Labor, the coalition and One Nation are exchanging blows over tax in their campaigns for five federal by-elections.
Tax has become the hottest topic in five federal by-elections as Labor, the Liberals and One Nation trade blows.
The electoral rolls for Perth, Fremantle, Braddon, Longman and Mayo closed on Friday night ahead of July 28's "Super Saturday".
Voters will know the full list of candidates on July 6, with early voting to kick off on July 10.
Labor leader Bill Shorten, who was in the Brisbane seat of Longman on Friday and will be there again over the weekend, says personal income tax cuts that passed this week with One Nation support were the equivalent of a "dodgy cheque".
"In all likelihood, Mr Turnbull won't be around to pay for his forecasts and his promises," Mr Shorten said of the seven-year tax cut package.
The prime minister says he's already thinking about how to fast-track some of the $144 billion in tax cuts, some of which won't be due until 2022 and 2024.
"I would love to think we would be able to bring some of these tax cuts forward if the budget enables it," Mr Turnbull said.
The prime minister says voters have a choice between the government's tax cuts and Labor's policy to deny future cuts to high-income earners.
Labor has promised to repeal the final stage of the plan if it wins the next election.
Meanwhile, Labor is taking aim at One Nation over its potential support for corporate tax cuts and a change to the GST carve-up.
Pauline Hanson says she won't support the relief for businesses unless the government can show it is cracking down on the estimated $100 billion in taxes being avoided by multinational corporations.
The laws, which would reduce the corporate tax rate from 30 per cent to 25 per cent, are slated for debate in the Senate on Monday.
Senator Hanson says she wants a "fairer" way of carving up the GST, including a better deal for Western Australia where her colleague Peter Georgiou is recontesting his Senate seat.
However, Labor says that is code for wanting to take money away from her home state of Queensland.
A report on the GST carve-up is due for release next week, the final sitting of parliament before the by-elections and the long winter break.