How to bridge assets to ZKsync via OKX? (L2 bridge tutorial)

Understanding ZKsync and OKX Bridge Integration

1. ZKsync is a Layer 2 scaling solution built on Ethereum using zero-knowledge rollup technology to enhance transaction throughput and reduce gas fees.

2. OKX operates an official cross-chain bridge that supports asset transfers between Ethereum mainnet and ZKsync Era, enabling users to move ETH, USDT, USDC, DAI, and other ERC-20 tokens.

3. The bridge relies on cryptographic proofs verified on Ethereum, ensuring funds remain secured by the same consensus mechanism as the base layer.

4. Users must hold assets on Ethereum mainnet before initiating any bridging action—no direct deposits from external chains like BSC or Solana are supported through this interface.

5. Transaction finality on ZKsync Era typically takes under 10 minutes after confirmation on Ethereum, with no additional custodial risk introduced by OKX during transit.

Prerequisites for Bridging via OKX

1. A verified OKX account with KYC level 2 completed to enable withdrawal privileges and higher transfer limits.

2. Sufficient ETH balance in your OKX spot wallet to cover both network fees on Ethereum and potential ZKsync Era activation costs.

3. Access to the OKX Web3 Wallet extension or a compatible external wallet (e.g., MetaMask) connected to OKX’s Web3 interface.

4. Accurate selection of network: Ethereum mainnet must be active in your wallet when sending; ZKsync Era must be selected when receiving or confirming receipt.

5. Awareness of minimum transfer thresholds—some tokens require at least 0.01 ETH equivalent to initiate bridging due to protocol-level constraints.

Navigating the OKX Bridge Interface

1. Log into OKX.com and navigate to the “Web3” section, then select “Bridge” from the left-hand menu.

2. Choose “Ethereum” as the source chain and “ZKsync Era” as the destination chain using the dropdown selectors.

3. Enter the token symbol and amount—OKX auto-detects balances across supported assets in your spot wallet.

4. Click “Preview Bridge” to view estimated time, fee breakdown, and destination address validation status.

5. Confirm the transaction in your connected wallet; signing triggers the Ethereum L1 deposit, which initiates the ZKsync rollup process.

Tracking and Confirming Bridged Assets

1. After signing, monitor the Ethereum transaction hash on Etherscan to verify inclusion in a block.

2. Once confirmed, OKX displays a “Pending on ZKsync” status while waiting for zkProof generation and verification.

3. Users can check finalization status directly in the OKX Bridge history panel or by querying their ZKsync Era address on https://zkscan.io.

4. Upon completion, assets appear in the OKX spot wallet under the ZKsync Era network tab without requiring manual import.

5. No additional claim step is needed—the bridge handles minting of canonical tokens on ZKsync Era automatically upon proof validation.

Frequently Asked Questions

Q: Can I bridge NFTs from Ethereum to ZKsync Era using OKX?OKX does not support NFT bridging at this time. Only fungible ERC-20 tokens listed in the bridge interface are eligible.

Q: Why does my bridged USDT show as “USDT.e” instead of standard USDT on ZKsync?This reflects the bridged version issued by OKX’s canonical contract on ZKsync Era—it maintains full 1:1 peg and interoperability with all ZKsync-native dApps.

Q: Is there a fee for withdrawing assets back from ZKsync Era to Ethereum via OKX?Yes. Each reverse bridge incurs both Ethereum gas fees and a fixed OKX service fee denominated in ETH, displayed before confirmation.

Q: What happens if I send tokens to ZKsync Era using a non-OKX bridge?Assets transferred via third-party bridges may land in different contract addresses and will not appear in your OKX wallet unless manually added and recognized by OKX’s token registry.