William MacGillivray (14 December 1891 – 15 November 1975) was an Australian politician.
He was an independent member of the South Australian House of Assembly from 1938 to 1956, representing the electorate of Chaffey .
He fought with the Royal Horse Artillery in Egypt and Palestine during World War I, but suffered badly from malaria when he returned home.
He migrated to South Australia in 1922, taking advantage of a free passage offered to returned soldiers and hoping that the climate would improve his health.
[5] MacGillivray was eventually defeated by Liberal and Country League candidate Harold King at the 1956 election after the LCL and the Labor Party exchanged preferences in order to dislodge him, a decision that saw an "intense struggle" within the LCL at the time.