Cross-Chain Transfer Protocol (CCTP)

The Cross-Chain Transfer Protocol (CCTP) lets USDC move between supported chains without wrapped tokens. A user or app burns USDC on the source chain, Circle's attestation service observes the burn and signs a message, and that signature authorises the USDC contract on the destination chain to mint the same amount. Apps and bridges integrate it so the process is invisible to users.

CCTP ended much of the confusion between native USDC and bridged variants such as USDC.e, which had different risks and liquidity on each chain. Its second version, launched in 2025, added fast transfers that complete in seconds by relying on Circle to cover the gap before source-chain finality, and hooks that let the destination run actions automatically after minting. Circle then made V2 the canonical version and in 2026 began retiring the original, renamed V1 (Legacy).

The trust model is simple: users rely on Circle, which already controls USDC issuance and can freeze addresses. If its attestation service stalls, transfers pause, and only chains Circle has added are reachable. CCTP is not a general bridge either; it moves USDC and, where supported, Circle's other tokens.