EVENT 301 Boy/Girl 12 Yrs/Under 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 1 | Livia STACEY | 10 | Co Leeds | 7:35.80 |
| 1 | 3 | Emily YANG | 11 | Co Manch Aq | 7:18.68 |
| 2 | 5 | Owen TEMPEST | 10 | Co Leeds | 7:10.20 |
| 3 | 7 | Hogan LAM | 10 | Co Leeds | 7:07.10 |
| 4 | 9 | Amelia MATSON | 10 | Co Leeds | 7:02.20 |
| 5 | 8 | Lily VEEVERS | 11 | Co Leeds | 7:05.40 |
| 6 | 6 | Mia THOMSON | 10 | Co Leeds | 7:10.00 |
| 7 | 4 | Amelie COTTERILL | 10 | Co Leeds | 7:11.10 |
| 8 | 2 | Alfie CRAGGS | 11 | Co Leeds | 7:30.00 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 11 | Emily ROWE | 11 | Co Manch Aq | 6:55.65 |
| 1 | 13 | Dominic POKAM | 12 | Co Manch Aq | 6:52.46 |
| 2 | 14 | Sebastian HUNTER | 12 | Co Leeds | 6:50.30 |
| 3 | 16 | Reggie SPENCE | 12 | Co Leeds | 6:45.00 |
| 4 | 18 | Noah DARNELL | 11 | Co Leeds | 6:37.80 |
| 5 | 17 | Ella COLEMAN | 11 | Co Leeds | 6:43.10 |
| 6 | 15 | Callum FOZARD | 11 | Co Leeds | 6:45.00 |
| 7 | 39 | Theo SWAN | 12 | Rotherham Mo | 6:51.00 |
| 8 | 12 | Freya ELLIS | 10 | Co Leeds | 6:53.90 |
| 9 | 10 | Penelope DALLIMORE | 11 | Co Leeds | 7:01.10 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 20 | Amy CHOULARTON | 11 | Co Manch Aq | 6:34.93 |
| 1 | 22 | Amit MALTZ | 12 | Co Leeds | 6:21.70 |
| 2 | 24 | Patrick O'HARA | 12 | Co Leeds | 6:16.00 |
| 3 | 26 | Connor MCCULLEN | 12 | Co Leeds | 6:08.50 |
| 4 | 28 | Florence DIXON | 11 | Co Leeds | 6:05.50 |
| 5 | 27 | M AZANA-BALL | 11 | Co Leeds | 6:05.80 |
| 6 | 25 | Sophia YU | 12 | Co Manch Aq | 6:10.61 |
| 7 | 23 | Isabelle HALL | 11 | Co Leeds | 6:19.00 |
| 8 | 21 | Holly HARRISON | 12 | Co Leeds | 6:25.50 |
| 9 | 19 | Ava BRADLEY | 12 | Co Leeds | 6:35.90 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 30 | James THOMSON | 12 | Co Leeds | 6:02.70 |
| 1 | 32 | Oliver BARRETT | 11 | Co Leeds | 5:59.00 |
| 2 | 34 | William DALE-WOOD | 12 | Thirsk WH | 5:55.00 |
| 3 | 36 | Poppy NUTTMAN | 12 | Spenborough | 5:47.53 |
| 4 | 38 | Matei STOICESCU | 12 | Co Leeds | 5:41.20 |
| 5 | 37 | Jessica WOODS | 12 | Spenborough | 5:46.60 |
| 6 | 35 | Hayden LAM | 12 | Co Leeds | 5:52.60 |
| 7 | 33 | Molly NORTON | 12 | Co Leeds | 5:55.00 |
| 8 | 31 | Shae BRYANT | 11 | Co Leeds | 6:00.30 |
| 9 | 29 | Jackson CLARKE | 12 | Co Leeds | 6:05.00 |