Experts point out the challenges of post-quantum security for Bitcoin - ForkLog

# Experts Point Out Post-Quantum Security Challenges for Bitcoin

June 22, U.S. President Donald Trump signed an executive order to accelerate the transition of federal systems to post-quantum cryptography. Experts supported the direction but warned: the problem for Bitcoin is more complex, as a decentralized network cannot be updated by government decree.

SandboxAQ's Vice President of Engineering and Lead Scientist Stefan Lehnhaeuser told Decrypt that predicting the exact date of a cryptographically significant quantum computer is difficult, but a range of three to ten years already seems plausible. He warned that migration to post-quantum cryptography will take years, and organizations are likely already behind schedule.

Project Eleven CEO Alex Prudden called the White House's revised timelines overdue. According to him, Project Eleven estimates a 10% chance of a cryptographically significant quantum computer appearing by 2030, and a 50% chance by 2033.

Quantum Industry Coalition Executive Director Paul Stimers noted that industry roadmaps are converging around the period 2028–2030. However, he warned that public estimates may not account for classified quantum programs in the U.S. and other countries.

What does this mean for Bitcoin

According to The Block, the executive orders could accelerate investments and development in quantum security, including for the blockchain industry. However, the documents themselves concern federal systems and contractors, not decentralized protocols.

The quantum threat relates to the fact that a sufficiently powerful quantum computer could break some of today’s cryptography. For Bitcoin, the key risk is not mining but signatures: if the public key is exposed, a future quantum computer could potentially recover it and sign transactions.

In March, BTQ Technologies launched the Bitcoin Quantum v0.3.0 testnet with the implementation of BIP-360. This proposal introduces a Pay-to-Merkle-Root output type, which aims to eliminate quantum-vulnerable key-path spends similar to Taproot.

BIP-360 is in the Bitcoin Improvement Proposals repository, but the repository states that publishing a BIP does not mean community consensus or readiness for adoption. It is a formal step in the discussion process, not an approved network update.

In April, developers proposed BIP-361. It describes a more stringent migration scenario: if owners refuse to switch to quantum-resistant addresses, coins on vulnerable addresses with exposed public keys could be locked under certain conditions. The proposal has sparked debate: supporters see it as a necessary protective measure, critics view it as a violation of sovereign control over coins.

Why migration may be difficult

Project Eleven published a report titled The Quantum Threat to Blockchains 2026 in May. The report states that Q-Day in the baseline scenario occurs in 2033. The optimistic scenario points to 2030, while the pessimistic one extends to 2042.

For Bitcoin, the problem is not only technical. Transition will require coordination among developers, miners, exchanges, custodians, wallets, and large holders. For a network where major changes have historically been slow and politically contentious, this presents a separate risk. Migration could affect signature sizes, consensus rules, wallets, exchange infrastructure, custody services, and user practices. Therefore, even with working prototypes, the path from proposal to activation could take years.

Other networks are moving faster

Unlike Bitcoin, some ecosystems are already publishing more centralized plans. In June, the Stellar Development Foundation released a document, and Algorand Foundation also published a roadmap, while Coinbase's council described scenarios for quantum migration of Bitcoin.

Kohaku project leader at Ethereum Foundation (EF) Nicolas Consigny proposed a concept for protecting accounts from quantum computer attacks. The solution called SPHINCS- allows securing wallets without hard forks.

Recall that in January, EF announced post-quantum security as one of its main strategic priorities and formed a dedicated team of developers.