Circle will begin winding down CCTP V1 on Oct. 31, 2026, with a gradual reduction in transfer capacity and a pause on Dec. 1 for new activity, while legacy contracts face progressively lower limits.

Starting Oct. 31, 2026, CCTP V1 burn limits will be reduced and, over time, no new burns can be initiated as part of the phased shutdown.

Arc App Kits provide an optional route to simplify migration by abstracting routine contract-addressing, interfaces, and attestation work.

CCTP V2 introduces new interfaces and addresses, such as TokenMessengerV2 and MessageTransmitterV2, and updates the attestation workflow with a dedicated V2 messages endpoint for retrieving messages and attestations.

V2 offers Fast Transfer and Standard Transfer modes, with programmable hooks for destination-chain actions and variable fees for Fast Transfer; some V1 functions, like replaceDepositForBurn, are removed.

After the Dec. 1 pause, integrations still targeting CCTP V1 will stop transferring USDC across blockchains, though pending redemptions will remain available and minting allowances will stay above pending attestations to process them.

Applications using CCTP V1 must migrate to CCTP V2, as V2 is incompatible with legacy integrations and requires changes to contracts and APIs.

Circle’s migration guidance outlines a staged phase-out designed to preserve minting capacity for pending redemptions while progressively limiting new burn activity before the full Dec. 1, 2026 pause.