Leo Stowell was born in New Cross, London, England on 16 March 1891. He was the son of Arthur Stowell, a cashier, and Alice Elizabeth Broomfield and he had two sisters.
First working as an insurance clerk, Stowell joined the Royal Navy in October 1910, training at Victory I before serving aboard the Hercules as an officer’s steward from July to October 1911 before going ashore. He immediately joined the merchant service and served as a waiter aboard Ivernia from late-1911 to February 1912 before joining the Carpathia. In April 1912 Stowell was serving as a waiter aboard the eastward-bound voyage of the Carpathia when that ship rescued the survivors of the Titanic.
Leo later left the sea to work as an aircraft fitter; he was married in 1915 to Ella Mary Hatt (1897-1969) and they raised a family. Living for many years in Sevenoaks, Kent, he died in London on 10 June 1961.