The European payment system is currently facing its biggest challenge from a regulatory standpoint rather than a technical one, according to recent analyses. While Europe is working to develop its own payment infrastructure, it lacks a unified framework to determine accountability when things go wrong. The EuroPA alliance, through its European Payment Initiative (EPI) and the Wero wallet, has proposed a plan that could eventually link 380 million users across 15 European countries. This would be a significant technical step forward, but the issue of how different payment systems can work together seamlessly — known as interoperability — remains unresolved. Specifically, it is still unclear who would be held responsible if a payment chain fails at the European level. In the area of data protection, Europe has a well-established framework in the form of the General Data Protection Regulation (GDPR), which clearly defines who is responsible for hosting data and who controls access. This framework has been in place for years and now influences how companies structure their contracts with data hosts. However, for payment systems, there is no similar framework. A banking license or payment institution status determines who processes a transaction, but there is no overarching European regulation that defines who is responsible when a payment chain fails. Some experts argue that the infrastructure is being built, pointing to examples like Bizum, Bancomat, and MB WAY, which have enabled cross-border payments since March 2025. A successful test in April demonstrated that in-store payments can be processed across borders, with a full cross-border payment journey expected by 2027. While these are important developments, they do not address the issue of responsibility when payment chains fail or when two different networks shift responsibility for an incident onto each other. Christine Lagarde, in a speech at the Bundesbank in January, highlighted that the digital euro offers a chance to strengthen Europe’s independence and resilience in financial matters. However, she noted that these opportunities are not automatic — they must be built through deliberate decisions, not just by connecting more technical systems. The issue of determining responsibility in payment failures is not new; when card payments became widespread, payment networks spent years defining who would bear the cost of fraud or disputes. These efforts eventually led to clear rules, such as deadlines for disputes and how refunds are shared between issuing and acquiring banks. However, no similar framework exists for the new instant and cross-border payment systems being developed in Europe today. For a French company that processes transactions using multiple payment systems, the lack of a clear regulatory framework is not just a theoretical concern. If an incident occurs on a cross-border payment chain, it is unclear which regulations would apply or which authority would make a ruling in case of a dispute. This uncertainty increases the cost of internal arbitration, complicates compliance audits, and places a burden on each company that only a common regulatory framework could resolve. The technical development of the payment system is moving forward, which is a positive sign. However, as long as the regulatory framework for accountability does not keep pace, each new interconnection will add capacity without providing any real guarantees. The priority for European authorities and payment providers is no longer to expand the number of payment systems but to create clear rules — through supporting documents — that determine who is responsible when one of these systems fails.