Zcash upgrade reduces block time from 75 to 25 seconds and modifies post-2031 security funding mechanism.
Tech & Launches ·
Zcash developers plan to activate NU7 on November 5, an upgrade that would reduce block confirmation time from 75 seconds to 25 seconds—a threefold acceleration for transactions using the network's zero-knowledge privacy layer. The improvement aims to bring shielded payment settlement speeds closer to traditional card processing. Five development organizations including the Zcash Foundation and Shielded Labs have aligned on the upgrade's scope, with testnet deployment targeted for October 6 and mainnet activation height finalized October 20.
To prevent the faster block cadence from tripling daily token issuance, NU7 reduces per-block rewards proportionally through a proposal called ZIP 218, keeping total ZEC creation per unit of time unchanged. This preserves Zcash's Bitcoin-style halving schedule, which 98.9% of voting coinholders chose to retain in a direct ballot covering 2.4 million ZEC from 66% of eligible participants. The upgrade introduces no new transaction types and requires no wallet modifications for ordinary users.
The upgrade's longer-term consequence is the Network Sustainability Mechanism, which will begin reserving roughly 60% of transaction fees starting in 2026. These accumulated fees will convert to supplemental miner rewards beginning February 2031, addressing revenue shortfalls after halvings approach zero while maintaining the fixed-supply commitment central to Zcash's design. The mechanism's February 2031 start date reflects what developers described as the most conservative interpretation of the coinholder vote.