Bitcoin's Quantum-Resistance Proposals Remain in Draft Stage

Bitcoin (BTC) has no agreed quantum-resistant upgrade. BIP-360's proposed output design and the SHRINCS signature draft remain short of adoption as work continues on ways to protect the network's cryptography.

BIP-360, or Pay-to-Merkle-Root (P2MR), would introduce an output type without Taproot's key-path spend. The design aims to reduce the long-term exposure of public keys, but it does not add post-quantum signatures or prevent key recovery while a transaction awaits confirmation.

A SHRINCS Working Group representative, conduition, announced the first draft Aug. 26, 2026, at 5:38 p.m. ET (21:38 UTC). The draft specifies a 48-byte public key, stateful signatures ranging from 548 to 4,619 bytes and a 5,777-byte stateless signature.

The compact stateful method requires signers to track which signing states they have used and never reuse them. If that state is lost or uncertain, the draft directs signers to refuse stateful signing and use the stateless option; a formal security proof, comprehensive test vectors and an optimized implementation remain unfinished.

Most experts expect a cryptographically relevant quantum computer possibly in the 2030s, though estimates vary widely and current quantum computers cannot break the cryptography reviewed.

BIP-360 remains a draft, and deploying SHRINCS would require a separate proposal to change Bitcoin's consensus rules. No signature scheme or migration timetable has been adopted.