Zcash (ZEC) NU7 Upgrade Guide: Key Changes Beyond Faster Blocks

 

Zcash's NU7 network upgrade sits at an unusual stage: the testnet has been running for two weeks, the mainnet target date is November 5, and the activation height has not been set. The official Zcash upgrade page currently states that the activation height for NU7 has not yet been set, and the Zcash Foundation's release notes for Zebra 7.0.0-rc.0 likewise state that no mainnet activation height has been set and that mainnet operators need take no action yet.

 

That distinction matters for users. Zcash upgrades activate at a block height rather than triggering on a calendar date, so November 5 is a plan rather than a commitment. Per the NU7 timeline developers published on the community forum, the final mainnet decision and height setting were scheduled for October 20, while Blockhead reported on October 21 that the decision was set for that day, to be settled by engineers from the core teams. At the time of writing no activation height has appeared on the official page.

 

NU7's main content shortens the target block interval from 75 seconds to 25 seconds while adjusting the issuance cadence, introducing a transaction fee reserve, and disabling legacy v4 transactions. That last change closes the Sprout shielded pool, which is the only part of this upgrade requiring specific users to take action themselves.

 

This guide labels each item by one of three states: changes already live on testnet, changes planned for mainnet, and information still unconfirmed.

 

 

 

The activation height has not been set. Both the official upgrade page and the Zebra release notes state that no mainnet activation height exists, making November 5 a target rather than a commitment.

 

The testnet has run for two weeks. NU7 activated on the public testnet at height 4,465,026, and per Blockhead it went live on October 4, slightly ahead of the published October 6 expectation.

 

The block interval drops to 25 seconds. Per ZIP 218, the target block interval falls from 75 seconds to 25 seconds, shortening average first confirmation to roughly 25 seconds.

 

Daily issuance stays the same. The per-block reward is divided by three while the halving interval extends from 1,680,000 blocks to 5,040,000, leaving the 21 million cap and the halving schedule unchanged.

 

Sixty percent of fees go to a reserve. Per ZIP 235 as described in the Zebra release notes, 60% of each block's transaction fees enter a reserve with miners keeping 40%, the reserve is reissued block by block under ZIP 237, and the arrangement to return fees to miners begins in February 2031.

 

The Sprout pool will close. Disabling v4 transactions closes the Sprout shielded pool, which held roughly 22,309 ZEC on October 17, so holders need to move funds before activation while the migration deadline depends on an activation height not yet set.

 

 

Separating the three states is a precondition for using this guide.

 

 

On governance, the post publishing the timeline states that unanimous agreement exists among the organisations and engineering teams, with participants including the Zcash Foundation, Project Tachyon, Valar, ZODL and Shielded Labs. A coinholder poll drew roughly 2.4 million ZEC, 66% of the eligible pool, of which 98.9% backed keeping the halving schedule and 96.6% chose February 2031 as the start date for returning fees to miners.

 

Worth emphasising is that every date in the forum post is a target, and the mainnet height was scheduled to be set on October 20 under the original plan. Blockhead noted that Zcash upgrades activate at a block height, so until that height is published any specific date should be read as an expectation rather than a settled fact, and a deferred decision would push the dates back as a set.

 

 

The effect of the block interval change is more specific than simply faster.

 

Per ZIP 218, the target block interval falls from 75 seconds to 25 seconds, roughly a third of the original, and average waiting time for a first confirmation falls to roughly 25 seconds accordingly. The Zebra release notes tell exchanges and indexers to expect first confirmations of roughly 25 seconds.

 

The practical value concentrates in situations requiring a fixed number of confirmations. Per CoinDesk's explanation, the three times faster framing refers to the time an exchange or bridge needs before releasing ZEC after waiting a fixed confirmation count falling to roughly a third, not to a threefold increase in the processing speed of an individual transaction. That report also notes a shop-counter payment would still be slower than tapping a card, while the shorter wait makes direct private payments more practical.

 

The shorter interval also comes with accompanying constraints. The Zebra release notes set per-block shielded limits of 330 Orchard or Ironwood actions, 300 Sapling inputs and outputs, a shared budget of 330 across pools, and no new Sprout JoinSplits, enforced by Zebra in both block template construction and mempool admission. Individual block capacity for shielded transactions is therefore explicitly bounded, and capacity expansion comes from the increased number of blocks.

