A member of the prominent Halsey family of Hertfordshire, Halsey was educated at Eton and the Royal Agricultural College at Cirencester.
[1][2] He married Viola Georgina Juliet Thorne on 7 August 1976.
Their son is Guy Francis Johnston Halsey, born in 1981.
Halsey is the Lord of the Manor for Hemel Hempstead[3][4] and owner of the Gaddesden Estate, and as such is patron of the Church of St John the Baptist, Great Gaddesden.
[5][6] Halsey also served as president of the Royal Forestry Society 2011–2015.