[1][2] The first rugby club in Sussex was Brighton, formed in 1868.

Following the formation of several other clubs in the 1880s, the Sussex Rugby Football Union was formed in 1883, several years prior to the national organisation of which it is now a constituent part, with the most recent members admitted in 2008.

Prior to this they reached the final of the 2017 Bill Beaumont County Championship Division 2 (the first time in the county's history), losing on try count to Oxfordshire (4 tries to 5) at Twickenham Stadium, after an exciting game that finished 29-29.

[4] Sussex currently play in Division 1 of the Gill Burns County Championship having been promoted from Division 2 at the end of the 2017-2018 season after winning the South East Region competition.

In 2019 they reached the final of Division 1 Gill Burns County Championship at Twickenham Stadium (the first in the county's history), losing to Yorkshire 11-27.