arbitrum, the fifth network
Arbitrum is the fifth network, with two stablecoins: USDC, issued natively by Circle, and USD₮0, Tether's official omnichain USDT. Tether doesn't issue classic USDT on Arbitrum; the USDT contract there became USD₮0 in place, so it's one contract and no duplicate. we label it USD₮0 and count it as USDT in your balance.
both are gasless from day one: transfers are signed authorizations, we pay the ETH, and the transfer and the fee land in one transaction. for API customers Arbitrum went live on august 19, with hotwallets, child addresses, sweeps and withdrawals; per sweep or withdrawal our fee is $0.10 on free and $0.05 on pro, and the gas is on us. in the app, Arbitrum arrived with version 1.0.2, on the same 0x address you already use for Base.
one evm address in the api
in the API, one EVM address now covers Base and Arbitrum. create an EVM hotwallet and you get one key, one wallet_secret and the same 0x address on both networks. child addresses work the same way: one address receives USDC on Base and USDC or USD₮0 on Arbitrum, under the same external_ref.
if you already had a Base hotwallet, creating the Arbitrum one mirrors it and its child addresses, with no new secret; the one you have keeps working. a pair counts as one address toward your plan's watched-address limit. receiving is unified, moving money is still per network, so sweeps and withdrawals name the network they run on. the panel shows the pair as a single EVM block.
fixes and improvements
- POST /v1/address/validate accepts base and arbitrum.