Zcash developers have chosen block 3,543,405 as the proposed activation height for the NU7 network upgrade, targeting a mainnet launch around November 5, though the date remains provisional until required software changes are finalized. The proposal was submitted by developer Sean Bowe on October 20 and had received two approvals but had not yet entered the official deployment specification as of Wednesday morning.
Faster confirmations: NU7 reduces Zcash’s target block time from 75 seconds to 25 seconds, roughly tripling confirmation speed. An exchange requiring three confirmations could see deposit wait times fall from nearly four minutes to about 75 seconds, depending on network conditions and exchange policies. The upgrade has been running on public testnet since October 4 at block 4,465,026.
Sprout deadline: The upgrade disables legacy version 4 transactions, closing the original Sprout shielded pool. As of October 17, Sprout held about 22,309 ZEC — roughly $26 million and 0.13% of supply. Holders must move funds to supported addresses before activation; ZIP 259 leaves the mainnet reissuance height to be calculated once the activation height is fixed.
Fee change: NU7 introduces a Network Sustainability Mechanism under which 60% of transaction fees are withheld from circulation when miners create blocks and recorded for later release to miners around February 2031. The design preserves the existing four-year halving cycle and avoids raising ZEC’s maximum supply.
Market context: ZEC traded near $1,140 on October 19, about 29% below its late-September peak near $1,600 and roughly 30% lower over the month. Shielded transactions recently reached as much as 56% of network activity. Operators running non-compatible software may continue on old rules, making the activation height a key coordination point for exchanges, wallets, and node operators.
