SEAA Under 20 and Under 15 Inter-Counties Championships
This competition was between all the 19 constituent counties in the South of England Athletic Association region: Bedfordshire, Berkshire, Buckinghamshire, Cambridgeshire, Cornwall, Devon, Dorset, Essex, Hampshire, Hertfordshire, Kent, Middlesex, Norfolk, Oxfordshire, Somerset, Suffolk, Surrey, Sussex and Wiltshire.
It was replaced in 2022 by the SEAA Senior/Under 20 Inter-Counties Championships and the SEAA Under 17/Under 15 Inter-Counties Championships.
Previous years' results
Under 20 Men and Women
| Venue and Date | Under 20 Men | Under 20 Women |
| Barnet Copthall, 26 August 2007 | 5th | 8th |
| Barnet Copthall, 24 August 2008 | 4th | 14th |
| Watford, 30 August 2009 | 6th | 13th |
| Barnet Copthall, 28 August 2010 | 5th | 12th |
| Abingdon, 27 August 2011 | 3rd | 3rd |
| Abingdon, 26 May 2012 | 2nd | 6th |
| Allianz Park, Barnet, 11 August 2013 | 5th | 7th |
| Allianz Park, Barnet, 3 August 2014 | 7th | 7th |
| Allianz Park, Barnet, 23 August 2015 | 3rd | 13th |
| Horspath, Oxford, 21 August 2016 | 3rd | 8th= |
| Horspath, Oxford, 9 September 2017 | 5th= | 10th= |
| Horspath, Oxford, 1 September 2018 | 9th | 3rd |
| Horspath, Oxford, 7 September 2019 | 3rd= | 4th |
| No competition in 2020 | ||
| Horspath, Oxford, 11 September 2021 | absent | absent |
Under 15 Boys and Girls
| Venue and Date | Under 15 Boys | Under 15 Girls |
| Barnet Copthall, 26 August 2007 | 6th | 3rd |
| Barnet Copthall, 24 August 2008 | 6th | 3rd |
| Watford, 30 August 2009 | 5th | 8th |
| Barnet Copthall, 28 August 2010 | 6th | 12th |
| Abingdon, 27 August 2011 | 1st | 3rd |
| Abingdon, 26 May 2012 | 1st | 1st |
| Allianz Park, Barnet, 11 August 2013 | 3rd | 4th |
| Allianz Park, Barnet, 3 August 2014 | 5th | 10th |
| Allianz Park, Barnet, 23 August 2015 | 6th | 6th |
| Horspath, Oxford, 21 August 2016 | 2nd= | 4th |
| Horspath, Oxford, 9 September 2017 | 2nd | 6th |
| Horspath, Oxford, 1 September 2018 | 3rd | 2nd |
| Horspath, Oxford, 7 September 2019 | 11th | 3rd |
| No competition in 2020 | ||
| Horspath, Oxford, 11 September 2021 | absent | absent |