When you transfer assets to a centralized exchange you send it to an address provided by that centralized exchange. By default, this is an Ethereum mainnet address and the exchange does not look at this address in Optimism. As a result, assets transferred directly to a centralized exchange that doesn't support Optimism are irrevocably lost, unless the exchange can help you. Don't do it.
Verify that the centralized exchange is supporting OP Mainnet and that it looks at the OP Mainnet account before you send it anything.
There are two ways to withdraw assets from OP Mainnet:
- The OP Mainnet Bridge. We have a list of supported ERC-20 tokens, but you are not limited to them, you can select any token that exists on both Ethereum mainnet and OP Mainnet.
Third-party bridges. Those bridges are usually cheaper and faster than our main gateway, but have a more limited list of supported tokens. When the bridge gets low on the asset in the Ethereum mainnet, it sends all of those tokens from OP Mainnet to Ethereum in one gateway transaction. This way: The way this works is that the bridge loans you the relevant asset on the Ethereum mainnet.
You don't have to wait the normal challenge verification period. The bridge takes the risk that the block with the transaction (or a prior one) is invalid. Bridges run their own verification so it's not a big risk for them.
The cost of the merkle proof required for a withdrawal transaction is spread over a larger pool of tokens, so the relative cost of the withdrawal is smaller.
Withdrawals using the OP Mainnet Gateway
Note that this is not the preferred solution. The OP Mainnet Gateway is trustless, which requires it to be slow and expensive. In almost all cases you would be better served by using a third party bridge.
Withdrawals through the OP Mainnet Gateway is a multi-step process:
Initiate the withdrawal on OP Mainnet.
- Wait until the withdrawals root is published on Ethereum, which is typically a few minutes, but could take longer in the case of an outage.
- Prove the withdrawal.
Wait the verification challenge period, which is seven days from the time the withdrawal is proved on Ethereum.
Claim the withdrawal.
Initiate the withdrawal
Click Connect Wallet, select your wallet type, and approve the connection in the wallet itself if asked.
- Select Withdraw.
- Select Using the official bridge.
- Select the asset and amount.
Click the check boxes and accept the withdrawal:
- Approve again in the wallet.
While waiting the verification challenge period
There are several ways to see if your withdrawal is ready to be claimed:
Browse to the gateway and click your address in the top right corner. Then click Withdrawals. This shows you the list of recent withdrawals and their status:
Search the transaction hash on the Etherscan message relayer. If the withdrawal is ready to be claimed, the Execute button will be enabled.
You can search for the transaction hash on Optimistic Etherscan. Click the L1 State Root Submission Tx to see when the transaction was written to Ethereum.
Claim the withdrawal
Once the challenge period is over, the status in the gateway changes to Claim.
- Click Claim.
- Confirm the withdrawal in the wallet.
- Wait until the withdrawal completes.
Note: If there is a problem with the bridge you can also use the Etherscan Message Relayer as a backup mechanism to claim withdrawals.