EVENT 215 Female 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 2 | 2 | Florence Richbell | 12 | S12 | Flitwick | 6:16.50 |
| 3 | 4 | Megan Randall | 15 | | Royston | 4:49.71 |
| 4 | 6 | Elizabeth Gore | 15 | | Epping For't | 4:47.90 |
| 5 | 5 | Freya Hill | 15 | | New Hall | 4:48.00 |
| 6 | 3 | Ida Corcoran | 17 | S9 | Flitwick | 5:57.21 |
| 7 | 1 | Charlotte Ryan | 26 | S6 | Runnymede | 8:45.70 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 8 | Daisy Jubb | 16 | | Co St Albans | 4:45.31 |
| 2 | 10 | Yasmine Ollerenshaw | 17 | | Flitwick | 4:44.76 |
| 3 | 12 | Ayla Zolfaghari | 15 | | Epping For't | 4:44.50 |
| 4 | 14 | Bethany Crawley | 18 | | teamipswich | 4:44.25 |
| 5 | 13 | Anastasja Wall | 16 | | Co Norwich | 4:44.30 |
| 6 | 11 | Ava Turner | 17 | | Basildon Ph | 4:44.62 |
| 7 | 9 | Connie Flitton | 15 | | Dunstable | 4:45.10 |
| 8 | 7 | Lola-Rose Curtin | 15 | | Halesworth | 4:47.45 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 16 | Antonia Elias | 17 | | Watford SC | 4:42.99 |
| 2 | 18 | Ava Black | 19 | | Co St Albans | 4:42.71 |
| 3 | 20 | Emma Cushion | 16 | | Co Peterboro | 4:42.07 |
| 4 | 22 | Orlagh Quarrell | 16 | | Watford SC | 4:40.36 |
| 5 | 21 | Isabel Thomas | 18 | | Newmarket | 4:40.50 |
| 6 | 19 | Erin Woodrow | 19 | | West Norfolk | 4:42.46 |
| 7 | 17 | Lyla Flello | 17 | | Co Norwich | 4:42.87 |
| 8 | 15 | Freya May | 16 | | Team Waveney | 4:44.09 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 24 | Summer Evason | 17 | | Watford SC | 4:39.31 |
| 2 | 26 | Chloe Cranny | 15 | | Epping For't | 4:37.40 |
| 3 | 28 | Chloe Butler | 22 | | Norwich Swan | 4:36.94 |
| 4 | 30 | Lois Smith | 16 | | Basildon Ph | 4:35.65 |
| 5 | 29 | Heidi King | 15 | | Hemel Hemp | 4:35.79 |
| 6 | 27 | Freya Cox | 15 | | Norwich Swan | 4:37.32 |
| 7 | 25 | Edie Foster | 15 | | Bishop Stort | 4:37.60 |
| 8 | 23 | Isabella Da Silva | 15 | | Basildon Ph | 4:40.34 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 32 | Lily Steel | 16 | | teamipswich | 4:34.87 |
| 2 | 34 | Ruby Chapman | 20 | | Norwich Swan | 4:33.97 |
| 3 | 36 | E Barth-Wehrenalp | 16 | | Chelmsford | 4:33.40 |
| 4 | 38 | Nina Allen | 15 | | Newmarket | 4:32.96 |
| 5 | 37 | Jorja Atkinson | 15 | | Co Cambridge | 4:33.10 |
| 6 | 35 | Valentina Tinnirello | 16 | | Potters Bar | 4:33.64 |
| 7 | 33 | Francesca Barber | 17 | | Co Norwich | 4:34.24 |
| 8 | 31 | Olivia Croft | 15 | | Cheshunt | 4:35.08 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Cat | Club | Time |
| 1 | 40 | Erin Uttridge | 17 | | teamipswich | 4:31.51 |
| 2 | 42 | Sadie Hunter | 18 | | Co Peterboro | 4:28.40 |
| 3 | 44 | Amelia Porzio | 18 | | Putteridge | 4:27.80 |
| 4 | 46 | Jasmine Hall | 16 | | Basildon Ph | 4:15.80 |
| 5 | 45 | Amelia Fenner | 16 | | Basildon Ph | 4:20.86 |
| 6 | 43 | Annie McLeod | 18 | | Putteridge | 4:27.82 |
| 7 | 41 | Anabelle Kett | 17 | | Co Peterboro | 4:29.50 |
| 8 | 39 | Amelia Saunders | 18 | | Norwich Swan | 4:32.10 |