William McCormick may refer to:
William McCormick (diplomat) (born 1939), American diplomat William McCormick (businessman) (1742–1815), Scottish-born merchant in North Carolina William McCormick (Upper Canada politician) (1784–1840), Canadian businessman, author and politician William McCormick (MP) (1801–1878), Conservative Londonderry City MP William E. McCormick (1831–1900), American lawyer, businessman, and politician from New York William Grigsby McCormick (1851–1941), American businessman William Sanderson McCormick (1815–1865), businessman from Virginia operated reaper business in Chicago William McCormick (literary scholar) (1859–1930), Scottish-born scholar and educational administrator Barry McCormick (William Joseph McCormick, 1874–1956), American baseball player Bill McCormick (Canadian football) (born c. 1928), Canadian football player Fergie McCormick (William Fergus McCormick, 1939–2018), New Zealand rugby player William McCormick (physician), Canadian physician and nutritionist
See also William M. Blair (William McCormick Blair, 1884–1982), American financier William McCormick Blair Jr. (1916–2015), American diplomat William McCormack (disambiguation)