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- Zcash has activated its NU7 network upgrade on public testnet with a targeted Nov. 5 mainnet rollout.
- The upgrade reduces target block spacing from 75 to 25 seconds and allocates 60% of transaction fees to a mining reserve.
- Developers plan to review testnet performance on Oct. 20 before deciding whether to proceed with mainnet activation.
Zcash has activated its NU7 network upgrade on public testnet, putting 25-second blocks and a new transaction fee mechanism into live testing ahead of a targeted Nov. 5 mainnet rollout.
The upgrade went live at testnet block 4,465,026 on Oct. 4, two days earlier than developers had expected. Node operators, wallets, exchanges and other infrastructure providers can now test the changes before developers make a final mainnet decision.
NU7 Cuts Block Target From 75 to 25 Seconds
NU7 reduces Zcash’s target block spacing from 75 seconds to 25 seconds, cutting the average wait for a first confirmation by two-thirds.
The faster schedule produces three times as many blocks over the same period, while per-block issuance is adjusted so the change does not increase Zcash’s 21 million ZEC maximum supply.
Developers expect shorter block times to improve payments, exchange deposits and cross-chain bridge processing.
NU7 Sends 60% Of Transaction Fees to Future Mining Reserve
The upgrade also introduces a Network Sustainability Mechanism that changes how transaction fees are distributed.
Miners will receive 40% of fees, while the remaining 60% will be removed from circulating supply and recorded in a consensus-tracked reserve.
Those funds are intended to support future mining rewards as scheduled ZEC issuance declines, with reissuance from the reserve planned to begin in 2031.
Sprout ZEC Must Move Before Mainnet Activation
NU7 disables version 4 transactions, which are required to spend funds held in Zcash’s legacy Sprout shielded pool.
Any ZEC left in Sprout when NU7 activates on mainnet would become unspendable through the existing transaction system. Version 5 and version 6 transactions remain supported.
The change makes migration necessary for any remaining Sprout holders before mainnet activation.
Developers Face October 20 Decision On November 5 Rollout
Zcash developers plan to review testnet performance on Oct. 20 before deciding whether to proceed with mainnet activation and setting an activation block height.
Nov. 5 remains a target rather than a confirmed launch date. Mainnet operators have not yet been instructed to upgrade while developers monitor NU7’s testnet performance.
