A by-election for the Australian House of Representatives seat of Fremantle took place on Saturday 28 July 2018, following the resignation of incumbent Labor MP Josh Wilson. In early counting, within 90 minutes of the close of polls, the Australian Broadcasting Corporation's psephologist Antony Green's electoral computer had predicted Labor to retain the electorate with an increased margin. It is notable for being the first time that a Liberal Democrats candidate won a two-candidate-preferred spot in a federal election.