Countdown is to phase out single-use plastic bags at its supermarkets by the end of next year.
The supermarket chain's managing director Dave Chambers said customer research found 83 percent support for phasing out plastic carrier bags.
Mr Chambers said the ban would result in 350 million fewer plastic bags ending up in rubbish tips.
"Now is the right time to take the lead, phase out single-use plastic carrier bags and introduce better options for customers."
The company looked at charging for bags but decided it wasn't the right option for customers or the environment, he said.
SuperValue and FreshChoice and the parent company Progressive Enterprises have also committed to phasing out single-use bags but have not decided on a deadline.
Mr Chambers said customers had adapted well to the company's first plastic free supermarket, on Waiheke Island, which started in May last year.
Greenpeace praised the company for its "bold move".
Greenpeace campaigner Elena Di Palma said it made them the "leader of the pack on plastic reduction".
The environmental group called on Foodstuffs New World to also eliminate single-use bags.
"Banning the bag is the only answer that deals with the terrible impact of plastic pollution on our oceans and sea life," said Di Palma.
"We are now calling on the new government to step in and regulate to completely stamp out single-use plastic bags."
Foodstuffs not following suit
Last month New World put out a survey to customers asking if they would pay 5 cents, 10 cents, or prefer to keep plastic bags free of charge.
There was no option to have no plastic bags.
In a statement Foodstuffs, which owns New World and Pak'nSave, congratulated Countdown on the move.
"It's good to see another retailer taking a stance on targeting a date for removing single use plastic bags," Foodstuffs managing director Steve Anderson said.
He said New World's BagVote stimulated a lot of discussion.
"Our focus continues to be on our total sustainability programme, we are really proud of the way our customers are getting stuck into soft plastic recycling, contributing to more than eight tonnes a week being collected by the programme.
"We're looking forward to the final results of BagVote and immediately introducing some initiatives to help encourage a further reduction of plastic bag usage by our customers, Mr Anderson said.