2024 Hornsby state by-election

A by-election will be held in the New South Wales Legislative Assembly seat of Hornsby in 2024, following the resignation of Liberal Party MP Matt Kean on 18 June 2024.

Background
The by-election was triggered by the resignation of Liberal MP Matt Kean, who served as the state party's deputy leader and as the state's Treasurer under Premier Dominic Perrottet. He held many other ministerial roles under both Perrottet and his predecessor, Gladys Berejiklian. Kean is a member of the party's Moderate faction, and during Perrottet's tenure as Premier was regarded as the faction's de facto leader in New South Wales.

Hornsby is a blue-ribbon seat in northern Sydney, and is one of two of the original post-1927 electoral districts to have only ever been held by the Liberal Party, its predecessors or an independent, the other being Vaucluse.