 Mason-Cox holds a Bachelor of Laws degree and a Bachelor of Commerce (Finance) degree from the University of New South Wales, where he was awarded the University Prize for Banking Law.Mason-Cox is married to Wendy Mason-Cox and has four children.In 2006, Mason-Cox stood for Liberal Party preselection for a Southern New South Wales regional ballot position for election the New South Wales Legislative Council prior to the 2007 election, challenging incumbent Patricia Forsythe.