Real hash, Shorten says of super changes

Labor has cast doubt on the Turnbull government's ability to crack down on superannuation tax concessions that have angered some of the coalition support base.

"They've made a real hash of superannuation," Opposition Leader Bill Shorten said on Tuesday.

If elected on Saturday a Labor government would immediately review any changes regarded as retrospective.

Mr Shorten said his economic team has been talking with superannuation funds, financial advisers and retirees about changes.

"This government doesn't know how to implement these changes, it is not clear if the changes are actually implementable."

He cited changes to transition-to-retirement arrangements and a $500,000 cap on non-concessional contributions backdated to 2007.

"They have been at sixes and sevens to explain to people how you calculate your tax records back 10 years," Mr Shorten said of the government.

Labor, despite its concerns, has banked the $3 billion in budget savings the changes create as part of its costings and bottom line forecasts.