| Heat Number - 1 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 3 | 1 | Orlaigh GREER | 11 | SB10 | South Lincs Competitive SC | 1:03.89 |
| 4 | 3 | Ava CUTTS | 12 | City of Linc Pentaqua SC | 52.66 | |
| 5 | 2 | Isabelle PARKES | 13 | Gainsborough Dolphins SC | 53.10 | |
| Heat Number - 2 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 2 | 5 | Charlotte BROWNLESS | 12 | Lincoln Trident Swimming Academy | 52.17 | |
| 3 | 7 | Remi BERRY | 12 | City of Linc Pentaqua SC | 51.87 | |
| 4 | 9 | Robyn STEEL | 13 | City of Linc Pentaqua SC | 52.35 | |
| 5 | 8 | Annie WEBSTER | 12 | Grantham SC | 51.41 | |
| 6 | 6 | Lucy BARRATT | 13 | Gainsborough Dolphins SC | 52.23 | |
| 7 | 4 | Florence HENDERSON | 13 | Lincoln Vulcans SC | 51.15 | |
| Heat Number - 3 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 11 | Everlyn TAYLOR | 12 | City of Linc Pentaqua SC | 50.59 | |
| 2 | 13 | Freya SHARPE | 12 | Lincoln Vulcans SC | 48.02 | |
| 3 | 15 | Lucy ABBOTT | 12 | Grantham SC | 47.98 | |
| 4 | 17 | Jessica HALL | 12 | Grantham SC | 47.08 | |
| 5 | 16 | Ava MALLOWS | 12 | Louth Dolphins SC | 47.74 | |
| 6 | 14 | Isla LORMOR | 12 | Gainsborough Dolphins SC | 47.39 | |
| 7 | 12 | Olivia KING | 12 | Deepings SC | 48.47 | |
| 8 | 10 | Miley RICHARDSON | 13 | Lincoln Vulcans SC | 49.31 | |
| Heat Number - 4 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 19 | Darcey WOOD | 11 | Grantham SC | 46.50 | |
| 2 | 21 | Amy BLOW | 11 | City of Linc Pentaqua SC | 45.84 | |
| 3 | 23 | Erin ARCHER | 11 | City of Linc Pentaqua SC | 44.82 | |
| 4 | 25 | Suzanna BURKE | 11 | Louth Dolphins SC | 40.77 | |
| 5 | 24 | Amy PALMER | 11 | City of Linc Pentaqua SC | 44.54 | |
| 6 | 22 | Isabella HALL | 11 | Grantham SC | 47.57 | |
| 7 | 20 | Emily TALKES | 12 | Lincoln Vulcans SC | 46.38 | |
| 8 | 18 | Molly CRAUGHAN | 12 | Lincoln Vulcans SC | 45.94 | |
| Heat Number - 5 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 27 | Karolina PARKINSON | 10 | Lincoln Vulcans SC | 42.63 | |
| 2 | 29 | Amy TAYLOR | 11 | Grantham SC | 42.61 | |
| 3 | 31 | Eliza BARTON | 05 | Louth Dolphins SC | 40.77 | |
| 4 | 33 | Isobel ALLSOP | 10 | Grantham SC | 40.04 | |
| 5 | 32 | Isabelle MCCORKELL | 08 | Gainsborough Dolphins SC | 42.86 | |
| 6 | 30 | Maisie MATTHEWS | 11 | Louth Dolphins SC | 41.05 | |
| 7 | 28 | Millie BAILEY | 09 | Grantham SC | 43.13 | |
| 8 | 26 | Sophie COOKSEY | 10 | Louth Dolphins SC | 41.68 | |
| Heat Number - 6 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 35 | Madison LAMB | 06 | Lincoln Vulcans SC | 40.17 | |
| 2 | 37 | Alexandra BULAT | 06 | Lincoln Vulcans SC | 38.25 | |
| 3 | 39 | Gracie-May COLE | 08 | City of Linc Pentaqua SC | 40.05 | |
| 4 | 41 | Hannah BRUCE | 09 | South Lincs Competitive SC | 41.34 | |
| 5 | 40 | Rianna ABBOTT | 08 | Grantham SC | 41.41 | |
| 6 | 38 | Lucy WILSON | 10 | South Lincs Competitive SC | 41.89 | |
| 7 | 36 | Alexa WRIGHT | 08 | Grantham SC | 42.36 | |
