Charging for plastic bags cuts usage sharply, national grocery retailer Loblaw Cos. Ltd. said Thursday in announcing the national rollout of a five-cent-a-bag fee, starting April 22.

Company research "revealed that a charge-for-bag strategy is the key driver behind significantly reducing plastic shopping bag use," Loblaw said in a news release.

About four in five Canadians support the idea, the company said, citing a March 2009 poll.

Company stores which have been charging a fee distribute almost 55 per cent fewer bags per $1,000 worth of sales, compared with stores that are not charging.

Providing a rebate to shoppers who brought reusable bags was much less effective, resulting in drop of just four per cent in plastic bag use, the company said.

The pilot program in Toronto reinforces the fee approach, Loblaw said. On Jan. 12, participating stores began charging a nickel for each bag. That resulted in about 75 per cent fewer plastic shopping bags distributed per $1,000 sales in those stores," the company said.

The company is using the slogan "Bring it" to promote its push for fewer plastic bags and more reusable containers. Its target is to divert one billion plastic bags from going into the garbage by the end of the year.

Loblaw is also selling various reusable containers, from purse-sized bags to a shopping bag on wheels that folds into a pouch.

The company is giving part of the money made from plastic bag sales in its corporate stores to support WWF-Canada conservation programs, the release said.

"The remainder of the proceeds will be used to cover the cost of the Loblaw plastic shopping bag reduction program and invested back in the business."

Loblaw has 1,000 corporate and franchised stores in Canada.