European financial regulators have issued a warning regarding the potential threat posed by sophisticated quantum computers to the cryptographic systems that protect blockchain technology. They cautioned that this risk may arise even before the technology is commercially viable.
This alert from the Joint Committee of the European Supervisory Authorities (ESAs)—comprising the European Banking Authority (EBA), the European Securities and Markets Authority (ESMA), and the European Insurance and Occupational Pensions Authority (EIOPA)—adds urgency to an ongoing debate about whether to lock or unlock Bitcoin stored in older wallets. Should quantum computers become capable of breaking Bitcoin’s encryption, approximately 6.9 million Bitcoins, valued at around $586 billion, could be at risk, according to data from Cryptoquant.
The authorities stated, “Threats could materialize earlier than any viable commercial application,” in their Autumn 2026 Risk and Vulnerabilities report released on Wednesday. The report highlights that an advanced quantum computer “could compromise several widely used cryptography systems that secure communications, transactions, databases, and blockchains.”
While the report does not specify when quantum computing might become commercially effective, a recent study by IBM suggests that it could be realized in four years or less.