MRCS Eng 1881, FRCS 1922; LRCP Edin and LM 1884.
Coates settled in general practice in Moss Side in 1884. He played an important role in the development of Army Medical Services, especially recruitment in the North West. Coates was instrumental in forming the Manchester Volunteer Medical Staff Corps in 1886. After the first world war, he founded the Totally Disabled Soldiers' Homes at Broughton and Southport, and in 1924 established the Barrowmore Tuberculosis Colony. He founded the East Lancashire Branch of the British Red Cross Society and was awarded the Red Cross Society's certificate of honour in 1961. Coates was created KCB in 1930 and appointed a knight in 1960. He was secretary and president of Manchester Medical Society and president of the Section of Venereal Diseases of the BMA. Coates retired from practice when he lost his sight in 1953 and died in Stretford Memorial Hospital on 13 January 1962.