Sussex 4 is an English level 12 rugby union league traditionally divided into two regional divisions.

It is run by the Sussex Rugby Football Union and features teams from this county.

Promoted teams move up to Sussex Oranjeboom Division 3 and there is no relegation.

Both divisions were ranked at tier 12 of the English league system, with promotion to either Sussex 2 East and Sussex "Oranjeboom" 2 West and, as it was the lowest regional division, there was no relegation.

The division would be renamed Sussex "Late Red" 4 West and would sit at tier 12 of the league system.