Terry was born and educated in London. During National Service in the Royal Air Force he qualified as a Russian interpreter. He subsequently worked as an Immigration Officer in the London Docks, before moving to the main part of the Home Office.
During his career he served as a member of the Cabinet Office Secretariat and as Principal Private Secretary to a Cabinet Minister. He also served as head of personnel in the Home Office. Shortly before his retirement as a Deputy Under-Secretary of State he was appointed a Companion of the Order of the Bath for services to the Home Office.
He is an enthusiastic amateur artist, and a number of his paintings feature on the Biddenham Heritage Trail boards. He has lived in Biddenham since 2008 and became a member of the Parish Council in 2012.