A new Bitcoin Improvement Proposal (BIP) aims to reduce the threat posed by quantum computers by replacing the Bitcoin’s legacy signature schemes, which can be vulnerable to quantum attacks, with quantum-resistant alternatives. The proposal, titled “Post Quantum Migration and Legacy Signature Sunset,” was drafted by a group of cryptography and blockchain experts, including American software engineer Jameson Lopp and BitcoinQS founder Christian Papathanasiou. While quantum computers powerful enough to crack Bitcoin’s cryptography are not yet on the market, recent developments have narrowed the window for their launch. Some academic forecasts suggest quantum machines capable of threatening Bitcoin could arrive as early as 2027 to 2030. Bitcoin currently relies on ECDSA and Schnorr signatures to secure transactions. Still, around a quarter of all Bitcoin’s unspent outputs have already revealed public keys onchain, making those funds particularly vulnerable to a quantum attack. A successful quantum attack on Bitcoin would result in significant economic disruption and damage across the entire ecosystem. Beyond its impact on price, the ability of miners to provide network security may be significantly impacted.

The proposal suggests a phased approach to address the risks posed by quantum computers. The first phase suggests stopping people from sending Bitcoin to older, less secure addresses that quantum computers could easily break. Around five years after this change, the plan will go further by making it impossible to spend any Bitcoin stored in those old, vulnerable addresses, essentially freezing these coins. There is also a possible future step being studied, which might allow people to recover their frozen Bitcoin by proving ownership with special cryptographic methods linked to their wallet’s backup phrase, but this part depends on further research and demand. The authors wrote that the longer we postpone migration, the harder it becomes to coordinate the situation. They argue that a clear, time-boxed plan will create certainty, align stakeholders, and minimize the risk of catastrophic quantum theft. The recent advances like Microsoft’s Majorana chip have accelerated the development of powerful quantum computers, which operate differently from the classical machines. These quantum systems threaten Bitcoin’s core security algorithms, especially as about 30% of BTC coins sit in addresses vulnerable to quantum attacks. The real threat isn’t quantum technology itself, but the community’s delay in acting decisively to secure the Bitcoin’s future.