Zcash’s NU7 network upgrade activated on the mainnet at block height 3,543,405 in early November. The upgrade reduces the target block interval from 75 seconds to 25 seconds and modifies the handling of transaction fees.
Faster target block interval
The new target aims to produce a block roughly every 25 seconds, compared with the previous 75‑second target. While the statistical target is shorter, actual block times remain variable, and exchanges or payment processors continue to set their own confirmation policies.
Impact on block rewards
To avoid a proportional increase in new coin issuance, the upgrade scales the scheduled reward per block and adjusts remaining issuance and halving intervals. This maintains the overall monetary issuance schedule while allowing more frequent blocks.
Network Sustainability Mechanism
NU7 introduces a fee reserve that directs 60% of transaction fees into a public reserve for future reissuance to miners, with the remaining 40% paid to miners at the time of collection. The mechanism is intended to smooth the decline in subsidy‑funded security as the network matures.
Node and wallet compatibility
Node operators must upgrade to a NU7‑compatible client, such as the Zebra 7 release, to stay on the consensus chain. Outdated node software may cause compatibility issues for wallets and services that rely on the network.
Other protocol changes
The upgrade retires support for older version‑four transactions associated with Zcash’s original Sprout pool, reflecting ongoing evolution of privacy features and proof systems.
Next steps for users and operators
Stakeholders should verify that their node software is updated, monitor observed block times, and check whether wallets and exchanges have announced NU7 support. The practical effects of the upgrade will become clear through network reliability and adoption of shielded transactions.
