Zcash is preparing the testnet activation of its next network upgrade, a change that touches nearly every layer of the network at once. The upgrade, labeled NU7, is scheduled for testnet activation around October 6 and a mainnet launch on November 5. The design cuts Zcash’s block time from 75 seconds to 25 seconds, disables legacy v4 transaction handling, and introduces a Network Sustainability Mechanism intended to give the project a steadier funding stream once the current dev fund windfall runs down.
The upgrade has been in the works for most of the year. In September, holders approved a proposal to move to faster blocks while keeping the existing halving schedule intact, a pairing that has been contested inside the ecosystem for months. Sean Bowe, a Zcash core engineer, said at the time that the ecosystem engineering teams including Zcash Foundation, Project Tachyon, Valar Group, ZODL and Shielded Labs had agreed on scope and timeline. Deliverables were due September 30, after which the code would go to testnet for roughly two weeks of observation before a final mainnet activation height is locked in.
| Item | Schedule |
|---|---|
| Testnet activation | Around October 6 |
| Testnet observation window | About two weeks |
| Mainnet activation | November 5 |
| New block time | 25 seconds, down from 75 |
Why the block time is going down
Cutting the block interval requires changes across wallets, consensus code and network plumbing. Zcash’s current 75-second block schedule dates back nearly a decade, and it has made shielded wallet syncing slow and tedious. Developers estimate the bandwidth needed for a worst-case shielded wallet initial sync drops from 271 megabytes per day to about 169 megabytes under the faster schedule, though the full node work per unit of time goes up because more blocks have to be processed in the same window. That trade is the whole reason the change took a year: the protocol needs to move faster in a way both light clients and full nodes tolerate.
Version 4 transaction handling, a pre-Sapling format still accepted but increasingly rare, is disabled in the upgrade. The move removes attack surface and shrinks the base code the team has to keep patched going forward.
Sustainability, not just speed
The Network Sustainability Mechanism is the more political piece. Zcash’s existing development fund came from issuance set aside after the 2020 halving, and that source runs down over the next few years. The new mechanism redirects a slice of transaction activity into a standing pool, designed to fund core engineering and grants without going back to miners or founders for the money. Holders voted on the mechanism as part of the wider September package, and the result was accepted by a wide margin.
The vote itself was a test of how decentralized governance works in practice. Faster blocks mean more frequent reward events but smaller rewards per block, a trade miners watch closely because it affects cash flow. The halving schedule was kept intact, despite arguments that a faster chain effectively pulls future halvings closer, something the Foundation disputed on the grounds that total issuance per year does not change under the plan.
Separately, the Pretty Good Policy for Zcash group, a lobbying effort created earlier this month with a $750,000 grant, registered as a federal lobbyist on October 1 to push the stalled CLARITY Act and related crypto policy in Washington. Zcash has spent much of 2026 dealing with the fallout of delisting pressure from exchanges that treat privacy coins as regulatory risk, and the new lobbying push gives the project a political voice it has never had before. The Zcash group joins a small list of crypto policy shops active inside the Beltway, funded by industry players rather than a single token treasury.
Market context
Zcash traded near $551 on Monday, up 2.3 percent in 24 hours, leaving it far below the roughly $1,200 peak it reached earlier in the year when institutional interest in privacy was a live discussion topic. Because the token moves mostly with market sentiment rather than with technical milestones, the NU7 rollout is unlikely to shift price by itself. Still, a mainnet launch in November lands at a moment when the project’s narrative has cooled and traders are watching whether a faster chain and a sustainable funding pool can bring some of that interest back.
Engineers will not commit to a mainnet activation height until testnet holds up under load. Signaling code still needs to go live, miners have to upgrade, and wallets will adjust their sync logic. The two weeks between testnet and mainnet is when the remaining bugs usually show up. The plan assumes the ecosystem’s dev teams stay on schedule. If they do, Zcash enters November with quicker blocks, less legacy code, and a financing pool that does not depend on the halving clock running out.
What to watch next: whether the two-week testnet window holds on schedule, whether miners upgrade in time, and whether the Foundation publishes the final mainnet activation height at least a week before November 5, giving wallets and node operators real time to prepare. Past network upgrades in the space have slipped by days when miners lag behind schedule, which is why the Foundation wants to bake slack into the timeline rather than set the exact block height too early.
The Foundation has also had to manage expectations on a second front. Some community members expected NU7 to include a larger rework of shielded proof efficiency, work that slipped to a later upgrade. The Foundation has framed NU7 as a step toward a faster chain first, with deeper protocol changes coming after the block time change settles. That sequencing matters because a failed block-time change would cast doubt on the rest of the roadmap, while a successful one clears the way for the harder work later.