Bitcoin and Ethereum developers are accelerating work to protect their networks from a future quantum computer capable of breaking the cryptography that guards crypto wallets, just as Washington starts putting serious money behind the machines that could one day do it.
The U.S. Commerce Department on Tuesday finalized a CHIPS Act award worth up to $100 million each for Rigetti, D-Wave and Quantinuum, while taking minority stakes in the three quantum-computing companies. The money is aimed at scaling hardware, manufacturing and error-correction systems needed for larger, fault-tolerant machines.
It comes as Ethereum’s protocol team has set December 2029 as a self-imposed deadline for making the base layer quantum-resistant across execution, consensus and data, planning as if the so-called “Q-day” could arrive as early as 2030.
Bitcoin has no equivalent network-wide deadline, but work has accelerated this year around Bitcoin Improvement Proposal (BIP)-360, which proposes a post-quantum output type, and BIP-361, which lays out a phased migration away from today’s ECDSA and Schnorr signatures.
Bitcoin researchers and institutions have similarly discussed 2029 as the window by which a credible migration path needs to be in place.
Crypto’s quantum race and the machines both point to 2029. (Shaurya Malwa/CoinDesk)
However, none of that means a quantum computer capable of stealing bitcoin or ether is expected in 2029.
Google Quantum AI estimated earlier this year that attacking 256-bit elliptic-curve cryptography could require fewer than 1,200 error-corrected qubits, or the smallest unit of information in quantum computing.
IBM nevertheless plans to deliver Starling, a fault-tolerant machine capable of running 100 million gates on 200 logical qubits, in 2029. Quantinuum is targeting hundreds of logical qubits around the same period.
While those figures cannot be compared directly with Google’s attack estimate, they show why protocol developers don’t want to wait until a cryptographically relevant machine already exists.
The migration is especially awkward for Bitcoin, because millions of coins sit in addresses whose public keys are already exposed, including an estimated 1 million $BTC belonging to creator Satoshi Nakamoto. BIP-361 proposes eventually restricting legacy signatures after a migration period, a step that could strand coins belonging to users who fail to move them.
Ethereum faces a different coordination problem. Its foundation has a dedicated post-quantum team and a fixed target, but moving wallets, applications and users onto new signature schemes could continue beyond the base-layer upgrade.