| Heat Number - 1 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 3 | 1 | Orlaigh GREER | 11 | S10 | South Lincs Competitive SC | 1:39.99 |
| 4 | 3 | Charlotte BROWNLESS | 12 | Lincoln Trident Swimming Academy | 1:32.92 | |
| 5 | 2 | Lucy JENKINSON | 12 | Deepings SC | 1:34.14 | |
| Heat Number - 2 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 2 | 5 | Georgia MIDDLETON | 12 | Louth Dolphins SC | 1:33.61 | |
| 3 | 7 | Erin ARCHER | 11 | City of Linc Pentaqua SC | 1:26.54 | |
| 4 | 9 | Ellena HOWITT | 11 | Grantham SC | 1:25.58 | |
| 5 | 8 | Lucy WILLATTS | 11 | Grantham SC | 1:23.46 | |
| 6 | 6 | Miley RICHARDSON | 13 | Lincoln Vulcans SC | 1:33.33 | |
| 7 | 4 | Connie MILLNS | 12 | City of Linc Pentaqua SC | 1:35.00 | |
| Heat Number - 3 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 11 | Suzanna BURKE | 11 | Louth Dolphins SC | 1:25.37 | |
| 2 | 13 | Emily TALKES | 12 | Lincoln Vulcans SC | 1:17.72 | |
| 3 | 15 | Mieke MCDONALD | 10 | Deepings SC | DN:C . | |
| 4 | 17 | Lucy DAVIS | 09 | Lincoln Vulcans SC | 1:20.02 | |
| 5 | 16 | Amy PALMER | 11 | City of Linc Pentaqua SC | 1:19.26 | |
| 6 | 14 | Lucy WILSON | 10 | South Lincs Competitive SC | 1:21.56 | |
| 7 | 12 | Maddison HODGIN | 10 | City of Linc Pentaqua SC | 1:19.42 | |
| 8 | 10 | Sophie FOSTER | 11 | Louth Dolphins SC | 1:30.98 | |
| Heat Number - 4 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 19 | Emily BRIGGS | 09 | South Lincs Competitive SC | 1:20.63 | |
| 2 | 21 | Hannah BRUCE | 09 | South Lincs Competitive SC | 1:19.51 | |
| 3 | 23 | Sophie WARD | 09 | Grantham SC | 1:16.78 | |
| 4 | 25 | Rianna ABBOTT | 08 | Grantham SC | 1:16.03 | |
| 5 | 24 | Isabella MIDDLETON | 08 | Louth Dolphins SC | 1:16.32 | |
| 6 | 22 | Maisie MATTHEWS | 11 | Louth Dolphins SC | 1:15.09 | |
| 7 | 20 | Megan LAMB | 09 | Lincoln Vulcans SC | 1:19.75 | |
| 8 | 18 | Megan RUTT | 10 | Boston Amateur SC | 1:20.59 | |
| Heat Number - 5 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 27 | Lucy CARTER | 08 | Louth Dolphins SC | 1:16.47 | |
| 2 | 29 | Jessica HERRIOTT | 08 | South Lincs Competitive SC | 1:18.14 | |
| 3 | 31 | Sigourney BOLTON | 09 | South Lincs Competitive SC | 1:17.35 | |
| 4 | 33 | Elysia SMITH | 10 | Louth Dolphins SC | 1:19.37 | |
| 5 | 32 | Isabella WALTER | 09 | Louth Dolphins SC | 1:14.58 | |
| 6 | 30 | Jessica - Rose DAVISON | 09 | Grantham SC | 1:16.19 | |
| 7 | 28 | Isobel ALLSOP | 10 | Grantham SC | 1:17.07 | |
| 8 | 26 | Lexie HAMILTON | 09 | South Lincs Competitive SC | 1:17.85 | |
| Heat Number - 6 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 35 | Alice-Mae DOWNS | 09 | Lincoln Vulcans SC | 1:15.70 | |
| 2 | 37 | Skye HOLMES | 10 | Louth Dolphins SC | 1:16.65 | |
