Fairmount is a hamlet (and census-designated place) in Onondaga County, New York, United States. The Fairmount area was originally part of the New York State Salt Reservation, but was annexed to the town of Camillus in 1834. Prior to that date, census enumerations for Fairmount were included in the town of Onondaga census. The name originates from 1798 when engineer and politician James Geddes built his estate, called "Fair Mount" at the intersection of Genesee Road (now West Genesee Street) and Onondaga Road. During the mid-19th century, the hamlet was known as Tyler.