'SB' (i) was the designation of Allied convoys (together with a numerical and sometimes a literal suffix) plying the route from Sydney, Nova Scotia, to Corner Brook, Newfoundland, and as such reciprocals of the 'BS' (iv) series (May 1942/December 1944).

The first of these 100 convoys was SB.1 of 19 May 1942, and the last was SB.97 of 30/31 December 1944).