Greater tax cuts for low and middle income earners have been locked in after the laws passed the parliament.
Labor's revamped stage three tax package cleared the Senate on Tuesday after passing the lower house earlier this month.
Australians earning less than $150,000 will receive a greater tax cut and those earning more than $150,000 will still receive a tax cut, but less than they would have in the original stage three reform.
The coalition wouldn't stand in the way of lower taxes and relief, opposition finance spokeswoman Jane Hume told parliament.
"But that doesn't mean we condone the mistruth that was told," Senator Hume said, referring to the government backflipping on its position not to touch the initial tax package.
The senator also questioned why the government needed $40 million to advertise its tax package, especially given Australians don't have to do anything to claim the lower rates.
Senator Hume chastised the government for ramming through the legislation this week despite it not coming into effect until July 1, saying it was a political ploy to win the upcoming Dunkley by-election this weekend.
"Why are they running out of time? I'll give you one guess, and it starts with the letter D," she said.
"They are running scared because the people of Dunkley have expressed white-hot anger towards this government."
The Greens wanted the legislation referred to a committee that would report back on March 25 but failed to get support in the Senate.
They also pushed for the government to redesign the package.
Putting in place a tax offset for low and middle income earners of up to $3729 for people earning up to $180,000, and stripping the planned tax cuts for people earning above $205,000 would pump $80 billion into the budget over 10 years, they argued, citing costings from the Parliamentary Budget Office.
Prime Minister Anthony Albanese defended the push to pass the legislation this week, telling parliament Australians deserved cost of living relief.
"Our government wants to deliver a tax cut for every Australian taxpayer, all 13.6 million of them," he said.
"We want people to keep more of what they earn."
The opposition has flagged bringing a tax policy in line with the original stage three reforms to the next election.
Aspects of the initial stage three package Labor cut included the abolishment of the 37 per cent tax rate.
Scrapping the 37 per cent rate and tinkering with thresholds would leave the coalition with tens of billions of dollars to find to balance the budget.
Australian Associated Press
