When war broke out in September 1914, the Salsette continued her normal routine between Bombay and Aden. In November 1915, she made her first sailing from London to Bombay, taking her place on the Indian or Australian mail routes. In July 1917, sailing from London to Sydney via Bombay, and carrying onboard a large amount of money to pay the British garrison in Egypt, she was hit by a German torpedo some fifteen miles southwest of Portland Bill. Fifty minutes later, she sank. Fifteen members of the crew lost their lives.