Shoppers at New World, Four Square and Pak 'n' Save will pay for plastic bags from August as part of an environmental campaign.
Shoppers will be charged 5 cents a bag at the supermarkets owned by the Supermarket giant, Foodstuffs NZ.
Managing director Tony Carter said although there would be
a saving for the company, there had been no business case researched and the amount of savings was unknown.
He said the company planned to make a contribution to an "environment initiative" but had not decided on an organisation.
North Island Pak 'n' Save shoppers have been paying for plastic bags for about 20 years.
Mr Carter said Foodstuffs had reduced the use of plastic bags by 19 per cent since July 2007 with workers asking shoppers if they needed a plastic bag and supermarkets selling re-usable shopping bags.
He said the 19 per cent reduction amounted to a saving of 50 million bags.
Foodstuffs supermarkets use 270 million bags a year.
"We have looked at the overseas experience in countries such as Ireland where a charge has reduced plastic bag use by 90 per cent. We have also taken into consideration the communities' opinion and it is clear that a charge for plastic bags is the best way forward," he said.
He said he thought shoppers would support the charges for plastic bags and despite the competition at Progressive enterprises - Foodtown, Countdown and Woolworths - giving away free bags, he did not think that it would cost his company customers.
Mr Carter said a trial in Australia found there was an 80 percent reduction in plastic bag consumption when shoppers faced a charge and customers turned to using reusable bags.
In a written statement to nzherald.co.nz, Progressive Enterprise spokesman Bill Moore said the company, which operates Foodtown, Countdown and Woolworths, had "not yet made any decision" about plastic bags.
