Harmony May Shut Down: What ONE Holders Should Do by September 10

Harmony is shutting down its Layer 1 blockchain, and if you hold ONE tokens, there's a real deadline attached: September 10, 2026, at 7 a.m. Pacific Time. For most holders, the migration to a new Ethereum-based ONE token happens automatically. 

But if your ONE is sitting in a multisig wallet, a liquidity pool, or a lending protocol, doing nothing could mean losing it. Here's exactly what's changing, why Harmony is shutting down, and what you need to check before the cutoff.

Key Takeaways

• Harmony announced on September 6, 2026, that it will fully sunset its Layer 1 blockchain, citing security threats from "state actors and AI agents," and will migrate the ONE token to a new ERC-20 version on Ethereum via a snapshot taken September 10, 2026, at 7 a.m. Pacific Time (14:00 UTC).

• Most holders don't need to do anything: tokens in regular wallets, staking delegations, and centralized exchange balances will be airdropped automatically to the same address on Ethereum. But ONE held in multisig wallets, liquidity pools, or lending protocols will not migrate automatically and must be withdrawn to a standard wallet before the cutoff.

• The shutdown follows a massive August 2026 exploit in which an attacker minted more than 3 trillion unauthorized ONE tokens by exploiting a flaw in Harmony's cross-shard receipt verification, the latest in a string of security incidents dating back to a $100 million bridge hack in 2022 attributed to North Korea's Lazarus Group.

Why Is Harmony Shutting Down?

Source: x.com/@harmonyprotocol

Harmony announced the decision on X on September 6, 2026, framing it as a response to escalating security threats: "The threats posed by state actors and AI agents are too great," the team wrote. "Since our mainnet launch in 2019, our community has been resilient through attacks and changes, but it is time to fully sunset the Harmony network."

Rather than simply winding down, Harmony says it's pivoting into a new venture centered on AI-generated video, which it's calling a "remix economy." Under the proposed model, a small group of AI video creators would publish open prompts and source assets, fans would "remix" those originals, and AI agents would generate many derivative clips from each fork. 

Harmony says advertising around this new economy "could generate tens of millions of dollars from a million users." Validators are being offered a path into this new initiative as "governors," and the project has set aside a $1.37 million pool to compensate validators who sunset their nodes, sign a transition agreement, maintain their stakes, and move into these new roles.

The Exploit Behind the Decision

This shutdown doesn't come out of nowhere. In August 2026, Harmony confirmed a major exploit in which an attacker initially appeared to have minted 4 billion unauthorized ONE tokens. A later, more complete reconstruction by Harmony's own team found the real scale was far larger: more than 3 trillion ONE tokens minted across six transactions.

The root cause was a flaw in Harmony's cross-shard receipt verification system, which allowed valid receipts to be processed multiple times, letting the attacker mint new tokens without any corresponding debit elsewhere in the system. 

A separate bug in the network's pre-staking quorum-checking system was also flagged. Harmony rolled the network back to a point before the exploit and, even at that time, said it was considering a full token migration as a possible response.

This is also not Harmony's first major security failure. In June 2022, the project's Horizon cross-chain bridge was exploited for nearly $100 million in stolen assets, an attack the FBI later attributed to North Korea's Lazarus Group and APT38. Taken together, this shutdown follows a pattern of serious, recurring security incidents rather than a single isolated event.

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Harmony ONE Token Migration: The Key Date

Mark this down: the migration snapshot is scheduled for Thursday, September 10, 2026, at 7 a.m. Pacific Time (14:00 UTC). At that moment, Harmony will record ONE balances across wallets, staking delegations, validator rewards, and centralized exchange accounts, and airdrop an equivalent amount of a new Harmony ERC-20 token on Ethereum to the same wallet addresses. 

Total token supply and the emission rate are staying the same, with newly issued tokens going toward funding the new AI video initiative. Exchange listings are also expected to migrate alongside the token itself.

What Happens Automatically (No Action Needed)

For most holders, this genuinely requires no action:

• Standard wallet balances are captured at the snapshot and airdropped automatically to the same address on Ethereum.

• Staking delegations convert automatically too: your validator becomes the "governor" of an ERC-4626 vault on Ethereum, and your delegated ONE is deposited into that vault as vault shares. You can withdraw (subject to a delay similar to a normal undelegation) or deposit further, and you continue earning rewards from the governor's reward pool proportional to your delegation, minus the governor's fee.

