Zcash activated its landmark Network Upgrade 7 (NU7) early Friday, cutting the target time between blocks from 75 seconds down to 25 seconds and enabling private transactions to confirm up to three times faster across the network. The milestone upgrade went live at block 3,543,405, mined at 02:34 UTC, and produced 225 blocks by 04:59 UTC as mining difficulty began adjusting toward the accelerated block pace.
The reduction in block intervals is designed to significantly improve real-world usability for privacy-focused payments across merchants and cryptocurrency exchanges. Under the new standard, a merchant can see an initial transaction confirmation in approximately 25 seconds on average, while services such as exchanges requiring three block confirmations can see expected waiting times drop from nearly four minutes down to roughly 75 seconds. Actual payment availability will continue to depend on the specific confirmation requirements set by individual service providers.
Engineers at Valar Group and Project Tachyon prepared the network for 25-second blocks using Zakura node software, testing high transaction loads across 80 computers in 11 regions. To prevent discarded block rates from surging during shorter intervals, developers optimized transaction validation by caching initial check results. NU7 also introduces per-block caps on private transaction activity, reducing the worst-case daily scanning download burden for mobile wallets from 271 megabytes to 169 megabytes while more than doubling network capacity for simple shielded payments from roughly three to over six transactions per second.
The upgrade also restructures Zcash transaction fees and network rules, directing 40% of fees to active miners while placing the remaining 60% into a reserve to supplement block rewards starting around February 2031, preserving the 21 million coin supply cap. Additionally, NU7 officially retired Sprout, Zcash’s original 2016 privacy pool, leaving approximately 12,224 ZEC unspendable pending any future consensus-approved recovery mechanism.
