More than 140 MPs have added their signatures to an Early Day Motion calling for the banking and retail sectors to allow their customers to raise money for charity by offering the option of rounding up credit and debit card transactions to the nearest £1 through their PIN terminals.
It is thought that as much as £100m a year could be raised at the point of sale through the Pennies4change scheme.
The MPs also believe that the scheme could encourage "a culture of giving, resulting in a significant impact for those in need, and for good causes everywhere".
Retailers have also given the scheme a thumbs-up. Surrey independent Dean Holborn said: "We already collect large sums of cash in our charity box which is next to the till, so I think that a charity scheme for debit and credit cards would be just as popular.
"There is a possibility that it could make transaction times a little slower, but I don't think shoppers would mind that," he said.