EVENT 101 Female 800m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 1 | Cassandra Pereira | 14 | Hatfield | 10:03.29 |
| 2 | 3 | Ayla Zolfaghari | 13 | Epping For't | 10:03.10 |
| 3 | 5 | Chloe Cranny | 13 | Epping For't | 10:01.62 |
| 4 | 7 | Eleanor Cox | 16 | Hitchin | 9:57.36 |
| 5 | 6 | Honor Beverstock | 15 | Hatfield | 10:01.08 |
| 6 | 4 | Maia Thompson | 16 | Team Waveney | 10:02.39 |
| 7 | 2 | Isabella Savage | 15 | Potters Bar | 10:03.27 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 9 | Lily Farr | 16 | Bedford SS | 9:55.70 |
| 2 | 11 | Millie Richardson | 18 | Hatfield | 9:51.33 |
| 3 | 13 | Eveline Gaydon | 15 | Chelmsford | 9:43.30 |
| 4 | 15 | Aislin Foley-Wright | 17 | Basildon Ph | 9:41.52 |
| 5 | 14 | Miriam Moukdad | 18 | Bishop Stort | 9:41.64 |
| 6 | 12 | Megan Barnicoat | 13 | Co Peterboro | 9:47.40 |
| 7 | 10 | Lucy Clarke | 14 | Chelmsford | 9:52.26 |
| 8 | 8 | Esmie Kidman | 18 | West Norfolk | 9:56.20 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 17 | Anabelle Kett | 15 | Co Peterboro | 9:38.50 |
| 2 | 19 | Amelia Saunders | 16 | Norwich Swan | 9:36.50 |
| 3 | 21 | Ruby Chapman | 18 | Norwich Swan | 9:33.01 |
| 4 | 23 | Gabriella Troman | 15 | teamipswich | 9:29.79 |
| 5 | 22 | Florence Crowley | 18 | Co St Albans | 9:32.09 |
| 6 | 20 | Francesca Barber | 15 | Co Norwich | 9:35.34 |
| 7 | 18 | Cailin Hehir | 16 | Watford SC | 9:37.68 |
| 8 | 16 | Emma Cushion | 14 | Co Peterboro | 9:39.90 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 25 | Almudena Visser Velez | 22 | Co Cambridge | 9:21.30 |
| 2 | 27 | Amelia Fenner | 14 | Basildon Ph | 9:10.50 |
| 3 | 29 | Jasmine Hall | 14 | Basildon Ph | 9:03.70 |
| 4 | 31 | Cait Cotter | 17 | Chelmsford | 8:46.55 |
| 5 | 30 | Sophie Dowding | 17 | teamipswich | 9:02.50 |
| 6 | 28 | Annie McLeod | 16 | Putteridge | 9:04.73 |
| 7 | 26 | Sadie Hunter | 16 | Co Peterboro | 9:14.62 |
| 8 | 24 | Ever Ives | 15 | Hatfield | 9:23.69 |