Zcash Activates NU7 Upgrade on Testnet
Zcash has launched its NU7 network upgrade on the public testnet, introducing faster block times and a new fee-recycling mechanism ahead of a potential mainnet rollout.
Zcash has officially activated the NU7 network upgrade on its public testnet at block height 4,465,026. This deployment marks the first time the protocol overhaul is live in a testing environment, utilizing the Zebra 7.0.0-rc.0 node software.
The upgrade introduces several technical changes, most notably a reduction in target block times from 75 seconds to 25 seconds. Additionally, the update implements a Network Sustainability Mechanism, which is designed to direct 60% of transaction fees toward supporting the network. The upgrade also includes the retirement of the Sprout shielded pool, effectively disabling v4 transactions.
The development of NU7 involved collaboration between the Zcash Foundation, Project Tachyon, Valar Group, ZODL, and Shielded Labs. These organizations reached a unanimous agreement on the scope of the upgrade following a poll of coinholders.
While the testnet is now active, mainnet operators are not required to take action yet, as no activation height has been set for the mainnet. A decision regarding the mainnet rollout is scheduled for October 20, 2026, with a target activation date of November 5, 2026.
Infrastructure providers, including node operators, exchanges, and wallet services, face a tight timeline to ensure compatibility. Any software currently relying on the Sprout shielded pool or v4 transactions will require updates before the mainnet activation occurs.
