EVENT 601 Girls 12 Yrs/Over 800m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 3 | 1 | Niamh O'Meara | 12 | Watford SC | 11:21.63 |
| 4 | 3 | Imola Jozsa | 12 | Hatfield | 11:12.58 |
| 5 | 2 | Heather Mann | 12 | Stevenage | 11:16.94 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 5 | Molly Cobbold | 12 | Hoddesdon | 10:52.44 |
| 2 | 7 | Isabel Murtagh | 12 | Hatfield | 10:45.02 |
| 3 | 9 | Isabella Yeabsley | 12 | Hatfield | 10:41.91 |
| 4 | 11 | Antonia Jubb | 13 | Hatfield | 10:34.20 |
| 5 | 10 | Gemma Nottage | 13 | Watford SC | 10:34.43 |
| 6 | 8 | Bella Parkus | 13 | Hoddesdon | 10:43.09 |
| 7 | 6 | Sofia Peccei | 13 | Watford SC | 10:49.80 |
| 8 | 4 | Grace Cawley | 12 | Hemel Hemp | 10:54.13 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 13 | Georgia Pritchard | 13 | Hatfield | 10:28.12 |
| 2 | 15 | Kiera Beaver | 14 | Watford SC | 10:23.67 |
| 3 | 17 | Larissa Dean | 16 | Harpenden | 10:18.07 |
| 4 | 19 | Brianna Mazey | 17 | Tring | 10:15.63 |
| 5 | 18 | Francesca Peccei | 15 | Watford SC | 10:16.77 |
| 6 | 16 | Eleanor Craig | 14 | Watford SC | 10:23.56 |
| 7 | 14 | Jessie Bird | 15 | Stevenage | 10:25.81 |
| 8 | 12 | Dayna Shepperson | 13 | Potters Bar | 10:32.65 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 21 | Alice Richardson | 15 | Harpenden | 10:14.31 |
| 2 | 23 | Gemma Hanson | 15 | Hatfield | 10:09.20 |
| 3 | 25 | Ela Norton | 14 | Hatfield | 9:59.85 |
| 4 | 27 | Valeria Giron | 13 | Hatfield | 9:56.09 |
| 5 | 26 | Jessica Heesom | 15 | Potters Bar | 9:57.46 |
| 6 | 24 | Ellie Holliss | 14 | Co St Albans | 10:02.78 |
| 7 | 22 | Amelie Brown | 16 | Watford SC | 10:13.91 |
| 8 | 20 | Agnes Burns | 17 | Harpenden | 10:15.39 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 29 | Isobel Georgiou | 16 | Hatfield | 9:55.67 |
| 2 | 31 | Lily Merrett | 15 | Hoddesdon | 9:35.30 |
| 3 | 33 | Georgia Purkis | 16 | Hemel Hemp | 9:33.41 |
| 4 | 35 | Alice Fender | 17 | Hemel Hemp | 9:20.23 |
| 5 | 34 | Erin O'Meara | 15 | Watford SC | 9:25.81 |
| 6 | 32 | Tegan Wollaston | 19 | Cheshunt | 9:34.10 |
| 7 | 30 | Jessica Keogh | 14 | Hatfield | 9:39.05 |
| 8 | 28 | Lucy King | 15 | Hitchin | 9:55.72 |