English shoppers face a 5p charge for plastic carrier bags from today as part of a Government scheme to reduce litter and protect wildlife.
The scheme in England, the last part of the UK to bring in bag charging, will require shoppers at all supermarkets and large shops to use their own bags or pay the charge.
Environmentalists have welcomed the move, which aims to prevent plastic bags ending up as litter or marine pollution where they can be harmful to wildlife, but have called for a more comprehensive scheme which includes all retailers and all types of bags.
Under the new scheme, retailers with 250 or more full-time equivalent employees will have to charge a minimum of 5p for the bags they provide for shopping in stores and for deliveries, but smaller shops and paper bags are not included.
As a result, campaigners warn that it may not be as successful as more comprehensive bag charging schemes brought in elsewhere in the UK, such as Wales where the number of bags handed out by retailers fell by 79% in the first three years.
Even with the exclusions, the Government expects the scheme to reduce use of single-use carrier bags by up to 80% in supermarkets, and 50% on the high street.
It is also expected to save £60 million in litter clean-up costs and generate £730 million for good causes.
The initiative appears to have the support of the majority of shoppers in England, with 62% thinking it is reasonable to charge 5p for all carrier bags - a 6% increase on 2012, a poll for the Break the Bag Habit coalition of litter charities found.
But the survey found 51% were in support of an even more comprehensive scheme that extended the charge to all retailers.
Friends of the Earth's senior resources campaigner David Powell said: "This charge will significantly reduce the billions of one-use plastic bags handed out in the UK each year - but it should apply to smaller shops too.
"More than half of people living in England and the Association of Convenience Stores are supportive of extending the scheme to all retailers.
"And in Wales, 90% of businesses, both large and small, said that a 5p charge hasn't impacted on their trade."
Environment minister Rory Stewart said: "We're all guilty of taking a carrier bag from a supermarket, storing it somewhere safe at home with the intention of using it again, then forgetting to take it with us next time we go to the shops.
"But the more bags we take, the more plastic makes its way into our environment, blighting our high streets, spoiling our enjoyment of the countryside, and damaging our wildlife and marine environments.
"Simple changes to our shopping routines, such as taking our own bags with us or using more bags for life, can make a huge difference in reducing the amount of plastic in circulation meaning we can all enjoy a cleaner, healthier country."
In England, the number of single-use bags given out by major supermarkets reached more than 7.6 billion last year - the equivalent of 140 per person and 61,000 tonnes in total.
Chancellor George Osborne admitted that he was a user of single-use plastic bags, and suggested he would pay the 5p charge rather than change his habits.
Mr Osborne told Sky News: "I'm ashamed to admit I'm a plastic bag user, and I'm glad I've had this opportunity to make that confession on your programme. But now I will be charged for it."