Wrap (Waste and Resources Action Programme) said 8.1 billion of the bags were used last year – up 1.3 per cent on 2011.
There was a 4.4 per cent increase in England but a 76 per cent decrease in Wales, where a 5p charge per bag was introduced in October 2011.
The average number of bags used per month by supermarket customers across the UK increased from 10.5 in 2011 to 10.7 in 2012.
The overall number of bags, including re-usable bags, issued by supermarkets in 2012 totalled 8.5 billion compared to 8.4 billion bags in 2011 – an increase of 1.1 per cent between 2011 and 2012.
However, Wrap said the number of single-use bags distributed in the UK had decreased by 34 per cent compared with 2006, when reporting began.
And it said a decrease in the average weight of bags meant the total weight of all those distributed fell by 2.6 per cent to 70,400 tonnes, a 36 per cent decrease since 2006.
It also found that around 60 per cent of supermarkets have front-of-store recycling points for customers.
Data on carrier bags issued by supermarkets has been gathered and analysed by Wrap at the request of UK governments since 2006.
The British Retail Consortium (BRC) said the increase reflected changing shopping trends and “shouldn’t detract from areas where excellent progress has been made”.
It said consumers were increasingly using “top-up shopping” in addition to larger weekly shops, but typically using smaller and lighter bags to do so.
BRC director of food and sustainability, Andrew Opie, said: “Bag usage may not have fallen, but that doesn’t mean that supermarkets’ progress has stalled on addressing this and wider environmental issues.”
The Campaign to Protect Rural England, which is a member of the Break the Bag Habit campaign, said there were “no credible reasons left” for the Government not to introduce a charge on all carrier bags in England.