'KJ' (i) was the designation of Allied convoys (together with a numerical suffix and in some cases the literal suffix B or F) plying the route from Kingston, Jamaica, to the UK (September/October 1939).

The first of these convoys was KJ.1F of 15/30 September 1939 with the 6,907-ton British Cavina, 5,363-ton British Corrales, 8,587-ton British Indian Prince, 6,618-ton British Inkosi, 5,464-ton British Jamaica Producer, 8,194-ton British Lady Rodney, 5,983-ton British oiler Orangeleaf, 5,820-ton British Port Halifax and 16,737-ton British Rangitata escorted by the light cruiser Orion.

The last of the series was KJ.3 of 4/28 October 1939 with the 8,010-ton British tanker Acavus, 1,977-ton British Amakura, 8,826-ton British tanker Appalachee, 6,568-ton British Athelbeach, 6,989-ton British tanker British General, 11,941-ton British tanker Calgarolite, 11,309-ton British tanker Canadolite, 8,230-ton British Caprella, 9,946-ton French tanker Champagne, 5,792-ton British Chaucer, 8,132-ton British tanker Conus, 8,102-ton British tanker Drupa, 4,358-ton British East Wales, 6,207-ton British Erodona, 4,955-ton British Fresno City, French tanker Frimaire, 4,434-ton British Gryfevale, 5,205-ton British Iddesleigh, 4,573-ton British Imperial Valley, 8,937-ton British tanker Iroquois, 6,401-ton British Laristan, 6,159-ton British tanker Luminetta, French Michigan, 11,309-ton British tanker Montrolite, 6,254-ton British tanker Pellicula, 4,323-ton British Redgate, 4,993-ton British Ridley, 9,967-ton French tanker Roussillon, 4,573-ton British Sacramento Valley, 7,419-ton British tanker San Demetrio, 8,042-ton British tanker San Eliseo, 8,071-ton British tanker San Emiliano, 5,890-ton British tanker San Roberto, 8,965-ton British tanker Schuylkill, 4814-ton British Sheaf Holme, 5,265-ton British Somme, 6,724-ton British tanker Sovac, 4,329-ton Egyptian Star of Alexandria, 7,406-ton British tanker Telena, 4,976-ton British Uffington Court and 4,950-ton British Umberleigh with the notably strong escort provided by the British heavy cruisers Berwick and Effingham, light cruisers Glasgow, Newcastle, Orion and Perth, and destroyers Glowworm, Greyhound, Verity, Versatile, Volunteer and Wolverine, and the French fast battleship Dunkerque, light cruisers Georges Leygues and Montcalm, and destroyers Le Malin, Le Triomphant and L’Indomptable.