Cross-chain · Base → Arbitrum One

Swap WETH from Base to USDT on Arbitrum One

Swap WETH from Base to USDT on Arbitrum One. Base WETH leaves, and Tether USDT arrives on Arbitrum One, chain 42161.

The wrapper you approve is 0x4200000000000000000000000000000000000006 on Base, chain 8453, on Basescan. Gas for that step is ETH. The USDT you receive is 0xFd086bC7CD5C481DCC9C85ebE478A1C0b69FCbb9, 6 decimals, on Arbiscan. It is Tether, not Circle's native USDC at 0xaf88d065e77c8cC2239327C5EDb3A432268e5831 and not USDC.e. Ethereum Tether at 0xdAC17F958D2ee523a2206206994597C13D831ec7 is a mainnet contract. This destination is Arbitrum One, not Nova. Native gas is 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, and you are not delivering it.

Diagram for Swap WETH from Base to USDT on Arbitrum One — WETH leaves Base. USDT is what can arrive on Arbitrum One.

Selling the wrapper into Tether

You exit ETH exposure. You do not relocate WETH to 0x82aF49447D8a07e3bd95BD0d56f35241523fBab1. WETH has 18 decimals and this USDT has 6, so raw log integers are not comparable. Read the human amount. Tether can freeze addresses. A bridge from Base does not remove a freeze that already applies to your address on this contract.

Circle would be a different fill

If the counterparty redeems at Circle, native USDC on One is the contract to buy, and this page is wrong. If they named USDC.e, neither this USDT nor native USDC will match. If they named Ethereum USDT, chain 1, you still have another hop after this one. Chain 42161 is not chain 1, even though both use the letters ETH for gas.

Approval chain versus receive chain

Approve WETH on Base only. Do not approve USDT in order to receive it. A later One app may ask to spend USDT, and that request is paid with ETH on chain 42161. If the wallet is on Nova during that second signature, you are approving a different network. Check the badge.

Two explorers, no shared hash

How cross-chain bridges work is why Basescan and Arbiscan do not share a transaction id. There is no promised wait. Bring ETH to One before you move USDT. If you hold native ETH instead of WETH, this route sees an empty input. Decline a minimum you will not accept.

Legal

Risk disclosure

XAUConnect is a non-custodial swap aggregator. Digital assets are volatile and may lose value rapidly. Content on this page is educational and not investment advice. Verify every contract address on the official block explorer before approving a transaction.

Frequently asked questions

What is the best way to swap WETH from Base to USDT on Arbitrum One?

The wrapper you approve is 0x4200000000000000000000000000000000000006 on Base, chain 8453, on Basescan. Gas for that step is ETH.

Is this USDT the Ethereum Tether contract?

No. Ethereum Tether is 0xdAC17F958D2ee523a2206206994597C13D831ec7 on Etherscan. This route delivers 0xFd086bC7CD5C481DCC9C85ebE478A1C0b69FCbb9 on Arbitrum One, chain 42161, which you check on Arbiscan. Both use 6 decimals and both are Tether. A mainnet transfer will not move the One balance. Stay on Arbiscan and chain 42161 when you confirm Tether arrived.

Do I need WETH, or will native ETH work?

You need WETH at 0x4200000000000000000000000000000000000006. Native ETH on Base, the 0xEeee placeholder, pays gas and is not pulled as the sold asset. Wrap on chain 8453 first if the wrapper is what you meant to sell. An empty WETH balance cannot be approved into this trade.

Can the USDT pay Arbitrum fees?

No. Fees on chain 42161 are ETH, a separate balance from Base ETH. USDT cannot pay them. Nova will not show this credit even if you wait. Switch to Arbitrum One, fund ETH there, and only then can the Tether balance move. Base ETH never becomes that One gas balance.

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Open the swap page with this cross-chain route pre-selected, then connect your wallet on the source chain to quote and execute. You keep the keys.

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