EVENT 303 Female 100m Backstroke - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | YoB | Club | Time |
| 2 | 1 | Matilda NEWPORT | 13 | Weymouth | 2:15.50 |
| 3 | 3 | Shanice WOOD | 16 | Seagulls SC | 2:03.98 |
| 4 | 2 | Cleo-Mae COBB | 16 | Seagulls SC | 2:04.18 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | YoB | Club | Time |
| 1 | 4 | Bethan MOFFAT | 15 | Seagulls SC | 2:02.65 |
| 2 | 6 | Georgia BAILEY | 15 | West Dorset | 1:57.99 |
| 3 | 8 | Iona COOK | 14 | Bridport Bar | 1:52.34 |
| 4 | 7 | Annabelle PROWSE | 13 | West Dorset | 1:53.52 |
| 5 | 5 | Emilia BLAKE-EVERDEN | 14 | Weymouth | 2:00.71 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | YoB | Club | Time |
| 1 | 10 | Poppy GOUGH | 14 | West Dorset | 1:45.45 |
| 2 | 12 | Phoebe TIPPLE-EVANS | 14 | Wareham | 1:43.66 |
| 3 | 14 | Ella JENKINSON | 13 | Blandford | 1:41.93 |
| 4 | 13 | Olivia EURIPIDES | 15 | Wareham | 1:42.98 |
| 5 | 11 | Isla SEVENOAKS | 14 | Blandford | 1:44.11 |
| 6 | 9 | Olivia JORDAN | 11 | Weymouth | 1:49.94 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | YoB | Club | Time |
| 1 | 16 | Chloe EDEN | 15 | Poole | 1:39.14 |
| 2 | 18 | Evie STEBBING | 15 | Poole | 1:38.19 |
| 3 | 20 | Orla HAYTER | 15 | Poole | 1:37.04 |
| 4 | 19 | Caitlin MCGRATH | 11 | Poole | 1:37.48 |
| 5 | 17 | Nell GALLIVER-WILLIAMS | 14 | Bridport Bar | 1:38.88 |
| 6 | 15 | Neve COLLINSON | 13 | Wareham | 1:41.76 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | YoB | Club | Time |
| 1 | 22 | Darcy ALLEN | 14 | Poole | 1:35.09 |
| 2 | 24 | Amare FERREIRA | 14 | Poole | 1:31.74 |
| 3 | 26 | Martha JAMES | 12 | West Dorset | 1:31.20 |
| 4 | 25 | Sasha WOOD | 15 | Seagulls SC | 1:31.67 |
| 5 | 23 | Emily COLLINS | 15 | Poole | 1:34.39 |
| 6 | 21 | Poppy BOYES | 14 | West Dorset | 1:36.09 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | YoB | Club | Time |
| 1 | 28 | Daisy SLATER | 13 | Wareham | 1:29.13 |
| 2 | 30 | Katrina SCHMIDT | 11 | West Dorset | 1:27.65 |
| 3 | 32 | Sophie HUGGINS | 11 | Poole | 1:25.33 |
| 4 | 31 | Elizabeth YOUNG | 12 | N Dorset SC | 1:25.79 |
| 5 | 29 | Erin REDFERN | 11 | Seagulls SC | 1:28.25 |
| 6 | 27 | Jessica BENNETT | 13 | Poole | 1:30.88 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | YoB | Club | Time |
| 1 | 34 | Amelia FANCINI | 09 | S Bournem'th | 1:24.43 |
| 2 | 36 | Aadya SINGH | 10 | S Bournem'th | 1:22.04 |
| 3 | 38 | Katherine CHAPLEO | 07 | Poole | 1:19.76 |
| 4 | 37 | Evie WILLIAMS | 12 | S Bournem'th | 1:20.25 |
| 5 | 35 | Ava-Mae MATTOCKS | 09 | N Dorset SC | 1:22.79 |
| 6 | 33 | Annabella EURIPIDES | 11 | Wareham | 1:24.47 |
| Heat Number - 8 |
| Lane | Comp.No. | Name | YoB | Club | Time |
| 1 | 40 | Chloe TSE | 10 | Seagulls SC | 1:18.31 |
| 2 | 42 | Amelia SCOTT | 10 | S Bournem'th | 1:15.55 |
| 3 | 44 | Talei RAWAMILA | 10 | West Dorset | 1:13.27 |
| 4 | 43 | Mia PALMER | 11 | Poole | 1:14.43 |
| 5 | 41 | Siena GADD | 11 | Seagulls SC | 1:18.16 |
| 6 | 39 | Freya ESCOTT | 08 | Poole | 1:18.56 |