Retail groups have welcomed a probe into retail banking by the European Commission, which has highlighted problems over payment cards.
The Commission's inquiry revealed a number of concerns, including large variations in merchant fees.
The British Retail Consortium said it was pleased excessive charges had been recognised and said the EU had sent a clear signal that retailers are bearing the costs of banks abusing their position.
Londis retailer David Brunt from Stoke-on-Trent said: "My charges are horrendous and that's despite me pretty much getting as good a deal as I can through Londis. I'm paying more than £200 a month and have to pass on the charges to the customer, which doesn't look good."