Quantum computing is a long-term migration problem for blockchains, not a present-day wallet emergency. Ethereum's security roadmap says no quantum computer available today can break its cryptography, and users do not need to take any action now. The concern is that a sufficiently powerful future machine could derive private keys from exposed public keys, allowing forged signatures and theft.
That possibility matters because blockchains cannot swap their cryptography overnight. Wallets, validators, exchanges, custody systems and consensus rules all depend on digital signatures. Changing those pieces without locking out users or splitting a network takes years of research, testing and coordination.
Ethereum is treating the transition as a stack-wide project
The Ethereum Foundation formed a dedicated post-quantum security team in January 2026. Its roadmap says weekly interoperability development networks are already running with more than 10 client teams, while core infrastructure milestones target roughly 2029. Ethereum stresses that those dates are planning targets and may move.
The work spans several layers. Account abstraction could let individual wallets choose quantum-safe signature verification without waiting for every user to migrate at once. Validator authentication would need a separate replacement for Ethereum's current BLS signatures, and data availability also needs post-quantum protection. The Foundation describes full protection as a coordinated, multi-layer transition rather than a single upgrade.
NEAR shows the difference between safer accounts and a safer protocol
NEAR says it added support for ML-DSA signatures for accounts in 2026. ML-DSA is a NIST standard for digital signatures that the agency says are designed to remain secure even against an adversary with a large-scale quantum computer.
That account-level support is meaningful, but NEAR's own roadmap makes clear that the network is not fully quantum-secure. The protocol still needs a post-quantum design for validators and block production. NEAR says the signatures it supports for accounts are currently too large and computationally expensive for consensus, which uses signatures far more frequently.
This distinction is easy to lose in a list of project milestones. A wallet that can rotate to a new signing scheme solves one part of the problem. Protecting an entire blockchain also requires compatible validator signatures, network performance, cross-chain support and a migration path for users who never update.
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