William McCormick

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 Symington McCormick (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 (doctor), operated a sanatorium on Toronto's Wendigo Creek