William Townsend may refer to:
- William Townsend (mayor) (1821–1882), Australian politician
- William Townsend (cricketer) (1821–1891), English cricketer and barrister
- William Townsend (Oneida County, NY) (1848–1919), New York politician
- William A. Townsend (1904–1993), British philatelist
- William Cameron Townsend (1896–1982), American Christian missionary
- William Charles Townsend (1803–1850), English barrister and writer
- William George Paulson Townsend (1868–1941), English artist, designer and writer
- William H. Townsend (1812–1873), former Nova Scotia political figure
- William H. Townsend (1914–2005), American state legislator and optometrist
- William John Townsend (1835–1915), British Methodist minister
- William Kneeland Townsend (1849–1907), U.S. federal judge
- William Richard Townsend (died 1914), British lawyer and colonial administrator
- William T. Townsend, founder and CEO of Barrett Technology
- Bill Townsend (born 1965), businessman
- Bill Townsend (footballer) (1922–1988), English football player and manager