William, Will, Bill, or Billy Montgomery may refer to:
Law and politics
U.S.
William Montgomery (Pennsylvania soldier) (1736–1816), U.S. congressman and judge
William Montgomery (North Carolina politician) (1789–1844), U.S. congressman and physician
William J. Montgomery (1851–1913), South Carolina senator and representative, mayor and lawyer
William Montgomery (Pennsylvania politician, born 1818) (1818–1870), U.S. congressman from Pennsylvania
William Watts Montgomery (1827–1897), American jurist in Georgia
Billy Montgomery (1937–2025), American educator and politician
Bill Montgomery (activist) (1940–2020), co-founder of Turning Point USA
William Dale Montgomery (born 1945), American diplomat
Bill Montgomery (Arizona attorney) (born 1967), American lawyer and jurist in Arizona
Elsewhere
Sir William Montgomery, 1st Baronet (1717–1788), Scottish-born politician in Ireland
William Montgomery (New Zealand politician) (1821–1914), New Zealand MP, minister of education
William Montgomery Jr. (1866–1958), New Zealand MP
American football
Bill Montgomery (halfback) (1923–2003), American football player
Bill Montgomery (quarterback) (born 1949), American football player
Will Montgomery (born 1983), American football center
Other sports
Bill Montgomery (cricketer) (1878–1952), English cricketer
Bill Montgomery (footballer, born 1885) (1885–1953), Scottish footballer
Bill Montgomery (Australian footballer) (1915–1988), Australian rules footballer
Will Montgomery (rugby union) (born 2000), English rugby union player
Others
William Fetherstone Montgomery (1797–1859), Irish obstetrician
William Reading Montgomery (1801–1871), Union Army general in American Civil War
William Bell Montgomery (1829–1904), American farmer, businessman, and editor
William Allen Montgomery (1829–1905), American lawyer, planter and Baptist minister
William Montgomery (cryptographer) (fl. 1918), British cryptographer in World War I
William Thornton Montgomery (1843– 1909), American freedman, businessman, farmer, and community leader