Crypto
Home›Crypto›Market Structure›Circle starts winding down CCTP V1 USDC cross-chain tr…
Circle starts winding down CCTP V1 USDC cross-chain transfers
Circle says V1 burn limits begin falling Oct. 31, then legacy contracts pause Dec. 1, leaving any integration still routed to V1 unable to move USDC across chains.
Circle’s Cross-Chain Transfer Protocol V1 deprecation creates a migration deadline for developers moving USDC across blockchain networks. Circle said integrations using the first version of CCTP get 95 days to migrate before the legacy contracts stop processing USDC transfers, with the cutoff tied to cross-chain routing.
Circle said CCTP V1 burn limits start falling on Oct. 31. Those limits and transfer capacity will be reduced through November, and Circle plans to pause the V1 contracts on Dec. 1, at which point any integration still pointing to V1 will no longer move USDC across chains. The company added that users should retain access to funds during the phase-out and that pending redemptions will remain available.
Circle described key mechanics of the migration, including that an attestation is Circle’s signed approval for USDC burned on a source chain to be minted on a destination chain. Circle said it will keep enough minting capacity to complete outstanding attestations before V1 is fully paused, and that integrators must update code because CCTP V2, now branded as CCTP, is incompatible with V1.
Circle said CCTP V2 uses different contract addresses, interfaces, and APIs, requiring integrators to point to the V2 versions of TokenMessenger, MessageTransmitter, and TokenMinter and change calls such as depositForBurn. It also said the V2 function adds parameters including a permitted destination caller, maximum fee, and minimum finality threshold, plus it calls for replacing legacy attestation calls with a /v2/messages/{sourceDomainId} flow and handling applicable fees.
Circle’s documentation notes that native routes to or from certain networks still depend on the legacy network unless a separately documented alternative is used. In its supported-chain matrix, Aptos is listed among chains supported only by CCTP V1, alongside Noble and Sui, and Circle said it has not identified which exchanges, wallets, bridges, or apps continue to call the old contracts.