Anthony Keck is said to have been born in Randwick, Gloucestershire, where he lived until he married and moved to King's Stanley where he remained for the rest of his life.
He had a considerable practice in Gloucestershire, Worcestershire, Herefordshire and South Wales. He came from a family of Yeoman farmers in the Cheltenham District and was possibly apprenticed to a builder-architect in the area. At the time of his marriage in 1761 he was described as a builder, but when he was given the Freedom of Worcester in 1768 he was Anthony Keck Architect. At this time he was living in Kings Stanley near Stroud, Gloucestershire.
He was helped to secure commissions in Worcestershire by Revd Dr Treadway Nash, author of Collections for the History of Worcestershire. His finest house is considered to be Penrice Castle, Glamorgan. He worked on extensions and alterations to a number of country houses in Gloucestershire, and rebuilt Hill House, now Rodborough Manor, for Sir George Paul.