EVENT 303 Female 12 Yrs/Over 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 1 | Lucy ABBOTT | 12 | Grantham | 6:38.42 |
| 4 | 3 | Amy TAYLOR | 13 | Grantham | 6:16.89 |
| 5 | 2 | Annie WEBSTER | 12 | Grantham | 6:37.34 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 2 | 5 | Grace HOWITT | 15 | Grantham | 6:10.73 |
| 3 | 7 | Ellena HOWITT | 13 | Grantham | 6:04.65 |
| 4 | 9 | Elysia SMITH | 14 | Louth | 6:01.71 |
| 5 | 8 | Ella BLACKBOURN | 16 | Lincoln Vulc | 6:03.90 |
| 6 | 6 | Sophie FOSTER | 13 | Louth | 6:08.02 |
| 7 | 4 | Brooke HEMMINGS | 15 | Lincoln Vulc | 6:12.61 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 11 | Emily BRIGGS | 15 | South Lincs | 5:59.83 |
| 2 | 13 | Suzanna BURKE | 13 | Louth | 5:57.83 |
| 3 | 15 | Charlotte JENKINSON | 14 | Deepings | 5:56.73 |
| 4 | 17 | Sophie WARD | 15 | Grantham | 5:54.65 |
| 5 | 16 | Evie DICKINSON | 16 | Louth | 5:54.84 |
| 6 | 14 | Isabella MIDDLETON | 16 | Louth | 5:56.89 |
| 7 | 12 | Isobel ALLSOP | 14 | Grantham | 5:59.52 |
| 8 | 10 | Harriet MCCORMACK | 15 | Grantham | 6:01.24 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 19 | Jessica - Rose DAVISON | 15 | Grantham | 5:52.75 |
| 2 | 21 | Lucy WILLATTS | 13 | Grantham | 5:51.68 |
| 3 | 23 | Zara DIXON | 16 | Co Lincoln P | 5:48.30 |
| 4 | 26 | Isla GRAY | 14 | Grantham | 5:44.01 |
| 5 | 25 | Erin INGHAM | 16 | Louth | 5:44.89 |
| 6 | 22 | Skye HOLMES | 14 | Louth | 5:48.52 |
| 7 | 20 | Sophie MARSHALL | 19 | Co Lincoln P | 5:52.55 |
| 8 | 18 | Megan LAMB | 15 | Lincoln Vulc | 5:53.24 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 28 | Sophie COOKSEY | 14 | Louth | 5:41.81 |
| 2 | 30 | Liv SPENCER | 18 | Lincoln Vulc | 5:40.93 |
| 3 | 32 | Gracie-May COLE | 16 | Lincoln Vulc | 5:38.51 |
| 4 | 34 | Maisie MATTHEWS | 13 | Louth | 5:35.45 |
| 5 | 33 | Emily TALKES | 12 | Lincoln Vulc | 5:36.55 |
| 6 | 31 | Jessica HERRIOTT | 16 | South Lincs | 5:40.08 |
| 7 | 29 | Daniela BRINGEMAN | 17 | South Lincs | 5:41.10 |
| 8 | 27 | Lexie HAMILTON | 15 | South Lincs | 5:41.81 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 37 | Lillie HAMILTON | 16 | South Lincs | 5:26.73 |
| 2 | 39 | Grace TURNER | 17 | Grantham | 5:14.60 |
| 3 | 41 | Francesca HALLAM-STOTT | 17 | Grantham | 5:10.82 |
| 4 | 43 | Beatrice FINCH | 18 | South Lincs | 5:08.10 |
| 5 | 42 | Grace MACDONALD | 15 | Grantham | 5:08.98 |
| 6 | 40 | Olivia ANSTEY | 16 | Louth | 5:11.02 |
| 7 | 38 | Hannah BRUCE | 15 | South Lincs | 5:15.32 |
| 8 | 36 | Megan BROWN | 15 | Grantham | 5:27.74 |