Each year some of the clubs in this division also take part in the RFU Junior Vase - a level 9-12 national competition.

The cancellation of National 5 South at the end of the 1995–96 season meant that Sussex 1 reverted to being a tier 8 league.

The introduction of London 4 South East ahead of the 2000–01 season meant Sussex 1 dropped to become a tier 9 league with promotion to this new division.

Relegation continued to Sussex 2 (briefly two regional divisions) until that league was abolished at the end of the 2003–04 season.

Since the 2000–01 season there has been a play-off between the runners-up of Kent 1 and Sussex 1 for the third and final promotion place to London 3 South East.