• Validator rewards and centralized exchange balances are included in the same snapshot process.

What You Must Do Before September 10

This is the part that actually requires action, and missing it could mean losing funds:

1. Multisig or smart contract wallets (Harmony Multisig, 1wallet, or similar): Withdraw your assets to a simple externally-owned wallet, such as a Ledger, MetaMask, or command-line wallet, before the cutoff. Smart contracts will not be migrated automatically. If you want to keep using a multisig setup afterward, create a Gnosis Safe on Ethereum first, move your Harmony assets to a standard wallet before the deadline, wait for the ERC-20 ONE airdrop to that wallet, then transfer the new tokens into your Gnosis Safe.

2. Liquidity pools or lending protocols: Withdraw your ONE or any bridged assets to a standard wallet as soon as possible. Harmony's own guidance is direct on this point: funds may be lost if you don't act before the cutoff, since these positions will not be migrated.

3. Bridged assets held on Harmony (assets that originated on another chain): A claim contract will be made available on the original chain, letting you claim the underlying asset back 1:1 to the same wallet address. This process has more flexibility than the hard snapshot cutoff, but it's worth handling promptly regardless.

4. WONE held on other chains (such as BSC or Ethereum): A claim contract on Ethereum will let you claim new ERC-20 ONE at a 1:1 ratio. One important wrinkle: due to the August exploit, Harmony has noted there are roughly 2.412 billion forged WONE tokens still outstanding on BSC and about 12.9 million forged on Ethereum. Harmony says it will most likely use a pre-hack snapshot on those chains to calculate legitimate balances, meaning fraudulently created WONE from the exploit won't be honored in the migration.

Read Also: What is Onchain Reputation System?

What Won't Migrate at All

DApps and smart contracts built on Harmony will not be migrated under any circumstances. If you're a developer with an application on Harmony, the team's guidance is to redeploy on Ethereum directly.

ONE Token Price and Context

As of the shutdown announcement, ONE was trading around $0.00073, down 3.86% over the prior 24 hours, a small fraction of a cent that reflects the token's long decline well before this news. This context matters less for anyone focused on the migration mechanics above, but it's a useful reminder of how far the project has fallen from its earlier prominence.

Conclusion

Harmony's shutdown is unusual in that most holders genuinely don't need to do anything to keep their tokens: the migration to Ethereum is designed to happen automatically for standard wallets, staking positions, and exchange balances. 

The real risk sits specifically with multisig wallets, liquidity pools, and lending positions, all of which need manual action before the September 10 snapshot. If any of that applies to you, treat the next few days as the deadline they actually are.

Read Also: Japan Prepares to Adopt Blockchain for Real-Time Stock and Bond Transactions

FAQ

When is Harmony's shutdown deadline?

The migration snapshot is scheduled for September 10, 2026, at 7 a.m. Pacific Time (14:00 UTC).

Do I need to do anything with my ONE tokens?

If your ONE is in a standard wallet, staked with a validator, or held on a centralized exchange, no action is needed, it will migrate automatically. If it's in a multisig wallet, a liquidity pool, or a lending protocol, you need to withdraw it to a standard wallet before the cutoff.

What happens to ONE in a multisig or liquidity pool?

These will not migrate automatically. Harmony's guidance is to withdraw funds from liquidity pools and lending protocols immediately, and to move multisig holdings to a simple wallet like MetaMask or a Ledger before September 10, since smart contracts of any kind will not be migrated.

Why is Harmony shutting down?

Harmony cited escalating security threats from "state actors and AI agents," following a major August 2026 exploit in which an attacker minted more than 3 trillion unauthorized ONE tokens by exploiting a flaw in the network's cross-shard receipt verification system.

Will Harmony's dApps still work after the shutdown?

No. Applications and smart contracts on Harmony will not be migrated. Developers who want to continue operating are being directed to redeploy their applications on Ethereum.

Disclaimer: The views expressed belong exclusively to the author and do not reflect the views of this platform. This platform and its affiliates disclaim any responsibility for the accuracy or suitability of the information provided. It is for informational purposes only and not intended as financial or investment advice.