| Mark Aldwinckle | 1:16.12 | 1996-03-02 | aged 10 | Age Groups |
| Mark Aldwinckle | 1:15.03 | 1996-06-23 | aged 10 | Club championships |
| Mark Aldwinckle | 1:11.88 | 1996-09-29 | aged 10 | Harlow Open |
| Mark Aldwinckle | 1:11.44 | 1997-03-15 | aged 11 | Age Groups |
| Mark Aldwinckle | 1:11.38 | 1997-07-06 | aged 11 | Club championships |
| Greg Lasenby | 1:05.34 | 1998-05-16 | aged 12 | unknown fixture |
| Edward Burrell | 1:04.56 | 2001-09-30 | aged 12 | Harlow Open session 4 |
| Edward Burrell | 1:03.82 | 2001-12-01 | aged 12 | Speedo League Round 3 |
| James Sutherland | 1:03.38 | 2004-09-26 | aged 12 | Harlow Open |
| James Cook | 1:02.97 | 2011-11-27 | aged 12 | Hitchin Open |
| James Cook | 1:02.36 | 2012-01-21 | aged 12 | Biggleswade Open Day 1 |