'KW' was the designation of Allied convoys (together with a numerical suffix) plying the route from Key West, Florida, to Havana, Cuba, and as such reciprocals of the 'CK' series (September/December 1942).

The first known convoy of the series was KW.21, which departed Key West on 10 September with the 4,762-ton US Bessemer, 1,768-ton Honduran Guardian, 4,302-ton Panamanian Ormondale, 1,938-ton US Pan Orleans, 7,633-ton US Seatrain New Orleans, and Panamanian Typhoon. The last was KW.83 which departed Key West on 13 December with nine unspecified ships.