Born in 1949, Khalid Bin Mahfouz was the second son of Salem Bin Mahfouz (d. 1994), the founder of the National Commercial Bank of Saudi Arabia. He was born in and was a citizen and resident of Saudi Arabia, where he died in August 2009. His widow, Na’elah Kaaki, is a descendant of one of the original partners of Salem Bin Mahfouz in NCB. They had three children: 2 sons, Abdulrahman and Sultan, and a daughter, Eman.