More than a billion plastic bags are used a year In Ireland. That's 325 per person a year!
Most of them end up littering the streets.
As well as not looking very nice, they can be dangerous to wildlife .
But some Irish shoppers are getting their trolleys in a twist about it.
One shopper said: "It's terrible, it's a disgrace...I feel sorry for the poor people".
Others are more positive: "I think it's a great thing...it's easy to remember to bring your own bags once you get used to it."
The Irish Government thinks it's the best way to cut down on litter and encourage more recycling.
And the money made will be recycled too. It will be pumped into national environmental projects.