Labor and the coalition have ruled out a future root-and-branch review of the tax system, both having been burned by such inquiries over the past decade.
At the first treasurers' debate of the campaign, Labor's Chris Bowen said the coalition's white paper process initiated by Tony Abbott had come up with "zero".
But Mr Bowen did not favour revisiting tax reform along the lines of Labor's Ken Henry review.
"I understand the argument for root and branch and holistic reform ... but history teaches us that proper tax reform comes from hard work, dealing with issues as you go," he told the National Press Club on Friday.
Trying to fix everything at once made the problem too hard.
However, Labor was going into the election with some "controversial plans" such as changes to negative gearing and capital gains tax and raising taxes on tobacco.
Treasurer Scott Morrison said the May 3 budget was the government's tax reform plan, stemming from a number of submissions to the white paper process.
Tax reform was a "never-ending process".
"If we are re-elected ... we'll get straight back on with it," he said.
Mr Bowen said Labor would release its policy costings well before election day, covering not only the next four years but 10 year projections and show what year the budget would return to surplus.
However, Mr Morrison said he would not be making "big bold assertions" like Labor did in government but did not deliver.
"These projections are going to be conditional on the way the economy performs," he said.
"I will be honest with the Australian people and the plan to get the budget back into balance."
Asked where he saw further fat to cut out of the budget, the treasurer pointed to changes to pension eligibility and superannuation concessions as showing how spending could be "fit for purpose".
Mr Morrison said the coalition had released a modest $550 million in election promises so far, all of which had been offset by savings.
Mr Bowen said Labor's promises would be fully funded and fully costed.
The pair could face off again on June 13 on the ABC's Q&A program, after Mr Bowen challenged the treasurer to a second debate.
Australian Chamber of Commerce and Industry chief James Pearson told AAP both the treasurer and shadow treasurer had recognised the challenges facing the economy and had not necessarily ruled out tax reform.
"That's why the chamber proposes a 10-step plan to reclaim our place in the 10 top most competitive countries in the world," he said.
"Both Mr Morrison and Mr Bowen have acknowledged the importance of tax cuts for business.
"We would like to see a bipartisan agreement for our plan for a staged tax cut for all businesses over 10 years - it is sensible and affordable economic policy."
