Coinbase Report Warns 7 Million Bitcoin Could Face Future Quantum Computing Risks

A new report from Coinbase’s Independent Advisory Board on Quantum Computing and Blockchain estimates that around 7 million Bitcoin could be vulnerable to future quantum computing attacks. While no existing quantum computer can break Bitcoin’s cryptography today, researchers say preparations should begin now because a network-wide transition could take years.

The report divides the risk into two categories. About 1.7 million BTC are held in roughly 20,000 legacy Pay-to-Public-Key (P2PK) addresses, where public keys are openly visible on the blockchain. Many of these coins are believed to belong to early users, including wallets linked to Bitcoin’s creator, Satoshi Nakamoto.

Address Reuse Creates Larger Exposure

The bigger concern involves approximately 5 million BTC tied to address reuse. According to the report, these coins belong largely to active users and include cold wallets controlled by major cryptocurrency exchanges and institutions. Once a public key is exposed through address reuse, it could become vulnerable if powerful quantum computers emerge.

Bitcoin Community Faces Governance Debate

The report outlines several possible solutions, including freezing vulnerable coins after a migration deadline, adopting post-quantum security upgrades, implementing the Hourglass model, using BIP-361, or deploying Provable Address-Control Timestamps (PACTs).

The advisory board did not endorse a specific approach but urged developers to begin post quantum migration work immediately and improve communication with users. The board emphasized that although the threat remains theoretical today, delaying preparations could leave the Bitcoin network unprepared in the future.