MRCS LRCP 1922, MRCP 1925; MB BS Lond 1924, MD 1926.
Snell was born in London on 28 May 1901, the son of a pharmacist. He was educated at King's College Hospital where he held junior appointments before being RMO at St Marylebone Hospital, London, from 1924 to 1927. Snell later entered general practice in Cheshire, and from 1935 was physician to Altrincham General Hospital. He held this appointment until his retirement in 1966, apart from during the Second World War when he served in India in the RAMC. Snell was a member of MMS.