EVENT 501 Girls 10 Yrs/Over 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 3 | 1 | Raissa Vickery | 11 | Co St Albans | 6:01.50 |
| 4 | 3 | Carys Toland | 12 | Co St Albans | 5:40.65 |
| 5 | 2 | Amy Harper | 11 | Watford SC | 6:00.18 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 2 | 5 | Charlotte Williams | 12 | Cheshunt | 5:38.75 |
| 3 | 7 | Niamh O'Meara | 12 | Watford SC | 5:32.59 |
| 4 | 9 | Grace Cawley | 12 | Hemel Hemp | 5:16.59 |
| 5 | 8 | Imola Jozsa | 12 | Hatfield | 5:30.99 |
| 6 | 6 | Heather Mann | 12 | Stevenage | 5:34.38 |
| 7 | 4 | Megan Worley | 12 | Watford SC | 5:39.31 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 11 | Bella Parkus | 13 | Hoddesdon | 5:13.79 |
| 2 | 13 | Dayna Shepperson | 13 | Potters Bar | 5:10.90 |
| 3 | 15 | Georgia Pritchard | 13 | Hatfield | 5:07.61 |
| 4 | 17 | Isabella Yeabsley | 12 | Hatfield | 5:04.77 |
| 5 | 16 | Kiera Beaver | 14 | Watford SC | 5:05.62 |
| 6 | 14 | Antonia Jubb | 13 | Hatfield | 5:09.07 |
| 7 | 12 | Molly Cobbold | 12 | Hoddesdon | 5:11.04 |
| 8 | 10 | Kaia Phillips | 12 | Bishop Stort | 5:15.60 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 19 | Abi Larkman | 14 | Hoddesdon | 5:03.10 |
| 2 | 21 | Lucy Coia-Bell | 13 | Co St Albans | 5:01.11 |
| 3 | 23 | Emilia Dunwoodie | 13 | Co St Albans | 4:59.86 |
| 4 | 25 | Ela Norton | 14 | Hatfield | 4:56.05 |
| 5 | 24 | Ellie Holliss | 14 | Co St Albans | 4:57.44 |
| 6 | 22 | Eleanor Craig | 14 | Watford SC | 5:01.08 |
| 7 | 20 | Isabel Murtagh | 12 | Hatfield | 5:01.24 |
| 8 | 18 | Gemma Nottage | 13 | Watford SC | 5:03.50 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 27 | Daisy Sandon | 15 | Stevenage | 4:54.18 |
| 2 | 29 | Agnes Burns | 17 | Harpenden | 4:52.96 |
| 3 | 31 | Jessica Turley | 16 | Hitchin | 4:51.94 |
| 4 | 33 | Millie Fields | 14 | Bishop Stort | 4:50.30 |
| 5 | 32 | Lucy King | 15 | Hitchin | 4:51.48 |
| 6 | 30 | Lucy Park | 22 | Watford SC | 4:52.00 |
| 7 | 28 | Anastasia Wilkinson | 13 | Hatfield | 4:53.67 |
| 8 | 26 | Francesca Peccei | 15 | Watford SC | 4:54.42 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 35 | Isobel Georgiou | 16 | Hatfield | 4:47.85 |
| 2 | 37 | Natasha Bentley | 16 | Hatfield | 4:45.60 |
| 3 | 39 | Gemma Hanson | 15 | Hatfield | 4:43.95 |
| 4 | 41 | Tegan Wollaston | 19 | Cheshunt | 4:42.60 |
| 5 | 40 | Jessica Keogh | 14 | Hatfield | 4:43.81 |
| 6 | 38 | Valeria Giron | 13 | Hatfield | 4:44.85 |
| 7 | 36 | Sarah Carroll | 16 | Bishop Stort | 4:47.21 |
| 8 | 34 | Emily Lush | 16 | Potters Bar | 4:49.52 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club/Country | Time |
| 1 | 43 | Lauren Stott | 16 | Hatfield | 4:41.84 |
| 2 | 45 | Georgia Purkis | 16 | Hemel Hemp | 4:40.02 |
| 3 | 47 | Lily Merrett | 15 | Hoddesdon | 4:32.08 |
| 4 | 49 | Alice Fender | 17 | Hemel Hemp | 4:29.72 |
| 5 | 48 | Billie Grant | 16 | Hatfield | 4:31.62 |
| 6 | 46 | Erin O'Meara | 15 | Watford SC | 4:35.20 |
| 7 | 44 | Jessica Heesom | 15 | Potters Bar | 4:41.18 |
| 8 | 42 | Sophie Quach | 20 | Hatfield | 4:41.86 |