Candidates wishing to contest Malcolm Turnbull's former seat of Wentworth have 10 days left to get their nominations in.
The Australian Electoral Commission on Monday said the writ had been received for the Wentworth by-election to be held on October 20.
The rolls for voters living in the eastern suburbs electorate close next Monday with candidate nominations due by midday on September 27. Early voting for the Sydney seat will start on October 2.
High-profile independent Kerryn Phelps on Monday revealed she wouldn't be doing any preference deals as she attempts to take the seat off the Liberals for the first time in the party's history.
The City of Sydney councillor, who announced on Sunday her intention to run in the by-election, told ABC radio she wouldn't be directing preferences on her how-to-vote cards.
"The people of Wentworth are very intelligent and well-informed voters and I think they will make their minds up about who they want to represent them and I hope that the preference flow does head my way," Dr Phelps said.
"But I don't have any intention of allocating preferences. People should be able ... to figure out who they want to preference after me."
Dr Phelps did say, however, that if voters wanted to send a message to the Liberal Party "they would be putting the Liberals last on the ticket".
The local doctor and marriage equality activist poses the biggest threat to Liberal candidate Dave Sharma who was pre-selected by the party late last week.
Labor's candidate is Tamarama Surf Lifesaving Club president Tim Murray.
Former prime minister Mr Turnbull won the blue-ribbon seat with a margin of more than 17 per cent in the 2016 by-election.
