Visa and Mastercard are facing a potential £5bn legal challenge in the UK over the fees they charge businesses for processing card payments. Two law firms, Harcus Parker and Hausfeld, have submitted an application to the Competition Appeal Tribunal to launch a collective action lawsuit. The case centers on 'multilateral interchange fees,' which are set by the card networks and paid by merchants through their banks whenever a customer uses a card for a purchase.

The legal teams argue that these fees are excessive and have stifled competition, effectively acting as a hidden tax on businesses. The proposed claim aims to recover damages for UK companies that have been subject to these charges since October 2020. While the application has been lodged, it must still be certified by the tribunal before the lawsuit can proceed as a group claim. Neither Visa nor Mastercard has provided a detailed defense in the public record yet, though both companies have historically maintained that their fee structures are transparent and compliant with regulatory standards in the markets where they operate.