The spotlight goes on tax on Thursday as the productivity roundtable in Canberra draws to a close.

The third and final day of the federal government’s economic reform summit will focus on tax reform and budget sustainability.

The government went into the federal election in May promising no changes to negative gearing and the capital gains benefit. But those at the forum are still expected to make the case for reform.

Unions are expected to argue for a full suite of tax measures including limiting negative gearing to one investment property, with existing laws to remain for five years.

Union attendees are also pitching a minimum tax rate of 25 per cent for those who earn more than $1 million a year.

Tax expert Dale Boccabella said the Albanese government must consider taking capital gains and negative gearing reform to voters.

“Aspects of the tax system is just unfair and the big one is the capital gains tax discount,” the associate professor of tax law at the University of NSW said.

“If you look at who gets the benefits, it goes to the top end. They don’t need a 50 per cent tax break.”

Boccabella said the tax system’s sustainability must be front and centre on the final day of the roundtable.

“Sustainability and fairness go hand in hand, and underlying that, of course, is generational unfairness,” he said.

“The government should not be criticised for acting on [negative gearing], it should be done in a sustainable way.”

The third day of the summit will include a presentation on budget sustainability by Treasury secretary Jenny Wilkinson.

Grattan Institute chief executive Aruna Sathanapally will deliver a pitch on a better tax system.

Also on the agenda will be how to make government services and spending more efficient.

Treasurer Jim Chalmers said the roundtable had produced consensus for areas of economic reform.

“We’ve already got a big agenda to ease the burden on businesses, cut red tape and build more homes but we’re keen to do more where we can,” he said.

-AAP