EVENT 36 Female 100m Backstroke - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 3 | 1 | Tabitha LAMBERT | 10 | Lincoln Vulc | 2:03.00 |
| 4 | 2 | Jemima-Blu BRENNAN | 9 | Gainsborough | 2:00.00 |
| 5 | 3 | Honey FLOWER | 11 | Grantham | 1:53.79 |
| 6 | 4 | Matilda HARPER | 10 | Grantham | 1:53.50 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 5 | Isabelle TEASDALE | 9 | Louth | 1:53.40 |
| 2 | 6 | Annabelle SEAGROATT | 10 | Louth | 1:53.00 |
| 3 | 7 | Rian TEMPEST | 10 | Skegness | 1:50.00 |
| 4 | 8 | Nancy FRENCH | 10 | Louth | 1:50.00 |
| 5 | 9 | Jessica REEVES | 12 | Lincoln Vulc | 1:49.10 |
| 6 | 10 | Bethany MEAKIN | 11 | Grantham | 1:45.80 |
| 7 | 11 | Edith TEMPLEMAN | 9 | Louth | 1:45.43 |
| 8 | 12 | Evie BURGESS | 11 | Lincoln Vulc | 1:45.00 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 13 | Elizabeth MAINWARING | 12 | Boston | 1:44.99 |
| 2 | 14 | Isla GARNETT | 11 | Lincoln Vulc | 1:43.79 |
| 3 | 15 | Elizabeth GARLICK | 10 | Louth | 1:41.69 |
| 4 | 16 | Ophelia GOODALE | 11 | Deepings | 1:41.23 |
| 5 | 17 | Sophie HARRISON | 15 | Deepings | 1:40.08 |
| 6 | 18 | Erin MELLER | 12 | Louth | 1:38.28 |
| 7 | 19 | Betsy BOLAND | 13 | Louth | 1:37.30 |
| 8 | 20 | Amaya MONTEALEGRE | 12 | Lincoln Vulc | 1:36.08 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 21 | Olivia CHARITY | 14 | Grantham | 1:35.85 |
| 2 | 22 | Abigail TAYLOR | 12 | Grantham | 1:33.53 |
| 3 | 23 | Florence SHEPHERD | 14 | Gainsborough | 1:33.43 |
| 4 | 24 | Florence MCCLURE | 10 | Lincoln TSA | 1:33.41 |
| 5 | 25 | C TOH-GRUDZINSKI | 9 | Lincoln Vulc | 1:30.71 |
| 6 | 26 | Florence HARPER | 13 | Grantham | 1:29.58 |
| 7 | 27 | Maisie DARBY | 15 | Lincoln Vulc | 1:29.56 |
| 8 | 28 | Isabelle CLAYTON | 13 | Grantham | 1:28.69 |
| Heat Number - 5 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 29 | Amy BARKER | 12 | Lincoln Vulc | 1:28.10 |
| 2 | 30 | Hollie-Ann CROOK | 11 | Grantham | 1:28.02 |
| 3 | 31 | Francesca WESTON | 11 | Grantham | 1:27.50 |
| 4 | 32 | Madeline SURTEES | 13 | Grantham | 1:25.70 |
| 5 | 33 | Ella-Rose HUNTER | 13 | Lincoln Vulc | 1:25.20 |
| 6 | 34 | Izabella ZANIEWSKA | 13 | Boston | 1:24.37 |
| 7 | 35 | Poppy CHAPMAN | 14 | Louth | 1:23.96 |
| 8 | 37 | Isla SCOTT | 15 | Lincoln Vulc | 1:22.20 |
| Heat Number - 6 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 38 | Chloe APPLEWHITE | 10 | Gainsborough | 1:22.10 |
| 2 | 39 | Caitlin CROSS | 13 | Lincoln Vulc | 1:22.01 |
| 3 | 40 | Ella HE | 13 | Gainsborough | 1:20.78 |
| 4 | 41 | Grace HOWITT | 17 | Grantham | 1:20.17 |
| 5 | 42 | Gracie DAWSON | 12 | Deepings | 1:19.80 |
| 6 | 43 | Emma PEPPER | 14 | Deepings | 1:17.95 |
| 7 | 44 | Madeleine SEAGROATT | 13 | Louth | 1:17.24 |
| 8 | 45 | Charlotte TURNER | 15 | Lincoln Vulc | 1:16.67 |
| Heat Number - 7 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 47 | Arabella PEARCE | 13 | Louth | 1:13.88 |
| 2 | 49 | Isobel VAUSE | 17 | Deepings | 1:12.99 |
| 3 | 51 | Olivia KING | 14 | Deepings | 1:11.98 |
| 4 | 53 | Maisie MATTHEWS | 15 | Louth | 1:08.43 |
| 5 | 52 | Ellena HOWITT | 14 | Grantham | 1:11.88 |
| 6 | 50 | Isla LORMOR | 13 | Gainsborough | 1:12.26 |
| 7 | 48 | Lizzy LERESCHE HANDS | 14 | Grantham | 1:13.34 |
| 8 | 46 | Evie DAVIES | 13 | Deepings | 1:14.42 |