New Zealand has passed legislation banning zero-hour contracts, in what is thought to be one of the first laws in the developed world to end the use of deals criticised as exploitative.

Opposition Labor MP Iain Lees-Galloway was joined by his political opponents in supporting the Employment Standards Legislation Bill to end the use of the deals under which employees are required to be available for work but have no guaranteed minimum hours.

"To the best of my knowledge it's the first of its type [in the developed world], certainly in terms of the US and UK," Mr Lees-Galloway said.

"It's possible Denmark doesn't have them because these type of contracts are all about exploiting loopholes and I don't think Denmark had the loopholes in the first place."

The bill, which comes into force on 1 April, represents a win for workers, opposition Labour leader Andrew Little said.

"This will be welcome news for those workers who have been forced to sit by the phone and sometimes left with no work to show for it," he said in a statement.

New Zealand's Council of Trade Unions acknowledged those workers who made public their personal stories about the corrosive impact of no security of hours or income.

Labor said under the new legislation, employers can no longer demand that workers be "available all the time for work without providing guaranteed hours in your agreement".