Bitcoin Secures First Quantum-Resistant Transaction on Mainnet
On August 26, 2026, a significant milestone was reached in the world of cryptocurrency as StarkWare's Avihu Levy mined the first quantum-resistant Bitcoin transaction on mainnet using hash-based cryptography. This breakthrough is seen as a major step forward in securing the Bitcoin network from potential attacks by powerful quantum computers.
The problem with current public-key cryptography, used to secure most transactions, is that it can be broken by a sufficiently powerful quantum computer running Shor's algorithm. This threat has been estimated to be more than a decade away, but some experts, including Coinbase's research, believe preparation must begin now as protocol migrations take years.
The Quantum-Resistant Bitcoin (QSB) solution adds a second, hash-based lock alongside the usual elliptic-curve signature. Hash functions resist quantum attacks differently and provide approximately 118 bits of quantum-resistant security without requiring new opcodes or consensus changes.
The first QSB transaction was confirmed in block 964,199, mined by MARA Pool, with a transaction ID of 305a24ff…ab07. The output size was 10,000 satoshis, submitted via MARA's Slipstream because it is non-standard, and the computation cost was roughly $75, $150 in GPU time per transaction.