The Fairfield City Council is a local government area in the west of Sydney, in the state of New South Wales, Australia. The council was first incorporated as the "Municipal District of Smithfield and Fairfield" on 8 December 1888, and the council's name was changed to the "Municipality of Fairfield" in 1920, before being proclaimed a city in 1979. The City of Fairfield comprises an area of 102 square kilometres (39 sq mi) and as of the 2021 census had a population of 208,475. The mayor of the City of Fairfield is Cr. Frank Carbone, the first popularly-elected independent mayor of Fairfield.
Fairfield is considered one of the most ethnically diverse suburbs in Australia. At the 2021 census, the proportion of residents in the Fairfield local government area who stated their ancestry as Vietnamese and Assyrian, was in excess of sixteen times the national average. The area was linguistically diverse, with Vietnamese, Arabic, Assyrian Neo-Aramaic, or Cantonese languages spoken in households, and ranged from two times to seventeen times the national averages.