Circle Tightens CCTP V1 Burn Limits Starting Oct. 31

Circle will begin reducing burn limits on its legacy Cross-Chain Transfer Protocol starting Oct. 31, 2026, forcing applications still relying on CCTP V1 to migrate to the new V2 standard before the company pauses V1 contracts entirely on Dec. 1.

The deprecation follows Circle’s November 2025 announcement of the move away from V1. The company published a detailed October-to-December timetable on Aug. 27, 2026, outlining the phase-out schedule. Beginning Oct. 31, burn limits will progressively tighten, capping how much USDC can enter the cross-chain transfer process at any given time. Circle’s migration guide describes the limits narrowing until no new burns can be initiated, with transfer volume intended to reach zero before the full pause takes effect.

How CCTP Works and Why Migration Matters

CCTP transfers USDC by burning it on a source blockchain and minting it on the destination blockchain. Circle’s signed attestations approve burned USDC to be minted on the destination chain. The burn limit caps how much can enter that process at once.

CCTP V2 is incompatible with V1 integrations. Applications must update contract calls and APIs to continue operating. The new protocol introduces two core contract interfaces: TokenMessengerV2 and MessageTransmitterV2. The depositForBurn function in TokenMessengerV2 adds three new parameters: permitted destination caller, maximum fee, and minimum finality threshold.

Attestation Workflow Changes

The attestation process undergoes substantial revision. In V1, integrations extract message bytes and hash them. V2 eliminates that step. Integrations can instead use the V2 messages endpoint with the transaction hash, streamlining the approval flow.

CCTP V2 offers two transfer modes: Standard and Fast Transfer. Fast Transfer carries a variable fee based on the source chain. The replaceDepositForBurn function, available in V1, does not carry over to V2.

Pending Redemptions and Contract Pause

Pending redemptions will remain available during the phase-out period. Circle will maintain minting allowances above the total of pending attestations, ensuring redemptions can be processed before the full Dec. 1 pause. After that date, V1 contracts will be paused entirely.

Circle offers optional migration tooling through Arc App Kits to assist applications in transitioning to V2. The company published its migration guide alongside the timetable to provide technical detail on contract updates and API changes required for the transition.