Countdown will begin phasing out plastic bags at 10 supermarkets later this month.
From May 21, plastic bags will no longer be available at the stores with customers forced to bring their own bag or purchase a reusable bag.
Changing the habits of customers was the biggest challenge of the plan, Countdown spokeswoman Kiri Hannifin said in a statement..
"We know the biggest barrier to change is to get into a new habit of bringing your own bags. It's so easy to forget," she said.
"Whatever you bring, we'll pack it for you, if you bring a bucket or a wheelbarrow … then that's cool, and if you forget, then we'll have some options available."
Countdown was aware that the change would frustrate some customers but were committed to stopping the 350 million plastic bags a year that are currently used at stores.
"We know it's going to be pretty annoying, but we are committed, because we definitely think it's the right thing to do."
The remaining 172 stores will make the change to being plastic bag-free at the end of the year.
The 10 stores are: Dargaville. Grey Lynn, Richmond Rd, Auckland. Aviemore Dr, Highland Park, Auckland. Roselands, Papakura, Auckland. Northwest, Massey, Auckland. Gisborne. Victoria Ave, Whanganui. Johnsonville Mall, Wellington. Redwoodtown, Blenheim. Ferrymead, Christchurch.
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