During the American War of Independence, "Defence" served with the Channel Fleet, seeing action at the Battle of Cape St. Vincent in 1780. She was sent out to India in early 1782 as part of a squadron of five ships under Commodore Sir Richard Bickerton, arriving too late for the battles of that year. But in 1783 she took part in the last battle of the war, at Cuddalore. She returned to England at the end of 1785. She was then laid up during the years of peace until the outbreak of the French Revolutionary Wars.