Unite Union says while all New Zealand's major fast food chains have now dumped contentious zero-hour contracts, whole industries are still using them.
The union said early this morning that it had reached an agreement with McDonald's to end the contracts, which require workers to be on-call but with no guaranteed work.
Unite national director Mike Treen said it was an historic agreement and a fundamental shift in the employment relationship for the most vulnerable workers in the country.
"I think it was the recognition that New Zealand society has changed. McDonald's is the largest company, so it was the biggest challenge for them, I think."
Listen to Mike Treen
The deal announced today means 80 percent of the hours worked by McDonald's employees - based on what they work in a three-month period - will be guaranteed. A survey on hours worked will also be done every three months.
In a statement, McDonald's confirmed an agreement had been reached and said the guaranteed hours would be offered from 1 October up to a 32-hour weekly cap.
The company said it acknowledged that security of hours was important to its staff, which is why it had agreed to end its zero-hour contracts.
It said it had already agreed in principle to write guaranteed hours into its employment agreements, and had been working on the technical details with the union since early April.
Mr Treen said planned strikes at McDonald's stores around the country today had been called off.
However, he said, in some cases it would be too late to cancel the action so supporters were urged to hold victory celebrations instead.
Law change may be necessary - Unite
Mr Treen told Morning Report the only remaining fast food chain the union would be targeting to get rid of zero-hour contracts would be Wendy's.
But, he added, the union had discovered industries such as security, cleaning and even some city councils appeared to still be using them.
He said the contracts had become a habit for some people and the real solution would be to change the law.
"This attitude that all the flexibility is on the side of the worker and no responsibility on the part of the employer has just got to change. It may need legislative action to ensure these changes."