Deposits

In the context of Arbitrum Nitro, a deposit is a transaction initiated on base blockchain (e.g. a layer one blockchain like Ethereum Mainnet or layer two like Arbitrum one) and executed on the rollup (ie. a layer two like Arbitrum Nova or a layer three Orbit chain).

To maintain a shared language, Superbridge refers to bridge operations where tokens flow from the settlement chain to rollup deposits, and bridge operations where tokens flow from the rollup to the settlement chain as withdrawals.

How do deposits work?

Ether deposits are initiated by creating a Retryable on the Inbox. In most cases the Retryable should be auto-redeemed, meaning no further action is needed after initiating the deposit, the Ether should simply show up in your wallet on the rollup after about 10 minutes. In cases where the deposit is not auto-redeemed, a Redeem button will show in the activity log for this transaction, allowing you to manually redeem it.

ERC20 token deposits are initiated via calls to outboundTransferCustomRefund on the GatewayRouter.

Deposits take around 10 minutes to be finalized for mainnet deployments, and around 3 minutes for testnet deployments.

For a more comprehensive understanding of deposits, please refer to the Arbitrum Nitro documentation on deposits.