Turning Auckland into a super city council will save ratepayers up to $113 million a year, a Royal Commission report says.

"There is waste," said the report of the Royal Commission on Auckland Governance, which proposes the biggest overhaul of the Auckland region's local government in 20 years.

It recommends one rates bill, one charge for water and one voice for Aucklanders.

The report says that under the present fragmented system, citizens and businesses are getting poorer services than they want at a higher cost than necessary.

The commission members - retired High Court judge Peter Salmon (chairman), Dame Margaret Bazley and David Shand - are proposing an alternative of significant cost savings by changing the structure of local government before the local body elections in October next year.

Auckland now has a regional council and seven territorial councils - Auckland City, Manukau, North Shore, Waitakere, Rodney, Papakura and Franklin.

The commission estimated efficiency savings of 2.5 per cent to 3.5 per cent of the councils' total $3.2 billion spending this year.

This amounts to gains of $76 million to $113 million a year.

"Sharing of services among councils is limited, yet there is scope for so much more activity in this area," said the commission.

Shared services could include purchasing, information technology, finance, administration, human resources and asset management.

The commission proposes a single region-wide authority, called the Auckland Council.

The Auckland Council - led by a mayor elected by all Aucklanders - would assume all local government responsibilities for the region.

The mayor would have powers to appoint the deputy mayor and chairpersons of each committee of the council, as well as the power to propose the budget.

The regional council and the seven territorial councils would be abolished.

Instead, four urban and two rural local councils would serve a slightly larger area under the Auckland Council, with community representation as their core function.

The commission suggests appointing an establishment board to smooth the changeover. It would report to a Cabinet Committee for Auckland, through a Minister for Auckland.

One suggested benefit of the super-city plan is having one rating system for the region, instead of the present system where councils different ways of calculating rates.

Water and wastewater operations of the abolished councils would be transferred to Watercare Services, now the wholesale water supplier.

It would become owned by the Auckland Council. Water and wastewater charges would be calculated on use, and uniform charges would apply throughout the region.

Bringing all the councils' functions together would cost between $120 million and $240 million over the four-year transition period.

But the commission said that not taking action would lead to higher costs.

The commission was established under the previous government.

Local Government Minister Rodney Hide said the Government would consider the commission recommendations over the next fortnight.

"I see merit in having one Auckland organisation to drive, manage and be responsible for all planning and delivery of services," he said.

"However, I have some concerns about whether the report provides for adequate local representation in our many diverse communities, and I want to look more closely at this issue."