4 | 4 | Gracie PAYNE | 12 | Grantham | 2:00.00 |
| 5 | 5 | Abigail TAYLOR | 11 | Grantham | 1:59.00 |
| 6 | 6 | Elliot GLEAVE | 12 | Grantham | 1:57.73 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 7 | Emily CLAYTON | 11 | Grantham | 1:57.29 |
| 2 | 8 | Evelyn NICHOLLS | 12 | Grantham | 1:55.00 |
| 3 | 9 | Francesca WESTON | 10 | Grantham | 1:55.00 |
| 4 | 10 | William PENNOCK | 11 | Grantham | 1:50.00 |
| 5 | 11 | Olivia CHARITY | 13 | Grantham | 1:50.00 |
| 6 | 12 | Madeline SURTEES | 13 | Grantham | 1:49.49 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 13 | Elizabeth JONES | 15 | Grantham | 1:41.20 |
| 2 | 14 | Emmeline GLEAVE | 10 | Grantham | 1:37.58 |
| 3 | 15 | Octavia SHEARN | 13 | Grantham | 1:35.30 |
| 4 | 16 | Ella KHAMA | 11 | Grantham | 1:35.10 |
| 5 | 17 | Benjamin SHEARN | 11 | Grantham | 1:35.00 |
| 6 | 18 | Isabelle CLAYTON | 13 | Grantham | 1:31.80 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 19 | Derrin BROCKLEBANK | 11 | Grantham | 1:30.71 |
| 2 | 20 | Henry DOLAN | 12 | Grantham | 1:29.42 |
| 3 | 21 | Freddie HIRST | 11 | Grantham | 1:28.98 |
| 4 | 22 | Ava-Grace GREGORY | 13 | Grantham | 1:27.56 |
| 5 | 23 | Luke DAYBELL | 16 | Grantham | 1:27.17 |
| 6 | 24 | Mia PARAPIJONAVICIUTE | 16 | Grantham | 1:26.36 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 25 | George LEONARD | 13 | Grantham | 1:25.19 |
| 2 | 26 | Thomas KINNEAR | 14 | Grantham | 1:24.31 |
| 3 | 27 | Lexie SHEWAN | 15 | Grantham | 1:22.34 |
| 4 | 28 | Isobel ALLSOP | 15 | Grantham | 1:21.89 |
| 5 | 29 | Grace HOWITT | 16 | Grantham | 1:20.93 |
| 6 | 30 | Lucy ABBOTT | 13 | Grantham | 1:20.92 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 31 | Jessica - Rose DAVISON | 16 | Grantham | 1:19.90 |
| 2 | 32 | Lizzy LERESCHE HANDS | 14 | Grantham | 1:19.36 |
| 3 | 33 | Yu Ching (Eugene) CHEU | 14 | Grantham | 1:18.65 |
| 4 | 34 | Toby EDMONDSON | 11 | Grantham | 1:17.77 |
| 5 | 35 | Markas PARAPIJONAVICIU | 12 | Grantham | 1:17.47 |
| 6 | 36 | Leo BARNETT | 13 | Grantham | 1:17.30 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 37 | Lucy WILLATTS | 14 | Grantham | 1:16.07 |
| 2 | 38 | Thomas HILLSON | 12 | Grantham | 1:15.05 |
| 3 | 39 | Amy TAYLOR | 14 | Grantham | 1:14.90 |
| 4 | 40 | Annabelle JAY | 14 | Grantham | 1:13.44 |
| 5 | 41 | Ellena HOWITT | 14 | Grantham | 1:12.50 |
| 6 | 42 | Chloe HOPKINSON | 20 | Grantham | 1:08.40 |
| Heat Number - 8 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 44 | Jack ZERAVICA | 17 | Grantham | 1:05.06 |
| 2 | 46 | Ben CARLYLE | 15 | Grantham | 1:02.17 |
| 3 | 48 | Benjamin ROBERTS | 16 | Grantham | 59.57 |
| 4 | 47 | Zach HOPKINSON | 16 | Grantham | 1:02.03 |
| 5 | 45 | Daniel DEGNAN | 17 | Grantham | 1:03.74 |
| 6 | 43 | Grace TURNER | 18 | Grantham | 1:07.64 |