Foster married business partner Wendy Cheesman. She died in 1989, leaving him with four sons. whilst he was greiving, he was also diagnosed with bowel cancer. He next married Indian-born Begum Sabiha Rumani Malik. Sabiha was married to Andrew Knight when she and Foster met. Knight was Chairman of News International. Foster and Sabiha divorced in 1998. Foster is now married to Elena Ochoa, Chairman of the Tate International Council, and founder of Ivory Press. He has five children and three grandchildren.