After a six month phase in, New Zealand's ban on single-use plastic bags takes effect tomorrow.
Supermarkets made the switch by the end of last year.
Associate Environment Minister Eugenie Sage says Kiwis really support the move.
She says research found in April last year 56 percent of shoppers surveyed were bringing reusable bags, and that figure rose to 91 percent by September.
"Banning these bags means that we;ll be saving tens of millions of bags going to landfill or getting into rivers and streams and into the oceans, protecting our marine life - fish, seabirds and marine mammals.'
Bin liners, dog poo bags, and the bags used for meat, fruit and vegetables are not included in the ban.
Sage told the Weekend Collective it does include compostable, degradable bags.
"We don't have the facilities around New Zealand to deal with compostable bags, and they don't degrade in home compost heaps."
Sage was unsure about the rules for the stronger plastic bags Countdown has been selling.
Still confused? Here are the five other things you need to know:
There's a precise definition for what's actually banned
The rules apply to any type of plastic less than 70 microns in thickness, that's new or un-used, has carry handles, is provided for carrying sold goods, and is made of bio-based materials like starch. It also covers bags made of plastics that are degradable, biodegradable or oxo-degradable.
These are sometimes marketed as "not plastic". The typical type of bag covered are those offered at supermarkets and stores - the old yellow Pak N Save bags measured about 35 microns, while those from clothing or department stores are usually between 50 and 70 microns.
The bags many people are using now are jute or polypropylene bags, that can be reused over and over.
The Government was encouraging retailers to clarify with their suppliers on the thickness of their bags they offered, and recommended they choose reusable ones.
Over the six-month phase-out period that led up to the law kicking in, supermarkets have already switched away from single-use plastic shopping bags, stopping tens of millions of them from entering circulation.
Kiwis also appear to have adopted the change early, with survey results showing more than 80 per cent of shoppers were bringing their own reusable bags with them as at last September - up from just over half a few months before that.
That said, a Herald survey conducted in central Queen St last week counted what appeared to be five new single-use plastic shopping bags carrying goods out of four shops.
Noel Leeming, Farmers, Daiso Japan, Yummy Jianbing takeaways, Jay Jays, Mirrou and Hannahs all said they would have compliant bags from tomorrow.
The survey counted 25 paper, woven and other types of bags, which would be permitted after Monday.
Many people put smaller purchases in their own bags or into a pocket.
Bio-bags are banned too
Even though bio-based plastic bags are sometimes made from plants, their manufacturing process prevents them from breaking down as quickly or as easily.
Compostable bags, for example, if not composted properly, ended up being a problem too, and not everyone had access to a home compost that could process these bags.
But the Ministry for the Environment has advised that this part of the ban might be revisited if the right infrastructure is developed.
Lots of other types of bags can still be used
People will still be able to buy lightweight barrier bags, like the ones that you get in the deli or butchery, along with bin liners, pet waste bags and nappy bags.
Also exempt were bags used in packaging, like bread bags and pouches for cooked chicken.
The Government's reasoning was that these types of bags were needed for hygiene purposes, and at this stage, it wasn't looking at extending the ban to them.
The rules also didn't apply to long-life...