She spent barely half a year in service, transporting goods for the Allies, from Port Said to the United States, via Suez and Durban.

At just after 8 o'clock in the evening on 8 March James B. Stephens was travelling unescorted when she was spotted and torpedoed by U-160 commanded by Georg Lassen about 150 miles (240 km) northeast of Durban.

The explosion ignited the fuel oil stored in the double bottoms and she began to rapidly sink by the bow.

The other lifeboats were able to pick up all of the men in the water, with the exception of one of the Armed Guards, Vane Irvin Vanderpool, who was not wearing a life jacket and could not swim, and who drowned before he could be rescued.

The remaining 13 survivors were rescued six days after the attack by a South African Air Force crash boat one mile (1.6 km) off Durban, after they were spotted by another aircraft.