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Monero upgrade tracker

Monero FCMP++ upgrade: status, date and readiness

FCMP++ replaces Monero's ring signatures with full-chain membership proofs. This page tracks where the upgrade stands and which wallets and tools support it, from primary sources only.

Checked against the sources on

Is FCMP++ live?

Not yet on mainnet

As of 2026-09-19, FCMP++ is not live on Monero mainnet. It runs only on a public test network (the beta stressnet), which forked off Monero's testnet. No official mainnet fork height or date has been announced.

Latest test release
FCMP++ & Carrot beta stressnet v2.0 (v0.19.0.0-beta.2.0)
Published
27 May 2026
Network
beta stressnet (hard fork of Monero testnet)
Not working yet in this release
watch-only wallets and cold wallets, hardware wallets, multisig, transaction proofs

Sources

What FCMP++ changes

  • FCMP++ (Full-Chain Membership Proofs + Spend Authorization + Linkability) is a planned Monero upgrade that replaces ring signatures.
  • Today each input hides among 16 ring members. With FCMP++, a spend proves it uses one of all spendable outputs on the chain, which the developers put at more than 150 million.
  • Carrot is the addressing protocol that ships with FCMP++. Existing addresses keep working, and addresses from new-style Carrot wallets look the same as old ones.
  • Carrot adds protection against Janus and burning-bug attacks, forward secrecy against a future quantum attacker who does not know the receiver's address, and new view-key tiers for newly created wallets.
  • For users this means the same addresses, a much larger anonymity set, larger transactions, updated wallets that re-scan once, and no more custom unlock times.

Planned schedule

There is no official date. The only public timeline is a draft plan by a Monero developer, who calls it non-binding. Dates in it have moved before and can move again.

"This plan is a non-binding working draft." jeffro256 (Monero developer), 21 Aug 2026
StepPlanned windowState on the check date
Fork activation code merged to master2026-09-15 to 2026-09-16Not merged yet. The mainnet hard fork table has no FCMP++ entry.github.com/jeffro256/fcmp-carrot-plan
Pre-release code freeze2026-09-16 to 2026-10-14Plannedgithub.com/jeffro256/fcmp-carrot-plan
First fork-enabled binary release2026-10-14 to 2026-10-21Plannedgithub.com/jeffro256/fcmp-carrot-plan
Follow-up fix release2026-11-03 to 2026-11-10Plannedgithub.com/jeffro256/fcmp-carrot-plan
Fully-featured release (hardware wallets, multisig and other wallet features)2026-12-02 to 2026-12-09Plannedgithub.com/jeffro256/fcmp-carrot-plan
Waiting period before activation2026-09-16 to 2027-03-03Plannedgithub.com/jeffro256/fcmp-carrot-plan
Mainnet activation2027-03-03 to 2027-03-04 (week 9 of 2027)Plannedgithub.com/jeffro256/fcmp-carrot-plan

Readiness of wallets and tools

Each project starts at "no statement" and moves only when its own repository, website, release notes or a developer meeting log says so. Work in a library does not change the status of the apps built on it. Exchanges and swap services are out of scope.

42 projects: 0 ready, 3 in a test release, 11 in progress, 28 with no public statement.

Wallets

Hardware wallets

Libraries

Node software

Light-wallet servers

Block explorers

Payment tools for merchants

Mining

What changes for integrators

For wallets, merchants, explorers and services that run Monero software. Planned changes are labelled as planned in the sources.

Addresses

Existing addresses, subaddresses and integrated addresses keep working. No wallet key migration is needed. Wallets that use the new Carrot key setup make addresses in the same format, and they cannot be told apart from old ones. Integrated addresses still work, but one transaction can pay only one integrated address. The payment ID is now confirmed by a hash, which gives payment processors firmer checks.

unlock_time deprecation

Custom unlock times will be rejected at consensus with FCMP++. Nodes already refuse to relay such transactions under a relay rule added in 2024. Outputs locked in the past keep their original unlock times. New transactions created after 2026-06-01 with an unlock time past the fork unlock when the fork block arrives. Developers agreed to reserve unlock_time = 1 for a possible later relative lock. Whether the lock itself ships with this fork is not decided.

Transaction proofs and payment proofs

Transaction proofs did not work yet in beta 2.0. New Carrot and FCMP++ proof code (transaction, spend and reserve proofs) is in an open pull request. Reserve proofs will not reveal amounts per input or the total held, only that the amount is at least the stated threshold. Spend proofs keep full-chain sender privacy. In hot/cold setups, sender-receiver secrets are fetched from the cold wallet by the signable transaction hash, not the TXID. That is a breaking change for this wallet RPC flow.

Wallet files and keys

Old wallets keep their seeds and keys. When an old wallet file is opened with FCMP++ software, it re-scans once from its restore height to build its FCMP++ tree data. An updated wallet must connect to an updated node; old wallets can still use updated nodes. Carrot also defines a new key setup for new wallets, such as a view-balance secret and a generate-address secret. How the reference wallet will create and store these keys, and how seeds mark the wallet type, is still under discussion.

View-only wallets and view keys

Existing private view keys still find incoming payments. As today, a legacy view-only wallet cannot see spends on its own. Wallets that use the new Carrot key setup get more tiers: view-received (incoming only), view-all (a full view-only wallet that also sees spends and the right balance), and generate-address (makes addresses only, for point-of-sale use). Watch-only and cold wallets did not work yet in beta 2.0. The hot/cold wallet code was merged into the FCMP++ staging branch on 2026-09-14.

