Circle Expands Cross-Chain Transfer Protocol
Circle has broadened the capabilities of its Cross-Chain Transfer Protocol (CCTP), now accommodating not just USDC but also the newly integrated native EURC and cirBTC assets. This expansion includes enhancements to its Gateway and Bridge Kit functionalities to support a wider range of multi-asset operations.
Interoperability Features and Updates
Following an update on September 23, Circle’s Arc platform announced that interoperability features are now fully operational, with CCTP, Gateway, and Forwarding Service incorporated into the Layer 1 architecture. This integration offers developers distinct tools tailored for Circle-issued assets, tokens from other sources, and emerging multichain assets, as well as streamlined balance management.
It is important to note that while the CCTP has been activated for EURC and cirBTC, not all Circle services currently support these new assets uniformly. At present, CCTP allows transfers of USDC, EURC, and cirBTC along specific routes, although the Gateway feature will initially support only USDC. Circle has indicated plans to roll out support for EURC and cirBTC through the Gateway feature in the near future.
Core Functionality of CCTP
CCTP’s core functionality allows for 1:1 transfers of native assets across different blockchain networks. The protocol operates by burning tokens on the source blockchain and minting equivalent tokens on the recipient network, thus bypassing the liquidity pools typically required by traditional bridging systems. EURC was introduced to this ecosystem earlier in September, with its initial transfer routes established between Ethereum and Base. Recent updates have now extended EURC’s availability to other networks including Arc, Avalanche, and World Chain.
In a similar fashion, cirBTC was integrated into Arc on September 21, enabling cross-chain transactions for this BTC-backed token between Arc and Ethereum. Each cirBTC is backed 1:1 by actual BTC reserves, verified on-chain, with Circle International Bermuda Limited responsible for its issuance under a Class F Digital Asset Business license from the Bermuda Monetary Authority.
New Services and Transactional Capabilities
Circle also launched a service allowing Bitcoin-backed USDC borrowing via cirBTC, enabling qualifying Circle Mint institutions to use cirBTC in third-party lending markets to receive USDC. The initial lending protocol to support this service was Morpho.
The transactional capabilities for these three assets, however, vary significantly. USDC remains the most versatile asset within the CCTP framework, leveraging all available routes in Arc’s interoperability suite. In contrast, EURC supports a broader array of networks than cirBTC, which is currently confined to Arc and Ethereum.
According to Circle, transferring assets across supported Arc routes can now be accomplished in under ten seconds, although they advise users that these times may vary based on specific network conditions. To improve the user experience, the Forwarding Service allows the automated relay of destination-chain transactions, meaning users do not have to hold the destination chain’s gas tokens separately.
Future Developments and Regulatory Compliance
In a recent CCTP update, Circle introduced prepaid Fast Transfer fees, enabling developers to determine and communicate expected fees on the source network before asset transfers occur. Pricing for transfers via Arc will vary, with Circle not establishing a fixed fee for transactions involving USDC, EURC, and cirBTC.
Circle’s Gateway, primarily designed for USDC, is expected to support unified balances from assets traversing different networks, although support for EURC and cirBTC is still forthcoming with no specific timeline given. Currently, the Gateway operates under a non-custodial framework and has not undergone regulatory review by the New York State Department of Financial Services or any other authority.
Throughout recent months, Circle has been actively developing its multi-asset interoperability framework. An April roadmap indicated that CCTP had already facilitated over $140 billion in USDC transfers across more than 20 chains, with plans to extend similar functionalities to EURC and cirBTC.
The September 23 announcement marks a significant step in realizing that roadmap, even as the completion of Gateway’s asset support remains an ongoing process. Furthermore, Circle’s interoperability offerings are not limited to its own tokens; they also comprise third-party assets through the Crosschain Token Standard (CTS), supporting various necessary controls for developers and token issuers.
As Circle explores further enhancements, including a transition to Proof of Stake by 2027, it remains committed to expanding its interoperability and cross-chain capabilities while ensuring regulatory compliance. The company minted an initial supply of 10 billion ARC tokens for the project that should not be misconstrued as a commitment to launch an exchangeable currency at this stage.
Pending developments for Gateway’s support of EURC and cirBTC are among the next milestones in Circle’s evolving interoperability journey.
