Status at original publication: scheduled, not confirmed activated. Decrypt reported on November 6, 2026, at 03:46:03 UTC+08:00 that Zcash’s NU7 upgrade was expected to activate Thursday evening in the United States. Activation was tied to block 3,543,405, rather than a fixed clock time.
According to ZecStats data updated Thursday, approximately 12,224 ZEC remained in Sprout, Zcash’s original privacy pool. Decrypt valued those holdings at roughly $15 million–$16 million at then-recent market prices.
Activation timeline and withdrawal cutoff
At publication, the latest available block was 3,543,027. The source did not confirm that NU7 had activated.
Under the upgrade’s rules, version-4 transactions—the only transaction format capable of moving coins out of Sprout—would become invalid at block 3,543,405. Any ZEC remaining in the pool would therefore become unspendable, even if its owners retained their wallet passwords and private keys.
ZecStats described the outcome as “frozen, not burned.” The coins would continue to count toward Zcash’s circulating issuance calculations. A future upgrade could theoretically restore access, but that was not guaranteed. Decrypt reported that the team had shown no interest in doing so, and the technical specification explicitly warned that spending might never be re-enabled.
Why Sprout was being retired
Zcash uses zero-knowledge proofs to validate transactions without revealing private details, allowing users to conceal amounts and addresses. Sprout introduced that privacy technology at Zcash’s launch in 2016. Later systems included Sapling, Orchard and Ironwood.
Sprout had already been closed to new deposits for years, while withdrawals remained possible. NU7 would remove that remaining exit route by retiring version-4 transactions.
The reported rationale was to reduce the complexity and potential security vulnerabilities associated with maintaining obsolete technology. Sprout’s original system required substantial computing resources, and developers wanted to eliminate risks associated with its outdated transaction-verification mechanisms.
Which holders were affected?
At the time of reporting, holders with ZEC still in Sprout needed to use a compatible withdrawal mechanism before activation to avoid potentially indefinite loss of access. Sprout addresses begin with zc, which can help identify older wallet records.
Regular ZEC holders using modern supported wallets did not need a Sprout migration, although keeping wallet software updated remained important.
The blockchain could not identify the owners of the remaining Sprout balance. It was therefore unknown how much belonged to active users and how much was already inaccessible because owners had lost their keys.
Other scheduled NU7 change
According to the Zcash Foundation, NU7 would also reduce the target block interval from 75 seconds to 25 seconds, meaning transactions should receive their first confirmation approximately three times faster.
These were the expected effects documented at publication, not a retrospective confirmation that activation or withdrawals had occurred.
Original source: Decrypt — “Zcash Upgrade Could Lock $16 Million in Crypto Forever”, published November 6, 2026, at 03:46:03 UTC+08:00.