Hardware wallets

No hardware wallet supports FCMP++ yet. A device only needs to make the spend-authorization part of each proof, not the full membership proof. Monero developers published a guide for device makers. The draft plan puts Ledger and Trezor merges in late November 2026, ahead of a fully-featured release in early December 2026. These dates are non-binding.

RPC, transaction format and node changes

Apps that use the wallet API should see few changes; a lead developer said downstream apps like the GUI need almost none. Wallet RPC stays backwards compatible until the fork. After it, only the way transaction secret keys are fetched changes. The node sends new data so wallets can build FCMP++ tree data, and an RPC to fetch tree paths by output ID is still in review. Light-wallet servers get a new get_tree_paths call. FCMP++ transactions use RingCT type 7 with new fields (reference_block, n_tree_layers and the FCMP++ proof). Outputs use a new Carrot output type with a 3-byte view tag. Block explorers and transaction parsers need updates.

Fees and transaction size

FCMP++ transactions are larger. Development measurements from August 2025 put a 1-input, 2-output transaction at about 6.5 kB and a 2-input, 2-output one at about 7.9 kB. Transaction weight now closely follows byte size. A transaction can have up to 128 inputs and 16 outputs. Fee and block-size rules change with the fork; the staging code uses a reference transaction weight of 12,500 (3,000 today). Final values may still change. Building transactions with many inputs takes longer.

Old outputs and migration

Users do not need to move funds. All valid existing outputs, including pre-RingCT ones, enter the FCMP++ tree once they unlock, so the anonymity set covers about the whole chain. Legacy wallets get this without converting to Carrot. Nodes run a one-time database migration that can take several hours. Wallets re-scan once from their restore height.

Miners and pools

The proof-of-work hash also commits to the FCMP++ tree root and layer count. The block template layout changed during stressnet testing, and the miner reward outputs in each block use the Carrot format. P2Pool and solo-mining tools need updates (see the P2Pool and XMRig entries). RandomX v2 support for this fork is an open pull request and is not confirmed.

Common claims, checked

Claim: FCMP++ is already live on Monero mainnet.
What the sources say: False as of 2026-09-19. The mainnet hard fork table ends at version 16 from 2022. FCMP++ runs only on a public test network, and no official fork date is set.github.com/monero-project/monerogetmonero.org/2026/05github.com/seraphis-migration/monero
Claim: FCMP++ activated at block 2,847,330, 2,997,100 or 3,012,000.
What the sources say: Those are test network (stressnet) fork heights, not mainnet heights.github.com/seraphis-migration/monerogithub.com/seraphis-migration/monerogithub.com/seraphis-migration/monero
Claim: The code shows FCMP++ activating near block 2,689,609.
What the sources say: Those mainnet version 17 and 18 heights in the staging code are labeled 'Mock values for tests'.github.com/seraphis-migration/monero
Claim: Monero had a hard fork in 2026, for example in March 2026 with new ring-signature rules.
What the sources say: False. The last mainnet hard forks were versions 15 and 16 at blocks 2,688,888 and 2,689,608 in 2022.github.com/monero-project/monerogithub.com/monero-project/monero
Claim: Ledger and Trezor already support FCMP++.
What the sources say: False. The FCMP++ beta does not support hardware wallets yet, and developers say no device has been built for it yet.github.com/seraphis-migration/monerogithub.com/seraphis-migration/monero
Claim: You need a new address, or must move funds to a new wallet, to benefit.
What the sources say: False. Carrot keeps existing addresses. Legacy wallets get the full-chain anonymity set without converting.github.com/jeffro256/carrotgithub.com/seraphis-migration/monero
Claim: FCMP++ makes transactions smaller.
What the sources say: False. FCMP++ transactions are larger; a 1-input, 2-output transaction measured about 6.5 kB in development.github.com/seraphis-migration/monero
Claim: RandomX v2 is already active on Monero.
What the sources say: False. RandomX v2 support for the next fork is an open pull request, and there has been no mainnet fork since 2022. Miner software adding RandomX v2 support does not mean it is active.github.com/monero-project/monerogithub.com/monero-project/monerogithub.com/xmrig/xmrig
Claim: The FCMP++ fork date is fixed.
What the sources say: No official date exists. The only public timeline is a non-binding draft that currently says week 9 of 2027, and it moved three times in one month.github.com/jeffro256/fcmp-carrot-plangetmonero.org/2026/05

Use the data

The tracker is open data under CC BY 4.0: credit HiddenSwap with a link to this page. Project maintainers can correct their own row: send a link to your release notes or repository to contact@hiddenswap.com.

Questions

Is FCMP++ live on Monero?

No. As of the check date above, FCMP++ runs only on a public test network. The mainnet hard fork table in Monero's code has no FCMP++ entry, and no official fork height or date has been announced.

When will FCMP++ activate?

No official date exists. A developer's draft plan, which its author calls non-binding, currently puts mainnet activation in early 2027, with a first fork-enabled release before that. Check the schedule above for the latest window and its source.

Do I need a new Monero address?

No. Existing addresses, subaddresses and integrated addresses keep working, and new addresses look the same as old ones.

Do I need to move my Monero before the upgrade?

No. Existing outputs join the new anonymity set on their own. What you need is a wallet version that supports the upgrade once it is released.

Will my hardware wallet work?

Not yet: no hardware wallet supports FCMP++ so far, and the test release does not support them. The tracker shows the status of each device.