A draft Solana protocol proposal would end durable nonce transactions no earlier than May 5, 2027, requiring custodians and other users of offline signing to adapt how they prepare and submit transactions.
SIMD-0723, published Nov. 5, would require transactions to use a recent blockhash. Under the proposal, a transaction signed with a nonce could no longer remain usable after its blockhash window expires. The proposal would leave users able to withdraw funds from nonce accounts or change their authorities, but would prevent creating, advancing or upgrading those accounts.
Solana’s transaction documentation says a recent blockhash is valid for 150 slots and describes durable nonces as a way to support offline signing and later submission. The proposal says custodians, exchanges and other workflows that submit transactions after that window would need to migrate. Those users would bear the work of changing processes that depend on delayed submission.
The proposal’s stated rationale is to reduce special-case validation and replay rules across validator clients. It links those rules to security vulnerabilities and consensus bugs. The change would leave transactions using the usual recent-blockhash method for replay protection.
Solana’s June 2022 postmortem attributed the block-production stoppage, which lasted about four and a half hours, to a runtime bug that allowed a failed durable-nonce transaction to be processed a second time.
The proposal lists Programmatic Signer and Blueshift Vector as examples of programs that could support offline and delayed signing. SIMD-0723 remains labeled Draft and names no scheduled decision date. May 5, 2027, is the earliest proposed mainnet-beta activation date, not a confirmed launch date.
