> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/mezo-org/documentation/llms.txt
> Use this file to discover all available pages before exploring further.

# MUSD Bridge

> Learn how to bridge MUSD tokens between Ethereum and Mezo using Wormhole's Native Token Transfer protocol.

The [MUSD](https://mezo.org/feature/musd) bridge enables transfers between Mezo and Ethereum networks using Wormhole's Native Token Transfer (NTT) protocol. This bridge maintains token fungibility while providing secure cross-chain functionality.

## How It Works

The MUSD bridge uses Wormhole's Native Token Transfer protocol to facilitate cross-chain transfers:

<Info>
  * **From Mezo to Ethereum**: MUSD tokens are locked on Mezo and the equivalent tokens are minted on Ethereum
  * **From Ethereum to Mezo**: MUSD tokens are burned on Ethereum and equivalent tokens are unlocked on Mezo
</Info>

This mechanism ensures that the total supply across both chains remains constant while allowing users to move their tokens freely between networks.

## Using the Portal UI

The easiest way to bridge MUSD tokens is through the [Portal UI](https://portalbridge.com/):

<Steps>
  <Step title="Connect Your Wallet">
    Connect your wallet to the Portal interface. Make sure you have the network you're bridging from set as your active network.
  </Step>

  <Step title="Select Source and Destination Chains">
    Choose either Mezo → Ethereum or Ethereum → Mezo depending on which direction you want to bridge.
  </Step>

  <Step title="Choose MUSD Token">
    Select MUSD as the token to bridge. The Portal will automatically detect your MUSD balance.
  </Step>

  <Step title="Enter Amount">
    Enter the amount of MUSD you want to bridge. Make sure to leave enough for gas fees on the source chain.
  </Step>

  <Step title="Review Transaction Details">
    Review the transaction details including:

    * Bridge fees
    * Estimated transfer time
    * Destination address
    * Total amount to receive
  </Step>

  <Step title="Confirm Transaction">
    Confirm the transaction in your wallet. You'll need to approve the MUSD spend first, then confirm the bridge transaction.
  </Step>

  <Step title="Wait for Confirmation">
    Wait for confirmation on both chains. The Portal UI will show you the progress of your transfer. This typically takes a few minutes.
  </Step>
</Steps>

<Note>
  The Portal UI provides a user-friendly interface that handles all the complex interactions with the underlying NTT contracts.
</Note>

## Smart Contracts

The MUSD bridge is powered by the following smart contracts:

### Mezo Network

* **NTT Manager**: [0x7efb386675d75280D39Aae42964A6776DE0ee0bD](https://explorer.mezo.org/address/0x7efb386675d75280D39Aae42964A6776DE0ee0bD)
* **Wormhole Transceiver**: [0x56E27f1A8425515FFD4BD76A254Ac1a5c0B66D71](https://explorer.mezo.org/address/0x56E27f1A8425515FFD4BD76A254Ac1a5c0B66D71)
* **MUSD Token**: [0xdD468A1DDc392dcdbEf6db6e34E89AA338F9F186](https://explorer.mezo.org/token/0xdD468A1DDc392dcdbEf6db6e34E89AA338F9F186)

### Ethereum Network

* **NTT Manager**: [0x5293158bf7a81ED05418DA497a80F7e6Dbf4477E](https://etherscan.io/address/0x5293158bf7a81ED05418DA497a80F7e6Dbf4477E)
* **Wormhole Transceiver**: [0x76ddB3f1dDe02391Ef0A28664499B74C29d18d3E](https://etherscan.io/address/0x76ddB3f1dDe02391Ef0A28664499B74C29d18d3E)
* **MUSD Token**: [0xdD468A1DDc392dcdbEf6db6e34E89AA338F9F186](https://etherscan.io/address/0xdD468A1DDc392dcdbEf6db6e34E89AA338F9F186)

<Warning>
  Always verify you're interacting with the correct contract addresses. The addresses above are the official MUSD bridge contracts.
</Warning>

## Bridge Security

The MUSD bridge leverages Wormhole's proven security model:

* **Decentralized Guardian Network**: 19 guardians validate cross-chain messages
* **Lock and Mint Mechanism**: Ensures total supply remains constant
* **Audited Smart Contracts**: All contracts have been audited by leading security firms
* **Real-time Monitoring**: Bridge activity is monitored 24/7

## Troubleshooting

<Accordion title="My tokens haven't arrived yet">
  Bridge transfers typically take 2-5 minutes. If your tokens haven't arrived after 10 minutes:

  1. Check the transaction status on the Portal UI
  2. Verify the transaction was confirmed on the source chain
  3. Check if you need to manually claim on the destination chain (rare)
</Accordion>

<Accordion title="Transaction failed">
  If your bridge transaction failed:

  1. Ensure you have enough gas on the source chain
  2. Check that you approved the MUSD spend
  3. Verify you're connected to the correct network
  4. Try again with a higher gas price if network is congested
</Accordion>

<Accordion title="Wrong network in wallet">
  Make sure your wallet is set to:

  * **Mezo Mainnet** when bridging from Mezo
  * **Ethereum Mainnet** when bridging from Ethereum

  The Portal may prompt you to switch networks automatically.
</Accordion>

## Additional Resources

* [Wormhole NTT Documentation](https://wormhole.com/docs/products/native-token-transfers/overview/) - Learn more about the Native Token Transfer protocol
* [Portal Bridge](https://portalbridge.com/) - The official UI for bridging tokens
* [Contracts Reference](../../resources/contracts.md) - Complete list of all protocol contracts