Sui Bridge

Sui Bridge is a bidirectional, open-source bridge operated by Sui validators rather than an external network: an Ethereum asset is locked and an equivalent Move coin type is minted on Sui, while the return route burns that Sui representation and releases the escrowed Ethereum asset. Its validator-operated model differs from third-party routes such as Wormhole, which use a separate guardian set, as described in Sui’s mainnet launch. The documented supported assets are WBTC, LBTC, ETH, WETH, and USDT; another asset needs a different route. A global limiter caps rolling outbound value and individual transfer size, so a large transfer can be throttled by design.

Bridging uses lock-and-mint from Ethereum to Sui and burn-and-claim on the return route. For a deposit, tokens enter the Ethereum bridge contract, bridge nodes independently verify the finalized deposit, and a permissionless client collects stake-weighted ECDSA signatures from the Sui Bridge Committee and submits them to the destination. The Sui package checks the threshold using recoverable secp256k1 signatures, then mints the Sui asset; returning burns that representation and requires a manual Ethereum claim to release escrowed funds. An ERC-20 standard token needs a separate allowance approval, and that approval only needs to cover the amount being bridged. The Sui bridging documentation shows the complete flow.

To deposit from Ethereum to Sui, connect both wallets, choose the asset and amount, confirm the recipient Sui address, approve the token allowance when the asset is an ERC-20, then sign the deposit. Bridge nodes verify it only after the Ethereum transaction finalizes, so minting follows Ethereum finality rather than a wallet confirmation toast; congestion on Ethereum can stretch the wait. Keep ETH for the approval and deposit gas, and keep a little SUI in the receiving wallet so you can use the bridged asset after it arrives. If the mint is missing, check the deposit transaction’s status on an Ethereum explorer before assuming failure.

To withdraw from Sui to Ethereum, burn the Sui-side asset, wait for the committee’s signatures to cover that burn, then submit the manual Ethereum claim that releases the escrowed tokens; the claim costs Ethereum gas. Burning alone does not complete the withdrawal, so do not resubmit the burn while it is pending. The outbound limiter can delay large withdrawals during high-volume periods, and the assets remain in escrow until the claim confirms on Ethereum.

Bridge fees are the chain-gas payments required by each transaction, not a flat quoted fee. A deposit uses Ethereum gas for the ERC-20 approval plus the deposit transaction; a withdrawal uses a Sui-side transaction plus Ethereum gas for the manual claim, usually the most expensive single step. Ethereum’s gas documentation explains the network-fee model; check the live estimate in your wallet before each signature because Ethereum gas varies over time. A third-party route can add a provider or relayer fee on top of gas, so read that quote line before confirming.

Sui Bridge’s security model is stake-weighted signatures from a committee of Sui validators, while bridged assets remain in escrow during transit; its v1 code was audited by OtterSec and Zellic. An audit does not remove smart-contract, validator, wallet, chain-finality, or operational risk, and fake interfaces or malicious approvals add user-side risk. Before signing, verify the interface URL and the Ethereum bridge contract at 0xda3bD1fE1973470312db04551B65f401Bc8a92fD. The interface does not ask for a seed phrase or private key; a site that does is phishing.

Fix the network, gas, or transaction-state mismatch first: the Ethereum wallet must be on Mainnet (chain ID 1), not a testnet or L2, and a destination Sui wallet with zero SUI cannot use the bridged asset until funded, so keep a small SUI balance there. For a pending deposit, check whether the Ethereum transaction finalized before resubmitting anything; for a pending withdrawal, check whether the manual Ethereum claim was submitted after the Sui burn.