Circle's Arc mainnet went live on Wednesday, a milestone that CEO Jeremy Allaire described as "the single most significant launch in Circle's history since USDC itself."

The new Layer 1 blockchain is built for stablecoin payments, trading and agentic transactions — activity carried out by autonomous AI software agents — with USDC, Circle's dollar-pegged stablecoin, serving as its native gas token. USDC currently has around $74 billion in circulation, and paying network fees in a stablecoin rather than a separate, more volatile token sets Arc apart from most Layer 1 blockchains, where transaction costs are denominated in native tokens that fluctuate in price.

LATEST: ⚡️ Circle launched the Arc mainnet, its new L1 blockchain designed for financial markets and the AI agent economy, with BlackRock, Visa, Mastercard, and the DTCC serving as founding validators. pic.twitter.com/m4hI9MDBnc — CoinMarketCap (@CoinMarketCap) September 16, 2026

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According to Circle's announcement, the chain is EVM-compatible — meaning applications built for Ethereum can run on it with minimal changes — and offers deterministic sub-second settlement finality, a combination intended to attract developers and institutions seeking fast, stablecoin-native infrastructure. For Circle, the launch also extends its role beyond issuing stablecoins to running the underlying settlement infrastructure itself.

Arc debuted with more than 100 institutional and ecosystem partners on day one. Its founding validators include BlackRock, the Depository Trust & Clearing Corporation (DTCC), ICE, Mastercard, Visa, Standard Chartered, MoneyGram, SBI Group, Sumitomo, Worldpay and Galaxy — a roster spanning asset management, market infrastructure, card networks, banking and payments. Validators are the operators responsible for processing and confirming a blockchain's transactions.

The validator set is permissioned, unlike most public blockchains where anyone meeting technical requirements can participate. Circle frames this as a feature, saying it gives banks a defined governance structure for using a public chain for treasury operations, trading and confidential payments.

Who Has Access

BNY, HSBC, Societe Generale and State Street are among the banks with access to Arc. On the DeFi side, Aave and Morpho handle lending, while Uniswap, Aero and FOMO provide trading venues. Exchanges including Binance, Kraken, Bybit and OKX offer entry points into the network, with Coinbase set to follow.

BlackRock's BUIDL fund and Circle's own USYC token provide tokenized collateral on the chain — onchain representations of traditional assets that can be pledged in place of cash.

Arc supports more than 20 fiat stablecoins, including USDC, EURC, JPYC, KRW1 and TRYB, and connects to more than 20 other blockchains through Circle's Cross-Chain Transfer Protocol (CCTP) and Gateway.

USDC accounts for 98.8% of agent-driven transaction volume on the network, according to Circle, citing Dune analytics data.

ARC Token

Circle completed the genesis mint of 10 billion ARC tokens this week, a step the company said makes it the first publicly traded firm to mint a network token for a new Layer 1. Circle was nonetheless explicit that the mint "is not a commitment to publicly launch ARC."

The mint is described as a technical step toward a potential transition from Proof of Authority to Proof of Stake consensus in 2027. Circle had previously raised $222 million in an Arc token presale at a $3 billion valuation.

Arc's public testnet launched in October 2025, with BlackRock and Visa among the early participants, and processed more than 700 million transactions in under a year. More than 100 companies took part in Arc's private mainnet ahead of Wednesday's public launch.

Out of the box, Arc ships with agent wallets, spending limits and nanopayments built in. The network also supports optional post-quantum signatures — cryptographic safeguards designed to resist attacks from future quantum computers — with broader protections still in development. With the public launch now behind it, the next milestones to watch are Coinbase's pending integration and the potential shift from Proof of Authority to Proof of Stake in 2027.