Bridging overview

Token bridging and cross-chain messaging are fundamental aspects of building on Arbitrum. This page helps you find the right guide for your use case.

Move ETH between chains

• Deposit ETH to Arbitrum: Bridge ETH from the parent chain to a child chain using the Inbox contract
• Withdraw ETH to Ethereum: Withdraw ETH from a child chain back to the parent chain via ArbSys

Move ERC-20 tokens between chains

• Deposit tokens to Arbitrum: Move ERC-20 tokens from the parent chain to the child chain
• Withdraw tokens to Ethereum: Move ERC-20 tokens from the child chain back to the parent chain

Make my token bridgeable

Choose a gateway based on your token's requirements:

• Standard gateway (recommended): Automatic deployment of a standard ERC-20 on Arbitrum, no configuration required
• Generic-custom gateway: Custom functionality in your child chain token while using Arbitrum's built-in gateway
• Custom gateway: Specialized gateway logic for advanced use cases

Send arbitrary cross-chain messages

• Parent → child messaging: Send messages from Ethereum to Arbitrum using retryable tickets
• Child → parent messaging: Send messages from Arbitrum to Ethereum via ArbSys and the Outbox

Build on a custom gas token chain

If you're working with an Arbitrum chain that uses a non-ETH gas token, see Custom gas token chain bridging for SDK APIs and workflows.

Example code

• Token deposits (parent → child)
• Token withdrawals (child → parent)
• Custom token bridging setup

Learn more

• Cross-chain messaging concepts
• Token bridge architecture
• Arbitrum SDK documentation