Zcash has three older shielded pools, and only one of them has a shutdown date. On November 5, NU7 will make the 22,263 ZEC left in Sprout unspendable.
The 346,000 ZEC still in Orchard and the 420,000 ZEC in Sapling face no deadline at all.
But the Zcash specifications include one conditional warning that covers all three pools, and it has been widely misquoted. Let’s go through the ZIPs to set out exactly what each document says about each pool, and what it doesn’t.
Three Old Pools, One Deadline
Zcash keeps value in separate pools, and each one is tied to a generation of its privacy technology. As of October 25, community tracker ZecStats reports:
- Sprout, the original pool: 22,263 ZEC, marked “closing”
- Sapling: 420,000 ZEC, open
- Orchard: 346,000 ZEC, sealed and migrating
- Ironwood, the new pool introduced in NU6.3: 4.18 million ZEC
Together, the three older pools hold about 788,000 ZEC. Any full node reports these balances directly through the valuePools field of its getblockchaininfo RPC, so anyone running a node can check them.
The three pools are on very different paths. Sprout has a fixed end. Orchard is closed to new deposits, but no spec sets a closing date. Sapling remains a supported pool.
Sprout: The Only Pool With an End Date
Sprout’s end has been planned for years. ZIP 211, written in 2019, stopped new value from entering Sprout. It described that as “a step toward being able to remove the Sprout shielded protocol.”
ZIP 2003 takes the final step. It doesn’t target Sprout directly. Instead, it bans an entire transaction format: from NU7 onward, “the transaction version number MUST be 5 or 6.” Sprout transfers can only be written as version 4 transactions, so Sprout funds can no longer be spent.
ZIP 259, the NU7 deployment spec, sets the activation height at block 3,543,405 on mainnet. It states the result directly: “funds remaining in the Sprout pool become unspendable.”
The wording matters. ZIP 2003 says it does not “unissue, burn, or otherwise make Sprout funds permanently unavailable.” The coins stay counted in Zcash’s issued supply, and the ZIP leaves open “the theoretical possibility of re-enabling v4 transactions, or of adding another facility to retrieve these funds.” It also cautions that this “may never be re-enabled.”
Recovering Sprout funds was already hard before the deadline. According to ZIP 2003, the retirement of zcashd just before NU6.3 “removed the only maintained software that still provided wallet functionality for Sprout.” The pool has barely changed in the last few weeks: the widely reported figure of 22,309 ZEC has fallen only to 22,263, so about 46 ZEC has moved out since.
Orchard: Sealed, Shrinking, but Not Scheduled to Close
Orchard’s situation is newer and more unusual. ZIP 258 activated NU6.3 at block 3,428,143 and sealed Orchard after a soundness vulnerability was found and fixed. Since then, the consensus rules have enforced three restrictions:
- No new value may enter Orchard, including through mining rewards.
- Transfers between different users’ addresses are disabled within Orchard.
- Value may still leave, including across the “turnstile” into the Ironwood pool.
ZIP 229 explains why: Orchard held “a substantial portion of ZEC” when the vulnerability was fixed, so moving those funds to a fresh pool was meant to restore confidence in Zcash’s total supply.
The migration has largely worked. ZecStats counts 3,278,499 ZEC moved out of Orchard, about 90.5% of what was in the pool at NU6.3. That leaves about 346,000 ZEC, roughly 2% of the circulating supply.
What no ZIP includes is a date when Orchard stops working. The rules make Orchard one-way, so holders can leave but can’t add or pay anyone else. They don’t make it a countdown. ZIP 318, the wallet guide for the migration, focuses on how to move funds without revealing balances. It recommends splitting balances into standard amounts, sending them over time and leaving a small remainder unmigrated. That’s guidance on privacy, not a deadline.
Sapling: Still Open, Still Supported
Sapling has the fewest restrictions of the three. Version 6 transactions support it as one of the “supported shielded pools,” alongside Orchard and Ironwood, and none of the NU6.3 or NU7 ZIPs restricts it.
There’s one catch for Sapling users that many people are missing. ZIP 259 says the version 4 ban covers “all version 4 transactions, including transparent-only and Sapling transactions, not only Sprout transfers.” Sapling funds stay spendable after NU7, but only through version 5 or version 6 transactions. Wallets still building version 4 transactions need to switch before the upgrade. Pending or offline-signed version 4 transactions won’t confirm afterward, and “re-signing alone cannot make a version 4 transaction valid.”
Where the “Inaccessible” Warning Actually Comes From
The sentence behind the “inaccessible funds” headlines appears in ZIP 2005, “Ironwood Quantum Recoverability,” and is repeated in ZIP 229:
“Recovery would not be possible for funds still in the Sprout, Sapling, or Orchard pools; all such funds would be inaccessible after their respective protocols are disabled.”
The sentence before it explains the context. Zcash’s existing shielded protocols depend on discrete logarithms being hard to compute. If an attacker, using a quantum computer or another method, could break that, the protocols might have to be disabled “to prevent such attacks.” Only funds in Ironwood would be recoverable, through a recovery protocol designed to stay secure against quantum attacks.
So this is a contingency, not a schedule. It describes what would happen to funds in the older pools if a future cryptographic emergency forced Zcash to shut them down. No ZIP proposes doing that on any date. The practical advice behind it is plain: funds in Sprout, Sapling or Orchard “should be migrated to the Ironwood pool” to be covered by recovery.
What Node Operators and Holders Need Before Block 3,543,405
The software is ready. The Zcash Foundation released Zebra 7.0.0 on October 22. Its changelog says it “supports the NU7 network upgrade on Mainnet, which activates at height 3,543,405.” The release moves Zebra’s database from format v28 to v29. Zebra 6.x can’t read the new format, so the Foundation recommends backing up the old state first. The zcashd compatibility sidecar must also be updated to zebra-compat-v1.3.0. Earlier builds can’t follow mainnet past NU7.
This upgrade carries more risk than usual. ZIP 259 waives Zcash’s usual rule that old software must shut itself down before an upgrade. The spec warns that “operators of unsupported software may therefore remain online at activation and follow a pre-NU7 consensus branch.”
For holders, the guidance from each pool’s spec comes down to this:
- Sprout: move funds before block 3,543,405. Afterward, there’s no supported way to spend them.
- Orchard: no deadline, but the specs consistently point toward Ironwood, the only pool covered by quantum recovery.
- Sapling: spendable after NU7 through version 5 or version 6 transactions, with no sunset on record.
On November 5, Sprout closes. The 766,000 ZEC in Sapling and Orchard face no deadline, but the specs still recommend moving it to Ironwood.
Disclosure: This is not trading or investment advice. Always do your research before buying any cryptocurrency or investing in any services. Follow us on X @nulltxnews
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