How to Add Arc to MetaMask: Chain ID, RPC and Setup

Arc is EVM-compatible, so adding it to MetaMask is the ordinary custom-network flow: five fields, one save, done. The only Arc-specific detail is the currency symbol — the network's fee token is USDC, not a bespoke gas coin.

Works on Arc testnet today; mainnet September 16, 2026.

What are the Arc network parameters?

These are the public testnet values, verified against docs.arc.network in August 2026.

Mainnet parameters are not published yet. Circle opens public mainnet on September 16, 2026 and will publish the mainnet chain ID, RPC endpoint and explorer host at that point. This page will carry them the day they exist. Until then, treat any site advertising an "Arc mainnet RPC" as unverified — there is nothing legitimate to copy.

How do you add Arc to MetaMask manually?

1. Open MetaMask and click the network selector at the top-left of the extension.
2. Choose Add a custom network (older builds: Settings → Networks → Add network → Add a network manually).
3. Enter the six fields from the table above. The currency symbol is USDC; MetaMask may warn that the symbol does not match its records for the chain ID, which is expected for a new network.
4. Save, then switch to Arc Testnet in the network selector.
5. Confirm the connection by opening the explorer and pasting your address — if the balance MetaMask shows matches what testnet.arcscan.app shows, the RPC is connected correctly.

[SCREENSHOT: MetaMask "Add a custom network" form with the Arc testnet values filled in]

Why does the currency symbol say USDC?

Because on Arc it genuinely is. Gas is charged in USDC at 18 decimals at the protocol level, and testnet transactions have averaged roughly $0.004 each. There is no separate native coin to buy before you can transact, which is the single biggest practical difference between Arc and every other EVM chain you have added to a wallet. The full explanation of Arc's fee model is here.

One consequence worth internalising: the balance that pays your gas is the same balance you are spending. On other chains you can be rich in the token and stuck because you have no gas. On Arc, if you have dollars, you can transact.

How do you get testnet USDC?

Use Circle's faucet at faucet.circle.com and select Arc testnet. The faucet drips test USDC to the address you paste in; there is no purchase step and no bridge required for testnet funds. The testnet guide covers the faucet and a first transaction end to end.

For real USDC on mainnet after September 16, you will bridge with Circle's CCTP rather than a third-party bridge — how that works.

Which other wallets support Arc?

Any wallet that accepts a custom EVM network can be pointed at Arc using the same values. Circle has named MetaMask, Ledger, Fireblocks and Binance Wallet among day-one ecosystem partners, alongside Kraken and Upbit on the venue side. The setup flow differs cosmetically between wallets but the six fields are the same everywhere.

For hardware wallets, add the network in the software wallet first (MetaMask, for example), then connect the Ledger through it — the device signs EVM transactions generically and does not need Arc-specific firmware.

Common problems and what they actually mean

• "Could not fetch chain ID." The RPC URL is wrong or truncated. Re-paste https://rpc.testnet.arc.io in full, including the scheme.
• "This chain ID is already in use." You added Arc previously under a different name. Edit the existing entry rather than creating a duplicate.
• Symbol mismatch warning. Expected. MetaMask cross-references a public chain registry and Arc's USDC-as-gas model is unusual; the warning is informational.
• Balance shows zero after a faucet drip. Give the faucet a moment, then refresh. If the explorer shows the balance and MetaMask does not, the wallet is querying a stale RPC — switch networks and back.

Before you deploy anything

Once the network is added, the rest of the launch sequence is ordinary EVM work. Team Finance is ready for Arc on day one: mint a token, lock the liquidity, put the team allocation under a schedule and distribute. It has been non-custodial since 2020 and has secured more than $2.7 billion across 40,000+ projects on 26 chains.

The order that matters to buyers is: mint, lock liquidity, vest the team, then prove all three on the explorer.