'HT' was the designation of Allied convoys (together with a numerical suffix) plying the route from Halifax, Nova Scotia, to Trinidad, and as such reciprocals of the 'TH' series (May/June 1942).

The first of this 'Halifax to Trinidad' series was HT.1 of 22 May/1 June 1942 with the 8,238-ton Norwegian Britamsea, 5,343-ton US Cities Service Fuel, 4,049-ton British John W. Mackay and 9,069-ton British Reginolite. The last of these three tanker convoys was HT.3 of 20/29 June 1942 with he 9,430-ton Norwegian Alar, 9,976-ton Norwegian Britamer, 5,343-ton US Cities Service Fuel, 10,169-ton Panamanian Stanvac Cape Town, 11,404-ton British Vancolite and 7,991-ton US Wallace E. Pratt.