October 20 is the date set for the by-election in former prime minister Malcolm Turnbull’s seat of Wentworth.
Speaker Tony Smith announced the date in the House of Representatives.
The by-election was triggered after Mr Turnbull resigned from the Parliament following the Liberal leadership spill that saw him lose the prime ministership.
Labor’s candidate Tim Murray has already been campaigning, while the Liberal pre-selection will be held tomorrow night.
The seat is held by the Liberals on a 17.7 per cent margin, but ABC election analyst Antony Green has said next month’s vote could be a lot closer.
More to come.