| Heat Number - 1 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 3 | 2 | Kai WATSON | 12 | Deepings SC | 39.98 | |
| 4 | 4 | Jonathan GBYLICZEK | 12 | Lincoln Vulcans SC | 39.66 | |
| 5 | 3 | Arlo HAMER | 12 | City of Linc Pentaqua SC | 39.91 | |
| 6 | 1 | Harvey PHILLIPS | 04 | S4 | Louth Dolphins SC | 51.29 |
| Heat Number - 2 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 6 | Samuel NICHOLS | 12 | Grantham SC | 38.81 | |
| 2 | 8 | Luca HALLAM | 12 | Grantham SC | 38.32 | |
| 3 | 10 | Stanley THURLOW | 12 | Lincoln Vulcans SC | 37.83 | |
| 4 | 12 | Finley ROWDING | 11 | City of Linc Pentaqua SC | 36.65 | |
| 5 | 11 | Zachary WILSON | 12 | Lincoln Vulcans SC | 37.22 | |
| 6 | 9 | Dan PALMER | 13 | City of Linc Pentaqua SC | 38.29 | |
| 7 | 7 | Oliver CLARKE | 12 | Deepings SC | 38.47 | |
| 8 | 5 | Leo OLDERSHAW | 12 | South Lincs Competitive SC | 38.94 | |
| Heat Number - 3 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 14 | Oliver WILKINSON | 12 | Lincoln Vulcans SC | 36.40 | |
| 2 | 16 | Oscar DURANT | 11 | Grantham SC | 36.22 | |
| 3 | 18 | Hugo WARD | 11 | Boston Amateur SC | 36.06 | |
| 4 | 20 | Cezmi MERMUTLU | 11 | Louth Dolphins SC | 35.81 | |
| 5 | 19 | Ryan ANDERSON | 11 | Gainsborough Dolphins SC | 35.98 | |
| 6 | 17 | Francesco MONACO | 12 | South Lincs Competitive SC | 36.10 | |
| 7 | 15 | Kieran BLOOR | 11 | City of Linc Pentaqua SC | 36.29 | |
| 8 | 13 | Joel SADLER | 11 | Grantham SC | 36.50 | |
| Heat Number - 4 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 22 | Henry MASON-SMITH | 11 | Louth Dolphins SC | 35.66 | |
| 2 | 24 | Harry ELLIS | 11 | Louth Dolphins SC | 34.10 | |
| 3 | 26 | Aaron SADLER | 10 | South Lincs Competitive SC | 33.50 | |
| 4 | 28 | Robert WASHBROOK | 10 | Lincoln Vulcans SC | 33.08 | |
| 5 | 27 | Henry SEAGROATT | 11 | Louth Dolphins SC | 33.28 | |
| 6 | 25 | James HUCKLE | 11 | Lincoln Vulcans SC | 33.81 | |
| 7 | 23 | Robbie DUFF | 11 | Lincoln Vulcans SC | 34.84 | |
| 8 | 21 | Dominic MCLAUGHLIN | 11 | Louth Dolphins SC | 35.75 | |
| Heat Number - 5 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 30 | Charlie WARD | 10 | South Lincs Competitive SC | 32.27 | |
| 2 | 32 | James CASH | 10 | Deepings SC | 32.16 | |
| 3 | 34 | Jacob HEGG | 10 | Lincoln Vulcans SC | 30.34 | |
| 4 | 36 | Matthew TOMPKINSON | 09 | Louth Dolphins SC | 30.05 | |
| 5 | 35 | Frank LAMB | 09 | South Lincs Competitive SC | 30.30 | |
| 6 | 33 | Charlie BISBY | 11 | South Lincs Competitive SC | 31.34 | |
| 7 | 31 | Oliver GARNER | 10 | City of Linc Pentaqua SC | 32.20 | |
| 8 | 29 | Jacob TURNER | 10 | Boston Amateur SC | 33.00 | |
| Heat Number - 6 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 38 | Matteo MONACO | 09 | South Lincs Competitive SC | 29.82 | |
| 2 | 40 | Kieran NG | 10 | South Lincs Competitive SC | 29.35 | |
| 3 | 42 | Zach HOPKINSON | 09 | Grantham SC | 29.28 | |
| 4 | 44 | Freddie TRAGNI | 09 | City of Linc Pentaqua SC | 29.01 | |
| 5 | 43 | Morgan FARRAR | 09 | City of Linc Pentaqua SC | 29.25 | |
| 6 | 41 | James THOMAS | 10 | Gainsborough Dolphins SC | 29.30 | |
| 7 | 39 | Layton ANNISON-SNOWDEN | 09 | Louth Dolphins SC | 29.64 | |
| 8 | 37 | Daniel HEPPLESTONE | 10 | Lincoln Vulcans SC | 29.90 | |
| Heat Number - 7 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 48 | Jack ZERAVICA | 08 | Grantham SC | 27.40 | |
| 2 | 54 | George BERWICK | 03 | Grantham SC | 26.71 | |
| 3 | 60 | Jake ADAMS | 07 | Louth Dolphins SC | 26.38 | |
| 4 | 66 | Thomas BRUCE | 06 | South Lincs Competitive SC | 25.10 | |
| 5 | 63 | Ewan COX | 08 | City of Linc Pentaqua SC | 25.80 | |
| 6 | 57 | Isaac BANHAM | 05 | Skegness ASC | 26.50 | |
| 7 | 51 | Leon BAILEY | 06 | Louth Dolphins SC | 26.92 | |
| 8 | 45 | Jacob FISH | 09 | Grantham SC | 28.77 | |
| Heat Number - 8 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 49 | Oscar GOLDSMITH | 08 | South Lincs Competitive SC | 27.10 | |
| 2 | 55 | Owen HATHWAY | 06 | Grantham SC | 26.68 | |
| 3 | 61 | Ben LORD | 05 | City of Linc Pentaqua SC | 26.30 | |
| 4 | 67 | Charlie MILLER | 05 | Skegness ASC | 24.70 | |
| 5 | 64 | Joseph PARNELL | 07 | City of Linc Pentaqua SC | 25.70 | |
| 6 | 58 | Joshua CLARKE | 08 | Grantham SC | 26.48 | |
| 7 | 52 | Jamie GREEN | 05 | City of Linc Pentaqua SC | 26.78 | |
| 8 | 46 | Oliver JONES | 09 | Lincoln Vulcans SC | 28.40 | |
| Heat Number - 9 | ||||||
| Lane | Comp.No. | Name | YoB | Cat | Club | Time |
| 1 | 50 | Ryan NORTON | 07 | Boston Amateur SC | 26.97 | |
| 2 | 56 | Alfie BISBY | 07 | South Lincs Competitive SC | 26.66 | |
| 3 | 62 | Thomas HEPPLESTONE | 06 | City of Linc Pentaqua SC | 25.82 | |
| 4 | 68 | Ethan RICHES | 03 | City of Linc Pentaqua SC | 24.40 | |
| 5 | 65 | Henry CRUST | 05 | City of Linc Pentaqua SC | 25.20 | |
| 6 | 59 | Alex SADLER | 07 | South Lincs Competitive SC | 26.40 | |
| 7 | 53 | Daniel EVANS | 95 | City of Linc Pentaqua SC | 26.75 | |
| 8 | 47 | Jensen HYLTON | 08 | City of Linc Pentaqua SC | 27.63 | |