Owned by the same family since it was built in 1569, it is now the home of Lord and Lady Hampden and their three children.
The family embarked on the ambitious restoration project which included structural repairs and the creation of a new entrance hall.
Work included the creation of a Great Door, that sits behind the original medieval oak door which was repaired and retained, and two unstable curved window bays were also rebuilt. Damaged Elizabethan stained glass was sent to a specialist conservator and the gallery ceiling was restored.
Harry Dalmeny, Sotheby’s chairman of UK private clients, said: “Glynde Place is a well-deserved winner… Projects like this mean that people will be able to enjoy and use these houses for many more generations.”
The Historic Houses Association said the project led to opportunities for study by scholars and apprentices.