Born on 21 November 1904 son of Peter Ashcroft he was educated at Knox College and the University of Otago, New Zealand. He came to the United Kingdom for postgraduate study in 1931, after his home town of Napier in North Island had been devastated by an earthquake. He was appointed otological registrar and first assistant in the ear nose and throat department of the Middlesex Hospital, and Bernhard Baron research scholar at the Ferens Institute of Otolaryngology, where he came under the influence of Somerville Hastings and F J Cleminson. In 1939 he was appointed registrar to the ear nose and throat department of the Westminster Hospital. During the war of 1939-45 he served with the RAMC as a specialist in otology and was mentioned in dispatches. During the later part of this service he was stationed at Bari at the time of the explosion of munition ships in the harbour, as a result of which he suffered from traumatic deafness which progressed over the years. After the war he returned to the Westminster Hospital, and later also held appointments at the Westminster Children's Hospital and the Chelsea Hospital for Women. Ashcroft was a keen sportsman and an able cricketer, and at the time of his death was president of the Westminster Hospital Cricket Club. He married first in 1937 Enid Jessie, daughter of James Patrick; there was one son of the marriage. His wife died in 1956, and in 1957 he married secondly Nancy Clarke, who survived him. Ashcroft died suddenly at his home at Horsham on 7 May 1963.