Sygnum executive: Banks must start Ethereum quantum preparations by 2027

BitcoinWorld Sygnum executive: Banks must start Ethereum quantum preparations by 2027 Banks that want to be ready for Ethereum’s planned quantum-resistant upgrade should begin overhauling their custody systems by 2027, according to Thomas Brunner, head of custody and staking at Sygnum Bank.

The warning comes as Ethereum developers weigh a timeline that could see Layer 1 transition to quantum-resistant cryptography by 2029, although that date remains tentative.

Why the 2027 deadline matters Brunner highlighted that preparing for quantum-resistant signatures is not a simple software update. Future cryptographic methods will require strict controls, including a ban on reusing the same key.

This creates a direct conflict with current banking practices, where systems are often duplicated or rolled back to earlier states during backup and disaster recovery processes.