 

Several engineering-level changes accompany this. The getblock call gains verbosity 3, which provides input prevout data and fees in one call for exchanges and indexers. The mainnet getstandardfee schedule is set at 5,000 zatoshis per logical action until height 3,590,000, then 1,000. A new 50-minute grace window avoids penalising peers that relay transactions built for adjacent upgrades.

 

 

This section is most often misread as either inflation or a supply cut, and it is neither.

 

On issuance, per ZIP 218 the per-block reward is divided by an additional factor of three while the halving interval extends from 1,680,000 blocks to 5,040,000, a tripling. The two adjustments offset, leaving the issuance rate per unit of wall-clock time unchanged, which the Zebra release notes express as daily ZEC issuance staying the same. The 21 million cap and the halving schedule are both unchanged. CoinDesk describes issuance over time as largely unchanged, since fewer coins per block are offset by more blocks and a longer halving interval.

 

The fee mechanism is the genuinely new element, called the Network Sustainability Mechanism. Per the Zebra release notes, ZIP 235 directs 60% of each block's transaction fees into a reserve with miners keeping 40%, while ZIP 237 has each block reissue a small, predictable portion of that reserve on top of its normal reward. Worth noting is that the forum's NU7 timeline lists this as ZIP-234 (alt) and ZIP-235, a different numbering from the implementing team's, so citations should specify the source.

 

The practical effect removes part of the fees from circulation temporarily and returns them on a set schedule. CoinDesk describes roughly 60% of transaction fees being temporarily removed from circulation rather than going to miners, with those coins scheduled to return through block rewards starting February 2031. Coinholders chose that February 2031 start date with 96.6% support, so the date rests on an explicit governance basis.

 

The direct effect on miners warrants separate statement. The Zebra release notes tell miners and pools that coinbases claim only the 40% fee share, and that getblocktemplate lists only the time field as mutable, so a new template should be requested rather than an existing one edited. Miner fee income therefore declines under the new rules before February 2031, and that reduction is an arrangement fixed by a governance vote rather than a temporary parameter.

 

 

The required action differs sharply by role, and mixing them together leaves ordinary holders over-anxious or node operators under-prepared.

 

 

The vast majority need do nothing. The forum timeline describes the ecosystem impact as wallets being largely unaffected, while the Zebra release notes tell wallets to expect faster confirmations and new per-block shielded limits and to adopt the lower mainnet fee schedule as it applies. The sole exception is anyone holding assets in the Sprout pool, covered in the next section.

 

 

This is the group that must act. The official upgrade page states plainly that if NU7 includes major consensus changes, as the page expects, zcashd will not support it, and operators need to switch to Zebra, the Zcash Foundation's consensus node, with upgrade guidance in the Zebra Book.

 

Testnet operators specifically must upgrade before height 4,465,026. If a configuration pins public testnet consensus values via network.testnet_parameters, those overrides must be removed or Zebra will refuse to start on public testnet. Custom testnet and Regtest operators must resync after upgrading, and configurations are now validated at startup.

 

Also note the warning in ZIP 259 that operators not running compatible software may stay online under the old rules, meaning the consequence of not upgrading is not a halted node but one running out of consensus with the network.

 

 

ASIC miners themselves need take no action. The official upgrade page explains that ASIC miners do not verify consensus rules and NU7 likely will not change the block header, so miners depend on their pool upgrading its nodes. Pools must handle the 40% fee share and the template request change noted above, and testnet mining requires a synced node.

 

 

Exchanges and indexers should expect first confirmations of roughly 25 seconds and can use verbosity 3 to obtain input prevout data and fees in a single call. Wallet and infrastructure developers face larger changes, as the state database moves to format v29, Zallet's and Zaino's Zebra backends must use v29-compatible builds matching the node, library users should expect breaking API changes, and the v28 to v29 migration is automatic and one-way, so the v28 state should be backed up first. For the basics of wallet selection and asset management, see our Zcash wallet guide.

 

 

This is the only part of the upgrade requiring specific users to act before a deadline, and it concentrates the risk.

 

NU7 disables legacy v4 transactions, and the direct consequence is closing the Sprout shielded pool. Per Blockhead's reporting, the Sprout pool held roughly 22,309 ZEC on October 17, around $26 million, or 0.13% of supply. Holders retain their own keys but cannot spend those assets normally on the upgraded network unless they move them beforehand. Coinholders backed this cutoff in an earlier vote.

 

The timing problem is that the deadline itself is undetermined. Blockhead notes that the mainnet reissuance height depends on the activation height, so the deadline for moving Sprout funds is not yet fixed, while exchanges and custodians holding Sprout-era coins want confirmed migration plans before the height is set.