| 8 | 34 | Charlotte HODGIN | 08 | City of Linc Pentaqua SC | 40.73 | |
| Heat Number - 7 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 43 | Holly GILES | 06 | Louth Dolphins SC | 40.30 | |
| 2 | 45 | Kitty LAMB | 11 | South Lincs Competitive SC | 39.33 | |
| 3 | 47 | Isla GRAY | 10 | Grantham SC | 40.73 | |
| 4 | 49 | Helena FIELD | 09 | Louth Dolphins SC | 37.36 | |
| 5 | 48 | Evie DICKINSON | 08 | Louth Dolphins SC | 41.95 | |
| 6 | 46 | Megan LAMB | 09 | Lincoln Vulcans SC | 39.18 | |
| 7 | 44 | Lilli-Rose CARR | 09 | City of Linc Pentaqua SC | 38.75 | |
| 8 | 42 | Emilie WEBB | 10 | Grantham SC | 41.20 | |
| Heat Number - 8 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 51 | Olivia SPENCER | 06 | Lincoln Vulcans SC | 39.30 | |
| 2 | 53 | Lucy CARTER | 08 | Louth Dolphins SC | 38.53 | |
| 3 | 55 | Ruby WARING | 06 | Louth Dolphins SC | 39.20 | |
| 4 | 57 | Evie LILLEY | 09 | Lincoln Vulcans SC | 37.84 | |
| 5 | 56 | Katie MALONEY | 97 | Lincoln Vulcans SC | 38.68 | |
| 6 | 54 | Grace TWILTON | 08 | Lincoln Vulcans SC | 38.57 | |
| 7 | 52 | Charlotte BEMROSE | 08 | Louth Dolphins SC | 38.41 | |
| 8 | 50 | Skye HOLMES | 10 | Louth Dolphins SC | 38.60 | |
| Heat Number - 9 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 61 | Sophie WARD | 09 | Grantham SC | 39.71 | |
| 2 | 67 | Grace TURNER | 07 | Grantham SC | 39.47 | |
| 3 | 73 | Madeleine MACKAY | 98 | Lincoln Vulcans SC | 36.61 | |
| 4 | 79 | Madeleine SMIRTHWAITE | 08 | City of Linc Pentaqua SC | 34.92 | |
| 5 | 76 | Chloe HOPKINSON | 05 | Grantham SC | 37.16 | |
| 6 | 70 | Megan BROWN | 09 | Grantham SC | 38.16 | |
| 7 | 64 | Casey CLEAVER | 06 | City of Linc Pentaqua SC | 38.13 | |
| 8 | 58 | Suzanne HEGG | 70 | Lincoln Vulcans SC | 39.57 | |
| Heat Number - 10 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 62 | Beatrice FINCH | 06 | South Lincs Competitive SC | 36.68 | |
| 2 | 68 | Sigourney BOLTON | 09 | South Lincs Competitive SC | 37.80 | |
| 3 | 74 | Jessica WHEATON | 07 | Skegness ASC | DN:C . | |
| 4 | 80 | Bethany WALKER | 00 | Gainsborough Dolphins SC | 33.88 | |
| 5 | 77 | Charlotte WRIGHT | 05 | Louth Dolphins SC | 35.52 | |
| 6 | 71 | Grace MACDONALD | 09 | Grantham SC | 37.23 | |
| 7 | 65 | Charlotte CIUBERKYTE | 06 | South Lincs Competitive SC | 37.04 | |
| 8 | 59 | Wynifred OWEN | 08 | City of Linc Pentaqua SC | 39.06 | |
| Heat Number - 11 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 63 | Evie TURNER | 06 | Grantham SC | 40.40 | |
| 2 | 69 | Mia COPPING | 07 | Lincoln Vulcans SC | 38.39 | |
| 3 | 75 | Alice-Mae DOWNS | 09 | Lincoln Vulcans SC | 36.85 | |
| 4 | 81 | Katie FOUNDS | 06 | City of Linc Pentaqua SC | 33.44 | |
| 5 | 78 | Olivia ANSTEY | 08 | Louth Dolphins SC | 34.24 | |
| 6 | 72 | Tiegan GRAY | 07 | Gainsborough Dolphins SC | 36.65 | |
| 7 | 66 | Isabella WALTER | 09 | Louth Dolphins SC | 38.00 | |
| 8 | 60 | Daniela BRINGEMAN | 07 | South Lincs Competitive SC | 39.01 | |