Withdraw from Citrea

Use this guide to move sGUSD, GUSD, or GenericUnitL2 from Citrea to Ethereum without the Generic app. You will prepare the balance, quote the LayerZero fee, submit one cross-chain message, and finish the withdrawal on Ethereum.

Prepare Citrea and Ethereum gas

You need cBTC on Citrea for contract gas and the LayerZero fee. You also need ETH on Ethereum for the final GUSD unwrap and vault redemption.

If Citrea is missing from your wallet, add this network:

Confirm that your wallet displays Citrea chain ID 4114 before signing a Citrea transaction.

Check the contracts used in this route

Use the proxy address when CitreaScan displays a proxy and implementation pair:

All token amounts in this Citrea route use 18 decimals.

Redeem sGUSD into GUSD

Skip this section if you hold GUSD or GenericUnitL2. The sGUSD vault redeem function burns shares and returns GUSD.

1. Open the sGUSD contract on CitreaScan.
2. Open Read Proxy and call balanceOf with your wallet address.
3. Call maxRedeem with your wallet address.
4. Choose a share amount no greater than either result.
5. Call previewRedeem with that share amount and record the GUSD result.
6. Open Write Proxy and connect the sGUSD owner wallet.
7. Find redeem and enter these parameters:

8. Submit the transaction and wait for CitreaScan to show Success.
9. Read GUSD balanceOf to confirm receipt.

When the connected wallet is also owner, call redeem without an sGUSD approval.

Add the coordinator interface to CitreaScan

CitreaScan currently recognizes BridgeCoordinatorL2 as a proxy but does not expose its implementation functions. Add the withdrawal interface as a custom Application Binary Interface (ABI).

Skip this section if CitreaScan already shows both encodeBridgeMessage and bridge under Read Proxy and Write Proxy.

1. Sign in to CitreaScan.
2. Open your account menu and select Custom ABI.
3. Select Add Custom ABI.
4. Enter 0x6E810122C2B7d474Ef568bdf221ec05f2dC8063A as the contract address.
5. Enter Generic Citrea withdrawal as the project name.
6. Open the minimal coordinator ABI and copy the complete JSON array.
7. Paste the array into Custom ABI and save it.
8. Return to the BridgeCoordinatorL2 contract page.

CitreaScan should now show Read Custom and Write Custom. The custom ABI only exposes the two functions required by this guide.

Prepare the bridge values

The fee quote and bridge transaction must describe the same message. Prepare these values before approving a token:

Convert your wallet address to bytes32 by removing 0x, adding 24 zero hexadecimal characters to the left, then restoring 0x. For example:

Wallet:  0x1234567890123456789012345678901234567890
bytes32: 0x0000000000000000000000001234567890123456789012345678901234567890

Use the same wallet bytes32 for sender and recipient. Keep the original 20-byte wallet address for onBehalf.

Choose the source token values

Your source balance determines which contract to approve and which whitelabel values to use:

Call balanceOf on the token to obtain your amount. The amount used in the approval, message, fee quote, and bridge must match exactly.

Approve the coordinator

Approve only the amount you plan to bridge:

1. Open your source token on CitreaScan.
2. Use Write Proxy for GUSD or Write Contract for GenericUnitL2.
3. Connect the token owner wallet.
4. Find approve and enter these parameters:

5. Submit the approval and wait for CitreaScan to show Success.
6. Use allowance to confirm that BridgeCoordinatorL2 can spend the amount.

Do not approve the LayerZero adapter. BridgeCoordinatorL2 is the contract that unwraps or burns the source token.

Encode the LayerZero message

Use BridgeCoordinatorL2 Read Custom to create the byte string required for the fee quote:

1. Open encodeBridgeMessage.
2. Fill the message tuple with these fields:

3. Select Query.
4. Copy the complete returned bytes value.

Keep this browser tab open. Changing any tuple field requires a new encoding and fee quote.

Quote the LayerZero fee

The adapter calculates the required cBTC value from the encoded message:

1. Open the LayerZero adapter on CitreaScan.
2. Open Read Contract.
3. Find estimateBridgeFee.
4. Enter these parameters:

5. Select Query and copy the returned nativeFee integer.

The quote uses cBTC base units. Query it immediately before submitting bridge, because LayerZero fees can change.

Submit the bridge transaction

Call bridge on the coordinator proxy, not on the LayerZero adapter:

1. Return to BridgeCoordinatorL2 on CitreaScan.
2. Open Write Custom and connect the wallet that owns the approved token.
3. Find bridge and enter these parameters:

4. Enter nativeFee in the payable transaction value field. Use the base-unit or wei option if CitreaScan displays a unit selector.
5. Select Write and review the transaction in your wallet.
6. Confirm that the transaction destination is BridgeCoordinatorL2.
7. Confirm that the transaction value matches the quoted nativeFee.
8. Submit the transaction and save its Citrea transaction hash.

The wallet also charges Citrea gas. The LayerZero fee is separate from that gas charge.

Wait for Ethereum delivery

A successful Citrea transaction confirms that BridgeCoordinatorL2 submitted the source message. It does not confirm Ethereum delivery.

Track the transfer in this order:

1. Confirm that CitreaScan shows the source transaction as Success.
2. Search the transaction hash on LayerZero Scan.
3. Wait for the LayerZero message to show Delivered.
4. Open Ethereum GUSD on Etherscan.
5. Call balanceOf with the Ethereum recipient address.

After the GUSD arrives, continue with Unwrap GUSD into GenericUnit. Finish by redeeming GenericUnit through your chosen Ethereum vault.

Resolve common Citrea errors

Use the original transaction hashes and message values before attempting another write:

• The approval succeeded but bridge reverts: confirm the amount, allowance, source whitelabel, and a fresh nativeFee
• CitreaScan does not show coordinator functions: add the minimal custom ABI to the coordinator proxy address
• The source transaction is pending: do not submit another bridge
• The source succeeded but LayerZero is pending: keep tracking the original hash and do not bridge the same tokens again
• LayerZero shows delivered but GUSD is missing: verify remoteRecipient and destinationWhitelabel, then provide both transaction hashes to support
• LayerZero reports a failed destination execution: do not call rollback without protocol support, because rollback requires the original encoded message and a new bridge fee