Built in 1896 by William Denny & Brothers at Dunbarton as a replacement for the ill fated Seaford1. She served on the Newhaven-Dieppe service until replaced by the turbine steamer Paris in early 1913 when she was transferred to the French flag and operated with a French crew by the LBSCR's partner, the Administration des Chemins de Fer de l'Etat.
At the start of the war the Sussex was requisitioned for use as a troopship but was returned to civilian service with a French crew in 1915. On service between Folkestone and Dieppe in March 1916 she had her bows blown off when torpedoed by the UB29, giving rise to the 'Sussex Incident'. Beached near to Boulogne she was repaired and reused by the French Navy as a mine sweeper.
The Sussex never returned to the channel service; sold to Greece in 1920 she was scrapped in 1922 after being damaged by fire.
1. The Seaford, built in 1894 by William Denny & Brothers, was the LBSCR's first screw driven passenger steamer. She sank, happily without loss of life, the following year after colliding in thick fog with the SS Lyon, a LBSCR cargo steamer.