'ATM' was the designation of Allied military convoys (together with a numerical suffix) plying the route from Antwerp to the Thames river after delivering supplies and equipment for the Allies' northern group of military forces (US 12^th and British 21^st Army Groups) preparing for the final defeat of Germany (December 1944/June 1945).

The first of these 154 'Antwerp to the Thames Military' convoys was ATM.4 of 5/6 December 1944 with the 7,028-ton British Empire Perdita, 2,852-ton British Empire Sedge, 7,176-ton US James B. Weaver, 7,191-ton US Roger Griswold, 7,219-ton British Samarovsk, 7,219-ton British Sambalt and 7,219-ton British Sampa, escorted by the British destroyers Ludlow and Vivacious.

The last of the convoys was ATM.171 of 31 May/1 June 1945, more than three weeks after Germany’s surrender, with the 7,059-ton British Empire Daring, 7,176-ton British Sambalt and 7,219-ton British Samnesse.