Iliffe married Renée Merandon du Plessis, a Mauritian of French descent, on 8 December 1938.
In 1953, Lord Iliffe and his wife purchased Basildon Park, a Palladian mansion near Reading, Berkshire with views over the Thames Valley.
Lord Iliffe was deeply interested in the arts and architecture, and their restoration of Basildon Park drew inspiration from a wide circle of friends including Winton Aldridge, Ronald Tree and Graham Sutherland.
[5] On the completion of the restoration, Iliffe presented the house with a large endowment, for its future upkeep, to the National Trust.
Following the donation of Basildon Park to the National Trust, Lord and Lady Iliffe remained as tenants, eventually converting the mansion's former laundry wing into a self-contained house.