EVENT 511 Women 400m Freestyle - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 1 | Lucia Lopez | 15 | Co Milton K | 4:31.14 |
| 1 | 3 | Emilia Oliver | 14 | RTW Monson | 4:30.48 |
| 2 | 5 | Lily Freeman | 15 | Northampton | 4:29.60 |
| 3 | 7 | Ines Guimond-Beetham | 14 | Camden Swiss | 4:29.31 |
| 4 | 9 | Evie Clare | 13 | Stockport Mo | 4:28.90 |
| 5 | 8 | Amber Downham | 17 | Plymouth Lea | 4:28.93 |
| 6 | 6 | Ella Homan | 15 | Co Birm'ham | 4:29.56 |
| 7 | 4 | Jessica Smelt | 15 | Bo Kirklees | 4:30.17 |
| 8 | 2 | Maisie Dickinson | 15 | Wycombe Dist | 4:30.95 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 11 | Skye Austin-Burrows | 15 | Rushmoor Ryl | 4:28.67 |
| 1 | 13 | Alexandra Bulat | 16 | Lincoln Vulc | 4:28.55 |
| 2 | 15 | Lola Burns | 16 | Beckenham | 4:28.22 |
| 3 | 17 | Daisy Purchase | 16 | Rotherham Mo | 4:27.87 |
| 4 | 19 | Hannah Hodgkiss | 16 | Repton | 4:27.83 |
| 5 | 18 | Emily McWilliam | 17 | Seagulls SC | 4:27.84 |
| 6 | 16 | Eliza Pinkstone | 17 | Stockport Mo | 4:28.06 |
| 7 | 14 | Kerry Hennie | 14 | Warrington W | 4:28.53 |
| 8 | 12 | Izzy Blackhurst | 15 | TauntonDeane | 4:28.62 |
| 9 | 10 | Maisie Brown | 14 | Rushmoor Ryl | 4:28.82 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 21 | Elysia Stephens | 13 | Co Birm'ham | 4:27.10 |
| 1 | 23 | Zara Beaumont | 16 | Worcester | 4:26.99 |
| 2 | 25 | Charlotte Surrell | 15 | Chase | 4:26.55 |
| 3 | 27 | Cait Cotter | 15 | Chelmsford | 4:26.36 |
| 4 | 29 | Evangeline Belt | 16 | Plymouth Lea | 4:25.94 |
| 5 | 28 | Lucy Parsons | 15 | Co Liverpool | 4:26.24 |
| 6 | 26 | Holly Lamb | 17 | Co Leicester | 4:26.40 |
| 7 | 24 | Sholah Robinson | 16 | Co Sheffield | 4:26.90 |
| 8 | 22 | Eleanor Broughton | 16 | Repton | 4:27.04 |
| 9 | 20 | Madison Rens | 15 | Co Liverpool | 4:27.47 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 31 | Abby Mitchell | 16 | Co Leicester | 4:25.76 |
| 1 | 33 | Sophie Davies | 15 | Millfield | 4:25.66 |
| 2 | 35 | Alicia Massie | 17 | Repton | 4:25.02 |
| 3 | 37 | Eve Doherty | 14 | Co Sheffield | 4:24.84 |
| 4 | 39 | Mia Burslem | 16 | Co Liverpool | 4:24.44 |
| 5 | 38 | Charlotte Roome | 15 | Derventio | 4:24.48 |
| 6 | 36 | Chloe Goodridge | 17 | Northampton | 4:25.02 |
| 7 | 34 | Gemma Dilks | 17 | Tiverton | 4:25.15 |
| 8 | 32 | Annabel Pilgrim | 16 | Mt Kelly | 4:25.70 |
| 9 | 30 | Madison Emment | 15 | Guildford Ct | 4:25.90 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 41 | Emily Johnson | 16 | Severnside | 4:23.83 |
| 1 | 43 | Louise Ashford | 17 | Maidenhead | 4:23.70 |
| 2 | 45 | Rosie Richards | 16 | Rushmoor Ryl | 4:23.32 |
| 3 | 47 | Ruby Wheeler | 16 | Basildon Ph | 4:23.05 |
| 4 | 49 | Alice Young | 14 | Guildford Ct | 4:23.01 |
| 5 | 48 | Harriet Oxley | 17 | Repton | 4:23.03 |
| 6 | 46 | Louise Bressler | 16 | Guildford Ct | 4:23.19 |
| 7 | 44 | Georgia Robertson | 17 | Co Sheffield | 4:23.65 |
| 8 | 42 | Molly Baker | 15 | Co Sheffield | 4:23.74 |
| 9 | 40 | Eve Tinsley | 16 | Newcastle St | 4:23.90 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 52 | Hollie Wilson | 14 | Co Leeds | 4:22.53 |
| 1 | 56 | Ruby Griffiths | 16 | Mt Kelly | 4:20.64 |
| 2 | 60 | Henrietta D'Ammassa | 17 | Repton | 4:19.47 |
| 3 | 64 | Lara Thomson | 17 | Co Leeds | 4:15.59 |
| 4 | 68 | Beatrice Varley | 19 | Plymouth Lea | 4:11.34 |
| 5 | 66 | Lucy Fox | 16 | Wycombe Dist | 4:12.59 |
| 6 | 62 | Leah Schlosshan | 17 | Co Leeds | 4:18.14 |
| 7 | 58 | Pearle Griffiths | 19 | SurreyUni SC | 4:19.93 |
| 8 | 54 | Emma Price | 14 | Sedgefield | 4:21.64 |
| 9 | 50 | Emily Forwood | 18 | Mt Kelly | 4:22.90 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 0 | 53 | Eleanor Kay | 16 | Bolton Metro | 4:22.16 |
| 1 | 57 | Amelia Brian | 17 | Beckenham | 4:20.06 |
| 2 | 61 | Amelie Blocksidge | 13 | Co Salford | 4:18.75 |
| 3 | 65 | Evie Dilley | 16 | Millfield | 4:15.38 |
| 4 | 69 | Freya Colbert | 18 | Loughborogh | 4:02.71 |
| 5 | 67 | Aimee Hood | 18 | Co Birm'ham | 4:11.46 |
| 6 | 63 | Merissa Booth | 17 | Wycombe Dist | 4:15.84 |
| 7 | 59 | Ava Cook | 14 | Co Sheffield | 4:19.86 |
| 8 | 55 | Anna Farrow | 17 | Co Leicester | 4:21.34 |
| 9 | 51 | Mollie Fisher | 17 | Rotherham Mo | 4:22.59 |