Sixsmith is an occupational surname formerly used by someone who made sickles. Notable people with the surname include:
Arthur Sixsmith (1880–1969), Canadian ice hockey rover and businessman Ed Sixsmith (1863–1926), American baseball catcher Eric Sixsmith (1904–1986), British Army general Garnet Sixsmith (1885–1967), Canadian ice hockey player Jane Sixsmith (born 1967), British field hockey player, Olympic bronze medallist Martin Sixsmith (born 1954), British author, journalist and radio/television presenter Paul Sixsmith (born 1971), Maltese international footballer Rufus Sixsmith, character in 2012 film Cloud Atlas