Zcash Activates NU7 With 25-Second Block Target and New Fee Reserve

TL;DR: Zcash’s NU7 upgrade activated at mainnet block 3,543,405, reducing target block spacing from 75 to 25 seconds. It also changes how fees contribute to future network security. Faster target blocks do not make every payment final instantly, and node operators need compatible software. Zcash has crossed an important protocol milestone. The NU7 network upgrade activated in early November at block height 3,543,405, bringing a faster target block interval and changes to the economics of future block rewards. The Zcash Foundation’s Zebra 7 release notes identify the same mainnet activation height and describe the consensus changes required for nodes to follow the chain. The upgrade is not just a software patch. It changes how Zcash produces blocks and how some transaction fees are handled, while preserving the wider coin-issuance framework. What moving from 75 to 25 seconds changes Zcash’s new target is a block every 25 seconds, down from 75 seconds before the upgrade. In theory, that means users and services waiting for several confirmations can receive them sooner. But target spacing is a statistical expectation, not a service-level guarantee: real blocks arrive irregularly, and ...