2002–03 National Division Three South

The 2002-03 National Division Three South was the third season (sixteenth overall) of the fourth division (south) of the English domestic rugby union competition using the name National Division Three South. New teams to the division included Rosslyn Park who were relegated from the 2001–02 National Division Two while Havant (champions) and Basingstoke (playoffs) were promoted from London Division 1 along with champions of South West Division 1 – Weston-super-Mare. The league system was 2 points for a win and 1 point for a draw. The league system was 2 points for a win and 1 point for a draw with the league champions going straight up into National Division Two and the runners up playing a playoff against the runners up from National Division Three North for the final promotion place.

2002–03 National Division Three South

The 2002-03 National Division Three South was the third season (sixteenth overall) of the fourth division (south) of the English domestic rugby union competition using the name National Division Three South. New teams to the division included Rosslyn Park who were relegated from the 2001–02 National Division Two while Havant (champions) and Basingstoke (playoffs) were promoted from London Division 1 along with champions of South West Division 1 – Weston-super-Mare. The league system was 2 points for a win and 1 point for a draw. The league system was 2 points for a win and 1 point for a draw with the league champions going straight up into National Division Two and the runners up playing a playoff against the runners up from National Division Three North for the final promotion place.