| 3 | 39 | Charlotte BEMROSE | 08 | Louth Dolphins SC | 1:13.51 | |
| 4 | 41 | Emmy STINTON | 09 | City of Linc Pentaqua SC | 1:15.95 | |
| 5 | 40 | Taliah COUTTS | 08 | City of Linc Pentaqua SC | 1:14.84 | |
| 6 | 38 | Daniela BRINGEMAN | 07 | South Lincs Competitive SC | 1:15.24 | |
| 7 | 36 | Emilia THORNLEY-PAYNE | 08 | Boston Amateur SC | 1:17.13 | |
| 8 | 34 | Eliza BARTON | 05 | Louth Dolphins SC | 1:17.87 | |
| Heat Number - 7 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 43 | Amelie MILLNS | 07 | City of Linc Pentaqua SC | 1:15.88 | |
| 2 | 45 | Sophie COOKSEY | 10 | Louth Dolphins SC | 1:19.54 | |
| 3 | 47 | Olivia SPENCER | 06 | Lincoln Vulcans SC | 1:16.52 | |
| 4 | 49 | Sophie MORSY | 07 | Boston Amateur SC | 1:15.88 | |
| 5 | 48 | Corey FARLEY | 09 | Grantham SC | 1:13.64 | |
| 6 | 46 | Emilie WEBB | 10 | Grantham SC | 1:12.61 | |
| 7 | 44 | Helena FIELD | 09 | Louth Dolphins SC | 1:17.10 | |
| 8 | 42 | Elodie HILES | 08 | Louth Dolphins SC | 1:17.48 | |
| Heat Number - 8 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 53 | Isabelle MCCORKELL | 08 | Gainsborough Dolphins SC | 1:12.09 | |
| 2 | 59 | Holly GILES | 06 | Louth Dolphins SC | 1:09.43 | |
| 3 | 65 | Ruby WARING | 06 | Louth Dolphins SC | 1:09.84 | |
| 4 | 71 | Evie DICKINSON | 08 | Louth Dolphins SC | 1:08.70 | |
| 5 | 68 | Evie TURNER | 06 | Grantham SC | 1:09.66 | |
| 6 | 62 | Charlotte HODGIN | 08 | City of Linc Pentaqua SC | 1:12.39 | |
| 7 | 56 | Casey CLEAVER | 06 | City of Linc Pentaqua SC | 1:13.53 | |
| 8 | 50 | Millie HERRICK | 07 | Deepings SC | DN:C . | |
| Heat Number - 9 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 54 | Katie ROSCOE | 03 | Louth Dolphins SC | 1:12.69 | |
| 2 | 60 | Jessica O'HERLIHY | 06 | South Lincs Competitive SC | 1:11.88 | |
| 3 | 66 | Beatrice FINCH | 06 | South Lincs Competitive SC | 1:10.01 | |
| 4 | 72 | Emma CROKER | 05 | South Lincs Competitive SC | 1:05.48 | |
| 5 | 69 | Alexandra BULAT | 06 | Lincoln Vulcans SC | 1:06.11 | |
| 6 | 63 | Olivia ANSTEY | 08 | Louth Dolphins SC | 1:09.73 | |
| 7 | 57 | Francesca HALLAM-STOTT | 07 | Grantham SC | 1:11.18 | |
| 8 | 51 | Megan BROWN | 09 | Grantham SC | 1:17.79 | |
| Heat Number - 10 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 55 | Grace TWILTON | 08 | Lincoln Vulcans SC | 1:12.12 | |
| 2 | 61 | Mia COPPING | 07 | Lincoln Vulcans SC | 1:10.62 | |
| 3 | 67 | Grace TURNER | 07 | Grantham SC | 1:09.20 | |
| 4 | 73 | Grace MACDONALD | 09 | Grantham SC | 1:04.37 | |
| 5 | 70 | Lilli-Rose CARR | 09 | City of Linc Pentaqua SC | 1:07.08 | |
| 6 | 64 | Alexandra HALLAM-STOTT | 06 | Grantham SC | 1:09.89 | |
| 7 | 58 | Chloe HOPKINSON | 05 | Grantham SC | 1:12.85 | |
| 8 | 52 | Kitty LAMB | 11 | South Lincs Competitive SC | 1:14.29 | |