What's actually live on Arc mainnet

Arc mainnet went live on 16 September 2026. The chain itself is live; every project, partner and validator below is recorded at the status we could observe, on the date shown. This page is a status log, not a forecast.

This guide exists because "Arc is live" and "this project is live on Arc" get conflated constantly in ecosystem coverage, and the distinction matters for anyone deciding whether to build, deploy funds, or route payments through the chain. Below is a section-by-section accounting of the network itself, its validator set, and the ecosystem around it, each held to the same four-value status system used across this directory.

The chain itself

Status: Live on Arc — mainnet chain ID 5042, RPC https://rpc.mainnet.arc.io, explorer https://explorer.arc.io, per docs.arc.io, 16 September 2026.

Arc's public testnet launched 28 October 2025 and keeps running on chain ID 5042002 with RPC at rpc.testnet.arc.io, a block explorer at testnet.arcscan.app and a faucet at faucet.circle.com. Take the mainnet RPC and explorer only from docs.arc.io; anything else is unverified. Gas on Arc is denominated in USDC at 18 decimals with an EIP-1559-style base fee, and the chain is EVM-compatible, meaning standard tooling — Solidity, MetaMask, ethers.js — works without modification on mainnet, per Circle's docs. Consensus runs on Malachite, a Tendermint-based BFT engine Circle says targets sub-second (roughly 780ms) finality, with a 1MB block size cap.

The validator set

Status: Announced — mainnet live since 16 Sep 2026; validator activity not yet independently observed.

Circle named eleven founding validators in an 5 August 2026 press release: BlackRock, DTCC, Galaxy, Global Payments, ICE, Mastercard, MoneyGram, SBI Group, Standard Chartered, Sumitomo Corporation, and Visa. Circle itself also operates the network. This is a permissioned validator set — named institutions run consensus, not an open or permissionless set anyone can join. Circle says these eleven hold consensus seats from mainnet launch; Built on Arc has not yet independently observed each one producing blocks on explorer.arc.io. Each institution's own primary role (mostly Integrates, per the canonical role map) is separate from the validator mark. The full detail, including what "permissioned" does and doesn't imply, is in Arc's founding validators, explained.

Named integration partners

Status: Announced, spanning testnet participation to no public deployment.

The same 5 August release named a long list of integration partners across categories: BNY (exploring integrations) and DTCC on tokenization; DeFi and capital-markets protocols including Aave, Aerodrome, FalconX, Galaxy, GSR, Keyrock, Morpho, Nonco, Uniswap Labs, and XFX; stablecoin payments routing partners Rain, Thunes, and Wirex; and exchange and wallet-custody partners Binance Wallet, Chainlink, Fireblocks, Kraken, Ledger, MetaMask, and Upbit. Several of these — Aave, Aerodrome, Morpho, and Uniswap in particular — are yield and DEX protocols; Built on Arc tracks their Arc status at DeFi & Credit on Arc and Exchanges & Trading on Arc, but not their earn angle, rates or returns. Naming in a press release is not the same as a live integration; the full named list, grouped by function, is in Arc mainnet launch partners: the full list.

Separately, individual fintechs have confirmed narrower testnet participation ahead of the same release — PhotonPay (a Hong Kong payments processor) said in November 2025 it had joined Arc's testnet, and Brazil's BTG Pactual was named among banks and asset managers that joined Arc's public testnet at its October 2025 launch. Both remain Testnet as of 2 September 2026.

Web3-native applications

Status: Overwhelmingly announced or testnet; no confirmed mainnet deployments.

Launchpad and DEX projects positioning themselves for Arc — TowerExchange, Radar DEX, AstraPump, Lunex, Hinkal, ARCLaunch, uarc.me, and ArcSwap among them — are, as a group, unobserved on mainnet as of the check date. Lunex, a Curve-style stablecoin AMM, has reported testnet TVL around $1.29 million and cumulative volume near $2.59 million, both testnet figures rather than mainnet activity. Hinkal, a privacy and confidential-settlement protocol, announced testnet deployment in March 2026. Several names in this category — ARCLaunch in particular — carry a heavy volume of syndicated press coverage relative to any verifiable shipped product; treat marketing volume and shipped status as two different things. None of this class has a confirmed mainnet presence as of 2 September 2026.

The Circle Developer Grants cohort

Status: Real, pre-Arc production businesses; Arc integration mostly announced or in progress.

The startups funded through Circle's Developer Grants program — Blockradar, Hurupay (now Kolan), Myaza, Arrel Technology, Payrit, ViFi Labs, SFx Money, and Flezpay — are, unlike most Class A projects, operating real payment businesses today, largely off the chain entirely or on Arc's testnet. None of them had been observed live on Arc mainnet as of the check date. Full detail on this cohort is in Circle's Arc grant recipients, confirmed.

Third-party tooling documented for Arc

Independent of Circle's own materials, at least two RPC providers have published working documentation for Arc's testnet as of 2 September 2026: QuickNode, at quicknode.com/docs/arc, and GetBlock, at docs.getblock.io/api-reference/arc. Circle's connect-to-arc reference now lists mainnet endpoints for Alchemy, Blockdaemon, dRPC and QuickNode; whether each provider's own documentation has been updated to match is a separate check. Builders evaluating RPC options for Arc should verify directly with each provider which network — mainnet or testnet — their published docs actually cover, rather than assuming testnet-documented support extends automatically.

What changed on 16 September, and how this page updates

At mainnet launch, the sections above flipped in place rather than being rewritten: the chain-itself section moved from "Testnet" to "Live on Arc" once Circle published the mainnet RPC, explorer and chain ID; the validator section updates once validators are confirmed actively signing blocks; and each named partner or project moves individually as we confirm its own mainnet deployment — a press release naming a partner is not sufficient on its own. Expect this page to change through late September 2026, and expect some announced partnerships not to materialize at all; that is normal for a days-old ecosystem and this page will say so plainly when it happens.

Sources: - Circle Announces Founding Validator Cohort and Major Integrations for Arc - Circle Launches Arc Public Testnet - PhotonPay Is the Latest to Join Circle's New Arc Blockchain - Circle lança blockchain de stablecoins com participação de banco brasileiro