How to Protect Crypto Holdings from Quantum Computing Threats

Trezor shipped what it calls the “world's first quantum-ready hardware wallet” in April 2026, marketing the Safe 7 as a device built to protect crypto quantum computing threats cannot yet exploit but one day will. The launch arrived weeks after Google Quantum AI and the California Institute of Technology published updated estimates on when elliptic-curve cryptography might fall, placing the threshold between 2,500 and 10,000 logical qubits. Crypto holders do not need to wait for hardware manufacturers or protocol upgrades to act. Several defensive measures are available today.

Unexposed public keys remain shielded by hash functions

The single most important concept for quantum defense is public key exposure. Bitcoin addresses that have never sent an outgoing transaction keep their public key hidden behind two hash functions: SHA-256 and RIPEMD-160. Ethereum addresses use Keccak-256 for the same purpose. Solana follows a similar pattern with its Ed25519 scheme. No known quantum algorithm can efficiently invert these hash functions.

An address becomes vulnerable the moment it signs a transaction. Signing reveals the public key on-chain, and a quantum computer running Shor's algorithm could then derive the private key from that public key. “The math is binary,” said Emin Gün Sirer, founder and CEO of Ava Labs. “If the public key is on-chain, the address is exposed. If it is not, the address is protected by hash security that quantum computers do not threaten.”

On-chain analysis from Deloitte's 2025 quantum risk study estimated that 25% of all circulating Bitcoin sits in addresses with exposed public keys. For Ethereum, the figure is higher because the network's account model reuses addresses by default. Solana falls somewhere between the two.

Fresh addresses reduce quantum exposure immediately

Moving funds to a new address that has never made an outgoing transaction re-hides the public key. The process costs one transaction fee and takes minutes on any chain. Bitcoin users should generate a fresh receiving address for every incoming payment, a practice most modern wallets support automatically. Ethereum and Solana users can create new accounts and transfer balances in a single transaction.

Olaoluwa Osuntokun, chief technology officer at Lightning Labs, built a prototype quantum-resistant wallet rescue tool in early 2026 designed to automate this migration for Bitcoin holders with large numbers of exposed addresses. The tool scans a wallet's UTXO set, identifies addresses with on-chain public keys, and generates sweep transactions to fresh P2TR (Pay-to-Taproot) addresses. Osuntokun shared the prototype on GitHub in February but stressed it was “experimental and not for production use.”

Taproot addresses, which begin with “bc1p,” offer a structural advantage. P2TR uses Schnorr signatures combined with a tweaked public key construction that keeps the internal key hidden during standard spending. While Schnorr signatures remain quantum-vulnerable at the algorithmic level, the key-hiding property adds a layer of defense that older address formats like P2PKH and P2SH do not provide.

BIP-360 and BIP-361 propose Bitcoin's quantum upgrade path

Two Bitcoin Improvement Proposals address the quantum threat directly. BIP-360 introduces Pay-to-Quantum-Resistant-Hash (P2QRH) addresses that replace elliptic-curve signatures with lattice-based schemes from the NIST post-quantum standards. BIP-361 goes further by proposing a sunset timeline for legacy signature types, effectively forcing migration before a quantum attack becomes feasible.

Neither proposal has reached consensus among Bitcoin Core developers. Pieter Wuille, a Bitcoin Core contributor and co-author of the Taproot upgrade, said in a January 2026 mailing list post that BIP-360 “introduces reasonable design choices” but warned against rushing a soft fork without extensive testing. Wuille pointed to the SegWit activation timeline as precedent, a process that took over two years from proposal to deployment.

BIP-361's legacy sunset provision is more contentious. An estimated 4 million Bitcoin sit in addresses created before 2012 using pay-to-public-key (P2PK) scripts, which expose the public key permanently regardless of spending activity. Forcing those coins into new address formats would require cooperation from holders who may have lost access to their keys entirely, including the estimated 1.1 million BTC attributed to Satoshi Nakamoto.

Account Abstraction gives Ethereum wallets upgrade flexibility

Ethereum's ERC-4337 Account Abstraction standard, which went live in March 2023, separates the signing logic from the account itself. A smart contract wallet using Account Abstraction can swap its signature verification module without changing its address. When post-quantum signature schemes become available on Ethereum, Account Abstraction wallets can migrate their signing logic in place.

Vitalik Buterin, co-founder of Ethereum, said in a March 2026 blog post that Account Abstraction “is Ethereum's natural escape hatch for the quantum transition” because it avoids the mass migration problem Bitcoin faces. Standard externally owned accounts (EOAs) on Ethereum will still need a protocol-level upgrade, but smart contract wallets can act independently.

