Key facts
- EU financial supervisors have identified quantum computing as a systemic threat to blockchain security.
- A future quantum computer could derive a private key from an exposed public key to authorize transactions.
- Google Quantum AI estimates breaking 256-bit elliptic-curve cryptography may require fewer qubits than previously thought.
- Ethereum aims for a quantum-resistant Layer 1 by December 2029.
- The Bitcoin Security Consortium is prioritizing quantum risk.
- France will stop certifying non-quantum-resistant products from 2027.
European Union financial supervisors have issued a warning that advancements in quantum computing pose a potential threat to the cryptography securing blockchains. The joint risk update from the European Banking Authority, European Insurance and Occupational Pensions Authority, and European Securities and Markets Authority highlighted that a powerful quantum computer could compromise systems used for transactions, communications, and databases by deriving private keys from exposed public keys. This concern is amplified by recent assessments from Google Quantum AI, whose researchers estimated in March 2026 that breaking the 256-bit elliptic-curve cryptography, the standard behind Bitcoin and Ethereum signatures, may require significantly fewer physical qubits than previously projected. While no such machine exists today, regulators are noting the direction of technological progress. In response, institutions are beginning to prepare for post-quantum migration. Coinbase is developing quantum-resistant custody solutions for institutional assets, and the Ethereum Foundation aims to achieve quantum resistance across its layers by December 2029. The Bitcoin Security Consortium, backed by major firms, has also prioritized quantum risk. El Salvador has taken immediate steps by splitting its Bitcoin reserve to cap individual wallet sizes and reduce quantum exposure, while XRP is targeting a quantum-ready ledger by 2028. The US is also moving in parallel with executive orders pushing federal migration targets toward 2030-2031, and France's ANSSI will cease certifying non-quantum-resistant products from 2027.