The Australian Greens propose a tax on the big four banks for government insurance that would raise up to $A11 billion over the next four years.
The party proposes a levy of 0.2% on all bank assets above $100 billion in return for the federal government's protection to ensure they do not fail.
It would apply to ANZ, Commonwealth Bank, NAB and Westpac, which made a combined $A25 billion in profits last year.
"It is time to ask the big banks that are making record profits to pay a fairer share to the community," Greens deputy leader Adam Bandt told ABC Radio on Friday.
AAP reports the plan has been costed by the independent parliamentary budget office.