'STL' was the designation of Allied convoys (together with a numerical and sometimes a literal suffix) plying the route from Freetown, Sierra Leone, via Takoradi, Gold Coast, to Lagos, Nigeria, and as such reciprocals of the 'LS' series (September 1943/September 1944).

The first of 33 such convoys was STL.1 of 10/15 September 1943 with the 8,351-ton Belgian Elisabethville and 3,445-ton British New Northland, which were escorted by the sloops Enchantress, Leith, Lowestoft, Sandwich and Wellington, and corvettes Anchusa, Columbine and Violet. The last was STL.31 of 24/30 September 1944 with the 4,712-ton British Capo Olmo, 6,082-ton British Congonian, 5,013-ton British David Livingstone, 4,557-ton British English Monarch, 7,134-ton British Fort Anne, 4,651-ton Norwegian Gabon, 4,992-ton British MacGregor Laird, 5,962-ton Dutch Melampus, 7,130-ton British Mount Douglas Park, 6,770-ton British Silversandal and 5,348-ton British Tolten, which were escorted by the sloop Wellington, corvette Woodruff, and patrol vessels Kilchattan and Kilchrenen.