CCTP (cctp)

​

When to use it

• Move USDC to another chain as native USDC, with Circle’s attestation as the only trust.
• Only the burn happens in the program’s transaction. The mint is a separate transaction on the destination, sent by anyone with the attestation.

​

Pitfalls for a program

• Approve the TokenMessenger for the amount first.
• destinationDomain is Circle’s domain id, not the chain id: each chain’s file in chains gives its CCTP domain.
• mintRecipient and destinationCaller are 32-byte words: an EVM address fits as is, and a destinationCaller of 0 lets anyone complete the mint.
• minFinalityThreshold 2000 waits for standard finality; 1000 asks for a fast transfer, for which maxFee (in USDC units, taken on the destination) must cover Circle’s fee.

​

In a Sauce program

function main(amount: Uint256, recipient: Address, maxFee: Uint256) {
  // Arbitrum is CCTP domain 3; 2000 is standard finality (1000 asks for a fast transfer).
  USDC.approve(Cctp.TokenMessenger, amount);
  Cctp.TokenMessenger.depositForBurn(amount, 3, recipient, USDC, 0, maxFee, 2000);
}

function main(amount: Uint256, recipient: Address, maxFee: Uint256) {
  // Arc is CCTP domain 26; on a testnet the same id reaches Arc Testnet.
  USDC.approve(Cctp.TokenMessenger, amount);
  Cctp.TokenMessenger.depositForBurn(amount, 26, recipient, USDC, 0, maxFee, 2000);
}

​

Notes

• Domains are Circle’s numbering; the registry records them per chain.
• On a testnet (Arc Testnet, Base Sepolia, Ethereum Sepolia) the TokenMessenger is Circle’s testnet contract, not the mainnet one, and the domain is the mainnet’s (Arc Testnet 26, Base Sepolia 6, Ethereum Sepolia 0). Cctp.TokenMessenger resolves to the chain’s own; its attestation comes from Circle’s sandbox API, https://iris-api-sandbox.circle.com.

​

Its names in a program

function main() {
  // Ethereum's tokenMessenger, `0x28b5a0e9C621a5BadaA536219b3a228C8168cf5d`.
  require(Cctp.TokenMessenger != 0);
}

​

Deployments

​

ABI

​

TokenMessengerABI

• depositForBurn(uint256 amount, uint32 destinationDomain, bytes32 mintRecipient, address burnToken, bytes32 destinationCaller, uint256 maxFee, uint32 minFinalityThreshold)

​

Next steps

• Protocols: the other protocols, by what they do.
• Protocols and tokens: calling a contract by its namespace, or through its ABI.
• Glossary: the words these pages use, in plain terms.