Brett died on 12 September 1995 at his home in Clapham, London, from heart failure. His heart valves had been scarred by rheumatic fever contracted as a child.[38] He was cremated and his ashes were given to his family.
One of his elder brothers, John, who was a minister, spoke at his youngest brother's memorial service on 29 November 1995.
Mel Gussow wrote in an obituary for The New York Times, "Mr. Brett was regarded as the quintessential Holmes: breathtakingly analytical, given to outrageous disguises and the blackest moods and relentless in his enthusiasm for solving the most intricate crimes.