Safe (formerly Gnosis Safe), the largest smart contract wallet provider by total value locked, holds over $100 billion in assets as of April 2026. Lukas Schor, co-founder of Safe, said the team is “actively evaluating CRYSTALS-Dilithium as a signature verification module” and expects a testnet deployment before year-end.

Trezor Safe 7 and the hardware wallet quantum race

Trezor's Safe 7, released in April 2026, includes firmware that can generate and store CRYSTALS-Dilithium key pairs alongside traditional elliptic-curve keys. The device does not yet sign blockchain transactions with those keys because no major chain accepts Dilithium signatures at the protocol level. Instead, Trezor positions the feature as forward-compatible, allowing holders to generate post-quantum keys now and activate them once networks upgrade.

Matej Zak, chief technology officer at Trezor, called the Safe 7 “a bridge device” in an April press briefing. “Holders generate their post-quantum identity today, on hardware they control, and sign with it the moment their chain is ready,” Zak said. Ledger, Trezor's primary competitor, has not announced a comparable feature.

Skeptics note that storing an unused key pair provides no protection against quantum attacks on existing addresses. Peter Todd, a Bitcoin Core developer and long-time cryptography researcher, said on X in April 2026 that marketing quantum readiness “before any chain actually supports it” amounts to “selling insurance against a fire that has not started, for a house that cannot yet install sprinklers.”

NIST standards set the cryptographic foundation through 2035

NIST finalized its first set of post-quantum cryptography standards in 2024, selecting CRYSTALS-Kyber for key encapsulation and CRYSTALS-Dilithium for digital signatures. Falcon, a lattice-based signature scheme that both Solana core teams have adopted, was also selected. NIST has set 2035 as the target date for full migration of federal cryptographic systems away from algorithms vulnerable to quantum attack.

Cloudflare, which handles a significant share of global internet traffic, has targeted 2029 for deploying post-quantum security across its entire infrastructure. Blockchain networks operate on their own timelines, but the cryptographic primitives they depend on come from the same standards bodies. “Blockchains do not exist in a cryptographic vacuum,” said Dustin Moody, leader of the NIST post-quantum cryptography project. “When the underlying math breaks, it breaks everywhere.”

Gautam Chhugani, analyst at Bernstein, estimated a 3-to-5-year transition window for major blockchains to adopt post-quantum signatures in a February 2026 report. Chhugani's report placed Bitcoin at the highest risk due to the $170 billion in exposed P2PK and reused addresses, while ranking Ethereum and Solana as better positioned because of their more flexible upgrade mechanisms.

Distributing holdings across multiple addresses limits exposure

Concentration creates risk. A single address holding a large balance becomes a high-value target for any future quantum attacker. Spreading funds across multiple fresh addresses means a quantum breach of one key compromises only a fraction of total holdings. Institutional custodians already follow this pattern for operational security reasons, and the quantum threat adds another argument for the practice.

Coinbase, in its February 2026 quantum preparedness paper, advised institutional clients to “treat address hygiene as a first line of defense” and recommended rotating cold storage addresses on a quarterly basis. The paper noted that address rotation costs are negligible compared to the value at stake, with Bitcoin transaction fees averaging $1.20 and Solana fees averaging $0.003 as of February 2026.

Monitoring upgrade timelines separates preparation from panic

Each major blockchain publishes its own post-quantum research and upgrade roadmap. Bitcoin has BIP-360 and BIP-361 in discussion. Ethereum has Vitalik Buterin's account abstraction path alongside a longer-term protocol-level proposal. Solana has Anza and Firedancer converging on Falcon. Tracking these timelines allows holders to act before forced migrations or emergency forks compress the window for orderly transfers.

“The worst outcome is a quantum capability announcement that catches a chain mid-upgrade,” said Matthew Green, professor of cryptography at Johns Hopkins University, in a March 2026 interview. Green recommended that holders follow chain-specific governance channels and treat any proposed signature upgrade with the same seriousness as a consensus rule change.

If post-quantum upgrades deploy on schedule across Bitcoin, Ethereum, and Solana while quantum hardware remains below the cryptographic relevance threshold, the transition will resemble past cryptographic migrations that happened without loss of funds. If quantum hardware advances faster than expected, holders who maintained address hygiene and moved to fresh addresses will have bought themselves the time that holders with exposed keys did not.

This is not financial advice. Information current as of May 1, 2026.