- Zcash developers have set block 3,543,405 as the target for the NU7 mainnet activation, anticipated around November.
- The NU7 upgrade will lower target block times from 75 down to 25 seconds, pull 60% of transaction fees out of circulation, and turn off legacy Sprout transactions.
The Zcash NU7 mainnet upgrade is aiming for activation at block 3,543,405—projected for roughly November 5—following the final adjustments to ZIP 259, as reported by the Zcash development group Zakura.
In an October 21 statement on X, Zakura noted that the activation height was locked in alongside the final tweaks to the deployment proposal. Furthermore, the team verified that its NU7 dashboard has been updated to show this scheduled activation point.
Several network alterations will arrive with the upgrade, such as accelerated block generation, modifications to transaction fees, and the retirement of the older Sprout transaction format.
Having successfully deployed to the Zcash testnet on October 4, NU7 allows developers to evaluate modifications ahead of the mainnet release. Keep in mind that the November 5 date is an approximation since activation relies on hitting the designated block height instead of a strict clock time.
NU7 to Cut Target Block Time to 25 Seconds
A central feature of the upgrade is shortening Zcash’s target block interval from 75 seconds down to 25 seconds. Consequently, blocks will be produced three times more often, which could help minimize delays in transaction confirmations. This adjustment does not guarantee a 25-second confirmation for every transaction, as actual speeds continue to rely on network activity.
Additionally, NU7 will launch the Network Sustainability Mechanism and extract 60% of transaction fees from active circulation. Based on the new rules, these fees will be stored for later issuance while maintaining the current halving schedule for Zcash. The planned return of these funds is scheduled to commence around February 2031.
Version 4 transactions, which are necessary for moving assets out of the legacy Sprout privacy pool, will also be deactivated by the upgrade. Consequently, any assets left inside Sprout following activation will be permanently unspendable under the updated consensus rules. Wallet holders with balances in that pool are advised to check their accounts and transfer any eligible assets before the network transitions.
While NU7 does not roll out a brand-new transaction format, full-node operators, indexers, and block explorers must ensure they run compatible software to remain synchronized with the upgraded network.
This November target window provides a tight schedule for exchanges, wallet services, and infrastructure maintainers to get ready for the consensus shift.
Frequently Asked Questions
When is the Zcash NU7 upgrade scheduled to activate?
The NU7 upgrade is targeting block 3,543,405, which is anticipated to occur around November 5. Because activation is tied to block height rather than a specific time, this date remains an estimate.
What are the main changes introduced in NU7?
NU7 reduces target block times from 75 to 25 seconds, introduces the Network Sustainability Mechanism to remove 60% of transaction fees from circulation, and disables version 4 legacy Sprout transactions.
What happens to funds left in the legacy Sprout pool?
Because NU7 disables version 4 transactions required for the Sprout privacy pool, any funds remaining in Sprout after activation will become unspendable. Users are advised to move eligible funds beforehand.
When will the fees removed by the Network Sustainability Mechanism be reintroduced?
The reintroduction of the funds held by the Network Sustainability Mechanism is expected to begin around February 2031.