 

Community forum discussion adds a further layer whose nature needs flagging. Forum replies, which are not official announcements, state that Sprout funds will not be spendable normally after November 5 and that recovery would require some other mechanism, with a related thread discussing a possible future Sprout redemption mechanism. These are community discussions rather than official commitments and should not be treated as a basis for action.

 

For users holding Sprout assets, the prudent approach is therefore not to wait for the deadline to be announced but to complete the transfer before the activation height is fixed. For exchanges and custodians, the task is confirming whether they hold Sprout-era assets and planning around the official migration guidance once published.

 

 

NU7 and Tachyon get discussed together often, yet they are different in kind.

 

NU7 changes parameters and consensus rules: block interval, issuance distribution, where fees flow, and the retirement of a legacy transaction format. It introduces no new transaction formats, so ZSAs fall outside this upgrade, with forum replies describing their status as still under debate. Tachyon is a separate architectural path aimed at scaling shielded payments and is not part of NU7, with its design covered in our explanation of the Zcash Tachyon upgrade. Worth noting is that Project Tachyon is among the teams that reached consensus on the NU7 timeline, so the two paths advance in parallel rather than substituting for each other.

 

Tracking confirmations should rely on three sources. The first is the official upgrade page, which will update once an activation height is set and currently states that none exists. The second is the Zcash Foundation's release notes, where a stable Zebra release and mainnet guidance would be published, with the latest currently being release candidate 7.0.0-rc.0. The third is the NU7 timeline thread on the community forum, where developers maintain a progress checklist whose dates are targets.

 

Market expectations deserve sobriety. ZEC traded near $1,140 on October 19, roughly 29% below its late-September peak near $1,600, and per Coinbase's data the price has been near $1,138 with a 1.27% decline over twenty four hours, a market capitalisation around $19.39 billion and circulating supply around 17 million. An analysis cited by Blockhead noted the upgrade does not directly create token demand, so the decision matters more to node operators than to price. One on-chain change worth watching over the same period is shielded transactions reaching as much as 56% of activity, a level not seen in years.

 

Follow ZEC spot pricing on MEXC to track market moves around the upgrade, where the pair trades as ZEC against USDT

 

 

For James Mitchell, the most notable thing about this upgrade is not 25-second blocks but the sentence on the official upgrade page saying the activation height has not been set. Zcash upgrades trigger at a block height, which means that until a height is published, November 5 is only an engineering target and every expectation built around that date lacks any binding force. The practical consequence is that the deadline for migrating Sprout funds depends on the activation height, so holders of those assets currently face an action requirement with no fixed deadline, and that deserves earlier attention than any technical parameter.

 

Two misreadings are especially likely. The first treats the issuance adjustment as inflation or a supply cut. Dividing the per-block reward by three while tripling the halving interval is a mutually offsetting pair, leaving the issuance rate per unit of wall-clock time unchanged along with the 21 million cap and the halving schedule. What actually changes distribution is the fee reserve, which removes 60% of each block's fees from circulation temporarily and plans to return them starting February 2031, an arrangement that drew 96.6% coinholder support. The second reads a shorter block interval as a threefold throughput increase. The Zebra release notes simultaneously set per-block shielded limits, so capacity expansion comes from block count rather than per-block capacity, meaning what genuinely improves is confirmation latency rather than a multiple on shielded actions per unit of time.

 

For miners, the economic implication has been under-discussed. Before February 2031, coinbases claim only the 40% fee share, a change in income structure fixed by a governance vote rather than a temporary parameter. The cadence of miner income also changes once the interval shortens, with the per-block reward falling to a third while block count triples, leaving the total unchanged but the variance profile different. Smaller miners see a smoother income distribution, while pools dependent on fee income feel the effect more directly.

 

For investors, the most practical framing treats this as an infrastructure event rather than a price event. ZEC fell roughly 29% from near $1,600 in late September to around $1,140, a path with no clear correspondence to upgrade progress, and the analysis cited above notes the upgrade does not directly create token demand. The more informative metric is shielded transactions reaching as much as 56% of activity, because that measures how far the network is actually used for private payments, which is precisely the use case 25-second confirmations aim to improve. Whether the infrastructure improvement converts into sustained usage growth will only become visible several quarters after activation.

 

 

 

That remains undetermined. The mainnet target date is November 5, but both the official Zcash upgrade page and the Zcash Foundation's Zebra 7.0.0-rc.0 release notes state that no mainnet activation height has been set. Zcash upgrades trigger at a block height rather than a calendar date, so until a height is published November 5 is a plan rather than a commitment. Per the forum timeline the final decision was scheduled for October 20, while Blockhead reported on October 21 that it was set for that day.

