Quebecers who shop at major grocery chains will have to pay five cents per plastic bag, starting Wednesday.

Loblaw, Provigo and Maxi stores across the province enacted the policy in an effort to convince customers to switch to reuseable bags.

The move is expected to reduce the number of bags sent to landfills each year by a billion, according to environmental groups.

But the companies could be doing more, according to Montreal environmentalist Daniel Green.

"It's a bit of greenwashing," he said. "If Loblaw, Provigo wanted to do the right thing, they would just ban the plastic bags" and offer reusable cloth bags for free, Green said.

Each plastic bag costs about a cent to manufacture. The grocery retailers said they will pass along a portion of any profit to the World Wildlife Fund.