| Year | Club name | Why? | | Year | Club name | Why? |
| 2008 | Chelmsford City | Promoted as champions of Isthmian League | | 2022 | Worthing | Promoted as champions from Isthmian League Premier Division |
| 2011 | Eastbourne Borough | Relegated after finishing 23rd in Conference | | 2023 | Aveley | Promoted via play-offs from Isthmian League Premier Division |
| 2012 | Bath City | Relegated after finishing 23rd in Conference | | 2023 | Maidstone United | Relegated after finishing 24th in National League |
| 2014 | Hemel Hempstead Town | Promoted as champions from Southern League | | 2023 | Torquay United | Relegated after finishing 21st in National League |
| 2014 | St Albans City | Promoted via play-offs from Southern League | | 2023 | Truro City | Promoted via play-offs from Southern League Premier League South |
| 2016 | Hampton & Richmond Borough | Promoted as champions from Southern League | | 2023 | Weston-super-Mare | Promoted as champions from Southern League Premier League South |
| 2016 | Welling United | Relegated after finishing 24th in National League | | 2024 | Boreham Wood | Relegated after finishing 21st in National League |
| 2017 | Chippenham Town | Promoted as champions of Southern League | | 2024 | Chesham United | Promoted as champions from Southern League Premier Division South |
| 2018 | Slough Town | Promoted via play-offs from Southern League | | 2024 | Dorking Wanderers | Relegated after finishing 23rd in National League |
| 2019 | Tonbridge Angels | Promoted via play-offs from Isthmian League | | 2024 | Enfield Town | Promoted via play-offs from Isthmian League Premier Division |
| 2022 | Farnborough | Promoted via play-offs from Southern League Premier Division South | | 2024 | AFC Hornchurch | Promoted as champions from Isthmian League Premier Division |
| 2022 | Weymouth | Relegated after finishing 22nd in National League | | 2024 | Salisbury | Promoted via play-offs from Southern League Premier Division South |