 

 

It has been running for two weeks. NU7 activated on the public testnet at height 4,465,026, with the Zebra 7.0.0-rc.0 release notes giving an expected date around October 6 while Blockhead reports it actually went live on October 4, slightly ahead of schedule. Note that Zebra 7.0.0-rc.0 is a release candidate rather than a stable release, and the notes also state that mainnet operators need take no action yet.

 

 

Per ZIP 218 the target block interval falls from 75 seconds to 25 seconds, shortening the average wait for a first confirmation to roughly 25 seconds. The practical value concentrates in situations requiring a fixed confirmation count, and per CoinDesk the time an exchange or bridge needs before releasing ZEC falls to roughly a third. It does not amount to a threefold throughput increase, because Zebra simultaneously sets per-block shielded limits, so capacity expansion comes from the increased number of blocks.

 

 

Neither. The per-block reward is divided by an additional factor of three while the halving interval extends from 1,680,000 blocks to 5,040,000, and the two adjustments offset so that the issuance rate per unit of wall-clock time stays the same, expressed in the Zebra release notes as unchanged daily issuance. The 21 million cap and the halving schedule are both unchanged, and 98.9% of coinholders voting backed keeping the halving schedule.

 

 

It introduces the Network Sustainability Mechanism. Per ZIP 235 as described in the Zebra release notes, 60% of each block's transaction fees enter a reserve while miners keep 40%, and per ZIP 237 each block reissues a small, predictable portion of that reserve on top of its normal reward. The arrangement to return fees to miners begins in February 2031, a date backed by 96.6% of coinholders voting. The forum timeline lists this as ZIP-234 (alt) and ZIP-235, numbering that differs from the implementing team's.

 

 

It depends on the role. Ordinary holders need essentially no action, with the forum timeline describing wallets as largely unaffected. Node operators must act, since the official upgrade page states zcashd will not support this upgrade and operators need to switch to Zebra. ASIC miners themselves need no action and depend on their pool upgrading its nodes. The only group that must act before a deadline is anyone holding assets in the Sprout pool.

 

 

They need moving before activation. NU7 disables legacy v4 transactions, which closes the Sprout shielded pool. Per Blockhead's reporting the pool held roughly 22,309 ZEC on October 17, around $26 million or 0.13% of supply, and holders retain their keys but cannot spend those assets normally on the upgraded network unless they move them beforehand. Because the migration deadline depends on an activation height not yet set, the prudent approach is to complete the transfer without waiting for the deadline to be announced.

 

 

The information above is provided for general technical and market information only and does not constitute investment advice, financial advice, legal advice, tax advice or a recommendation to trade. Digital asset prices can fluctuate sharply, and past performance does not guarantee future results. The network upgrade described has not activated on mainnet, no mainnet activation height had been set at the time of writing, November 5 is a target date published by the development teams rather than a commitment, and the relevant parameters, dates and implementation arrangements may change or be deferred, with the official upgrade page, Zcash Foundation release notes and formal announcements from the development teams governing. This article distinguishes explicitly between changes live on testnet, changes planned for mainnet and unconfirmed information, and material cited from community forums represents community discussion rather than official commitments and should not be treated as a basis for action. Operations involving fund migration, node upgrades and software versions carry technical risk, and incorrect execution may render assets inaccessible, so readers should complete backups and verify official documentation before acting. Readers should conduct their own research and make decisions based on their own financial circumstances, investment objectives and risk tolerance, consulting a qualified professional where appropriate. The MEXC Crypto Pulse team accepts no liability for any direct or indirect loss arising from the use of this information.

 

 

James Mitchell specializes in technical analysis, market trends, and trading strategies for both Bitcoin and altcoins. Based in London, he has over 10 years of experience in financial markets. Before joining MEXC Learn, James worked as a senior analyst at a leading European investment firm, where he developed expertise in risk management and quantitative trading. His transition to cryptocurrency markets began in 2017, and he has since become recognized for his data-driven approach. He holds a Master's degree in Financial Economics from the London School of Economics. His analytical approach combines traditional technical analysis with on-chain metrics to provide readers with actionable insights.

 

Areas of Expertise: Technical Analysis, Market Trends and Cycles, Trading Strategies, Bitcoin and Altcoin Analysis, Risk Management.

 

 

 

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