Arc mainnet launch: 16 September 2026
The chain is already running behind a closed door. This page sets out how it got here, what opens on the day and what does not, and the two commitments Circle has made for after launch. Dates are Circle's; the gate readings are ours.
| Date | Event |
|---|---|
| August 2025 | Arc unveiled by Circle |
| October 2025 | Public testnet opens, chain 5042002, with more than 100 institutions and builders named as participants |
| May 2026 | ARC whitepaper published. Private token presale reported at $222 million on a $3 billion fully diluted valuation |
| 12 May 2026 | Mainnet genesis. The published genesis in circlefin/arc-node carries this timestamp, and the chain has produced blocks since, behind a closed RPC. Circle describes more than 100 institutional and ecosystem builders testing on the private mainnet |
| 21 May 2026 | Arc House builder spotlight on Tower Exchange, the first ecosystem project given an official platform |
| 5 to 6 August 2026 | Founding validator set and the 16 September public launch date announced |
| 10 September 2026, 15:00 UTC | Zero7 and Zero8 hard forks activate on mainnet, per the arc-node changelog. Node operators must be on a supporting version before then. Zero8 already activated on the testnet on 3 September |
| 16 September 2026 | Public mainnet. Anyone can deploy contracts and transact. Circle says it will introduce an initial product suite: smart contract development tooling, tokenised real-world asset management, and ecosystem navigation resources |
| Second half of 2027 | DTCC tokenisation of DTC-custodied securities on Arc, per DTCC and Circle |
| By May 2028 | Committed transition of validation to proof of stake |
The chain is producing blocks. A small number of wallets hold USDC on it, bridged during a brief window when the network first came up or funded through Circle's own rails for private-mainnet builders. What the public cannot do is reach it: the official RPC and gateway are blocked, the explorer sits behind a sign-in wall, and Circle's attestation service does not complete public bridge messages to Arc's CCTP domain. The gate status strip tracks each of those doors by hand and will flip them as they open.
Because the doors are shut, the only public trace of activity on the chain comes from third-party scanners reading it through their own endpoints. The terminal shows those figures with a third-party mark and will check them against the chain once it can.
Permissionless deployment: any contract, any EVM wallet, no network-level KYC. The public RPC and explorer. The public bridge, which in practice means Circle's attestation service starting to complete CCTP messages to domain 26. Day-one integrations Circle has named, including Aave, Morpho and Uniswap, wallets such as MetaMask, Ledger, Binance Wallet and Kraken, and tokenised treasuries including BlackRock's BUIDL and Circle's USYC.
What does not open: the validator set, which stays permissioned until the proof-of-stake transition, and any retail tokenised equities, which are not part of the launch. The equity path Circle and DTCC have described is institutional and starts in 2027.
Circle's public node repository is a bot-synced copy of a private one. Its mainnet genesis is dated 12 May 2026, which is when the chain actually started, and its coinbase is the digits of pi by choice. The USDC contract's admin roles read as zero in that config, but a synced copy can lag the live chain, so the genesis watch shows the value without treating it as a launch signal. The reliable signals in the repository are its releases and changelog: the v0.8.0 notes set the Zero7/Zero8 activation on mainnet for 15:00 UTC on 10 September, six days before the public opening.
- Arc public mainnet launches 16 September 2026, Arc House, 6 August 2026 - launch date, permissionless deployment, product suite, private mainnet status
- Arc, Circle's official site - validator set and day-one ecosystem
- Circle pressroom - validator announcement, DTCC and proof-of-stake commitments
- circlefin/arc-node CHANGELOG - Zero7/Zero8 mainnet activation timestamp 1789052400
- circlefin/arc-node mainnet genesis - genesis timestamp 1778544000, 12 May 2026
Chain facts on this page come only from Circle. Where a figure is the site's own reading, the terminal card it comes from is linked. Definitions are on the method page.