The opposition is branding changes to superannuation tax as an attack on aspirational Australians as the treasurer says the new rate is modest.
The concessional tax rate applied to future earnings for balances above $3 million will be lifted from 15 per cent to 30 per cent from 2025/26.
It will impact about 80,000 Australians and is expected to raise $2 billion in the first full year and $3.2 billion over five years, which will go back into the budget rather than be spent.
Treasurer Jim Chalmers says the changes are modest but meaningful.
"Overwhelmingly, this is about one thing, responsible economic management," he told reporters in Canberra on Wednesday.
"The changes are about making superannuation more sustainable by making the tax breaks more affordable."
Shadow treasurer Angus Taylor said the government wasn't being honest about the number of Australians the change would impact with the $3 million threshold not indexed and more people creeping above it as inflation rises.
"This is an attack on aspirational middle Australia," he told reporters in Canberra on Wednesday.
"The Labor Party should be honest about how many Australians who are investing 20, 30, even 40 years ahead of their retirement will really be affected.
"Middle Australia should be deeply worried about the desire for this government to tax Australians."
But Mr Taylor wouldn't commit to repealing the legislation if elected. He also wouldn't comment on whether the opposition would negotiate with Labor over indexation or a higher threshold.
"I support government's keeping their election promises and we won't resile from that position," he said.
Dr Chalmers added the government had struck the right balance with the $3 million threshold instead of lowering it to boost revenue.
Mr Taylor is being accused of being obstructionist, with comments he made in 2016 about a fairer taxation system resurfacing.
"Those of us who can afford to pay should be paying our fair share," he said at the time.
"Some people are contributing millions of dollars into super and it is totally inappropriate someone who has contributed millions and millions of dollars continues to get those 15 per cent tax concessions."
Dr Chalmers has also ruled out putting the savings back into the system by adding super to paid parental leave.
He said while it was the government's intention to add super to the leave, it wasn't something that was affordable at the moment.
"This change is about budget repair."
Prime Minister Anthony Albanese said it was hard to argue super accounts with balances of $3 million or more were about "actual retirement incomes".
"There are 17 Australians who have over $100 million in their superannuation accounts and one has over $400 million," he told ABC radio.
"Now most Australians will would agree that's not what superannuation is for, that's not about providing for people's retirement incomes."
Mr Albanese ruled out scrapping capital gains tax exemptions on the family home to raise more revenue.
"We are not going to impact the family home, full stop, exclamation mark," he said.
But Mr Taylor called on the government to categorically rule out any changes to negative gearing after the treasurer said it "isn't something the government is considering".
Greens leader Adam Bandt, whose party's Senate support will be needed to pass the changes, said he would discuss the plan with Labor, but the "modest proposal" ignored other more responsible budget policies.
"Let's look at reining in the stage three tax cuts," he said.
