EVENT 301 Mixed 12 Yrs/Under 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 1 | Keaton-James HALL | 12 | Bo Barnsley | 7:45.68 |
| 2 | 3 | Oskar SZAMUK | 11 | Co Leeds | 7:29.90 |
| 3 | 5 | Erin HARGREAVES | 12 | Co Leeds | 7:10.00 |
| 4 | 7 | Henry ROLLINGS | 11 | Co Leeds | 7:09.00 |
| 5 | 6 | Daisy RASOOL | 10 | Co Leeds | 7:10.00 |
| 6 | 4 | Anneliese CIRSTEA | 10 | Co Leeds | 7:15.00 |
| 7 | 2 | Ryker BOYD | 11 | Co Leeds | 7:30.00 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 9 | Jessica SUTCLIFFE | 9 | Co Leeds | 7:00.00 |
| 2 | 11 | Alfie CALAM | 9 | Co Leeds | 7:00.00 |
| 3 | 13 | Isabelle JORDAN | 10 | Co Leeds | 7:00.00 |
| 4 | 15 | Lily HOGAN | 10 | Co Leeds | 6:57.50 |
| 5 | 14 | Jude CALVERT | 12 | Co Leeds | 7:00.00 |
| 6 | 12 | Charlie MACFADYEN | 11 | Co Leeds | 7:00.00 |
| 7 | 10 | Hannah HEPBURN-WOOD | 10 | Co Leeds | 7:00.00 |
| 8 | 8 | Gracie HART | 10 | Co Leeds | 7:00.00 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 17 | Isabella HUTCHISON | 10 | Co Leeds | 6:46.10 |
| 2 | 19 | Madeleine FLAHERTY | 11 | Co Leeds | 6:32.40 |
| 3 | 21 | George BEILBY-WOODWARD | 11 | Co Leeds | 6:30.00 |
| 4 | 23 | Ayla CARRY | 11 | Co Leeds | 6:23.80 |
| 5 | 22 | Robyn CROSS | 12 | Lincoln Vulc | 6:30.00 |
| 6 | 20 | Ruby TALKES | 9 | Lincoln Vulc | 6:30.00 |
| 7 | 18 | Martha NEWMAN | 10 | Co Leeds | 6:37.40 |
| 8 | 16 | Sophia Xiu Hui KOK | 11 | Co Leeds | 6:50.50 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 25 | Isabelle LOK | 11 | Co Leeds | 6:21.60 |
| 2 | 27 | Callum YOUNG | 10 | Co Leeds | 6:20.90 |
| 3 | 29 | Adam MOHAMED | 10 | Co Leeds | 6:19.00 |
| 4 | 31 | Yin Ho Adrian CHAN | 11 | Co Leeds | 6:12.80 |
| 5 | 30 | Olive MITCHELL | 11 | Co Leeds | 6:15.47 |
| 6 | 28 | David MCINTOSH | 9 | Co Leeds | 6:20.80 |
| 7 | 26 | Emilia DEVERILL | 12 | Co Leeds | 6:21.00 |
| 8 | 24 | Francesca SPALDING | 11 | Co Leeds | 6:22.50 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 33 | Qian SHEN | 11 | Co Leeds | 6:08.50 |
| 2 | 35 | Evie MORAN | 12 | Co Leeds | 5:59.50 |
| 3 | 37 | Tyler GREEN | 11 | Co Leeds | 5:58.20 |
| 4 | 38 | Isabelle PARK | 11 | Co Leeds | 5:55.40 |
| 5 | 47 | Harry DIXON | 12 | Co Leeds | 5:55.90 |
| 6 | 36 | Bobby WALLIS | 12 | Lincoln Vulc | 5:58.88 |
| 7 | 34 | Lewis LUNG | 12 | Co Leeds | 6:00.60 |
| 8 | 32 | Isla CUNDILL | 12 | Co Leeds | 6:10.20 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 40 | Evelyn ATKINSON | 11 | Co Leeds | 5:52.00 |
| 2 | 42 | Ava MCLARKEY | 11 | Co Leeds | 5:46.40 |
| 3 | 44 | Barney HOBBS | 12 | Co Leeds | 5:44.10 |
| 4 | 46 | Jessica COLLEY | 12 | Co Leeds | 5:30.40 |
| 5 | 45 | Madeline BECKRAM | 12 | Co Leeds | 5:37.60 |
| 6 | 43 | Oliver BARKER | 12 | Co Leeds | 5:46.40 |
| 7 | 41 | Liam LI | 11 | Co Leeds | 5:49.30 |
| 8 | 39 | Betsy KIRKLEY | 12 | Co Leeds | 5:52.60 |