Circle’s Arc: Stablecoin Evolution

Circle, known for its

USDC

stablecoin, has
introduced
a novel

blockchain

platform: Arc. Unlike broader blockchain ecosystems like
Ethereum
or
Solana, Arc operates as a Layer-1 network specifically engineered for stablecoin applications.

Stablecoins
,
digital assets linked to the value of traditional currencies, are the core focus. Circle envisions Arc as a solution to infrastructure limitations that hinder stablecoin adoption at a large, institutional level.

Rachel Mayer, VP of Product Management at Circle, shared with *Decrypt*, “We’ve supported enterprise and builder adoption of USDC across a range of different networks. The consistent message we heard back was: provide cost certainty, ensure definitive settlements, and make privacy compatible with real-world compliance obligations.”

This article will explore Arc, detailing its functionalities and Circle’s explanation of its distinctions within the broader blockchain landscape.

The Genesis of Arc: Circle’s Motivation

Stablecoins, including
USDT
and
USDC, have witnessed considerable growth, amplified by the enactment of the
GENIUS Act, signed into law in July 2025.

However, Circle believes the architecture of most blockchains is unsuited to fully supporting stablecoins. Circle highlights the following limitations:

• 🎢 Unstable transaction fees
• ⛓️ Settlement uncertainty with the potential for blockchain reorganizations
• 🕵️ Deficient privacy tools for sensitive business exchanges
• 💧 Divided liquidity across multiple blockchains

Circle states that Arc overcomes these difficulties by providing settlement that is both instantaneous and irreversible, predictable charges specified in stablecoins, optional privacy features for regulatory adherence, and connections to both traditional financial networks and alternative blockchains.

The Arc roll out will occur in three phases:

• Private testnet launched in August 2025
• Public testnet expected in Fall 2025
• Mainnet beta planned for 2026

USDC as the Core Fuel

By using
USDC, Circle seeks to circumvent the necessity of volatile assets to pay for transactions. The network will support other stablecoins to pay for gas via a paymaster system.

Circle states that Arc’s fee structure is built upon Ethereum’s
EIP-1559
but trades block-level adjustments for a weighted moving average of demand. This smoothing effect helps to ensure steady and low fees. These fees are denominated in USDC, and go to an on-chain Arc Treasury.

“Arc’s rapid finality and native gas together with Circle’s CCTP and Gateway interoperability, allows USDC to move through blockchains,” Mayer stated. “So builders and users can operate on their ideal networks while also benefitting from Arc’s optimized stablecoin rails.”

This framework creates auditable fee models with dollar-denominated stability, which Circle says will appeal to financial institutions more than token models.

Consensus and Settlement Certainty

Arc uses Malachite, a Byzantine Fault Tolerant (BFT) engine anchored in Tendermint, as its consensus layer. Right now, validator selection is permissioned based on compliance, resilience, and distribution. However, Circle has shared that its plans include shifting to Proof-of-Stake system.

In order to reduce the risk of abuse, Circle is building encrypted
mempools,
transaction batching, and consensus by multiple proposers, which are all meant to ensure a fairer environment for financial applications.

Selectable Privacy for Organizations

Arc integrates a privacy system that intends to strike a balance between compliance and privacy. The initial feature, called confidential transfers, obscures transaction amounts while addresses remain public. Smart contracts work with a cryptographic backend by utilizing precompiles, making use of Trusted Execution Environments (TEEs) for private computations.

Organizations can give specific data to regulators and auditors by using keys. Arc also intends to include these options in the future:

• Private state with confidential computation
• Zero-knowledge proofs
  (ZKPs)
• Multi-party computation (MPC)
• Fully homomorphic encryption (FHE)

Circle’s technologies connect fiat and USDC through Arc and various blockchains: Mint converts fiat to USDC on Arc, CCTP transfers USDC across chains, and Gateway gives access to chain-agnostic balances with liquidity management capabilities for applications.

“Arc can unlock new adoption by institutions,” stated Mayer. “Builders and users can use networks that suit their requirements, and still use the Arc stablecoin.”

The Arc in the Blockchain

The Arc enters a competitive arena that includes public Layer-1 blockchains like Bitcoin, Ethereum, and Solana, blockchains centered on stablecoins such as
Plasma
and
Frontier,
Layer-2 networks like Arbitrum and Base, and private networks managed by payment companies.

Circle separates itself from competitors with its reputation as the issuer of the USDC.

By creating a dedicated chain for financial transactions, Arc aims to broaden stablecoin utility beyond payments into tokenization and global capital.

“Regulatory clarity drives institutional adoption,” Mayer concluded, “and Arc is enterprise-grade.”