| Natalie Francis | 53.59 | 1997-01-18 | aged 9 | Barnet Copthall Sprint Meet |
| Joanne Watson | 49.84 | 1998-01-17 | aged 10 | unknown fixture |
| Ashley Murray | 49.19 | 1998-07-19 | aged 9 | Kate Lack Memorial, Barnet Copthall |
| Ashley Murray | 47.73 | 1999-02-20 | aged 10 | Herts Age Groups 20/2/99 |
| Ashley Murray | 46.62 | 1999-06-05 | aged 10 | Colchester Open |
| Ashley Murray | 44.86 | 1999-06-26 | aged 10 | Biggleswade Gala |
| Ashley Murray | 43.11 | 1999-11-27 | aged 10 | Hitchin Open |
| Christie Bays | 41.85 | 2006-10-14 | aged 9 | Speedo League 1 |
| Christie Bays | 41.03 | 2006-11-11 | aged 10 | Speedo League 2 |
| Christie Bays | 40.80 | 2006-12-09 | aged 10 | Speedo League 3 |
| Christie Bays | 40.62 | 2007-01-08 | aged 10 | Herts Major League 1 |
| Christie Bays | 39.78 | 2007-02-23 | aged 10 | Junior schools gala |
| Christie Bays | 39.37 | 2007-04-28 | aged 10 | Jeff Cook inter club gala |
| Christie Bays | 38.66 | 2007-05-18 | aged 10 | Inter County schools gala |