William McMaster (24 December 1811 – 22 September 1887) was a Canadian wholesaler, senator and banker in the 19th century. A director of the Bank of Montreal from 1864 to 1867, he was a driving force behind the creation of the Canadian Bank of Commerce of which he was the founding president from 1867 to his death in 1887. He sat in the Senate of Canada from 1867 to 1887 as a Liberal. He also helped found McMaster University in Toronto (later moved to Hamilton), Ontario.