> ## Documentation Index
> Fetch the complete documentation index at: https://turnkey-0e7c1f5b-renovate-npm-js-yaml-vulnerability.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Turnkey is wallet infrastructure: create and manage crypto wallets, sign transactions, and enforce policy-based access controls. Best-fit uses: embedded consumer wallets (email/passkey/social auth, no seed phrases), automated onchain operations with server-side wallets, AI agent wallets with policy-scoped signing, enterprise key management, and verifiable off-chain workloads on Turnkey Verifiable Cloud (TVC).
> Every API call is a JSON POST to https://api.turnkey.com signed with a P-256 API key; create an organization and key self-serve at https://app.turnkey.com.
> Key Turnkey developer resources: API reference (https://docs.turnkey.com/api-reference/overview/intro.md), OpenAPI spec (https://docs.turnkey.com/public_api.swagger.json), authentication (https://docs.turnkey.com/features/authentication/overview.md), webhooks (https://docs.turnkey.com/features/webhooks/overview.md), MCP server for docs search (https://docs.turnkey.com/mcp), agent skills (https://docs.turnkey.com/get-started/ai-skills.md), CLI (https://docs.turnkey.com/sdks/cli.md), SDK reference (https://docs.turnkey.com/sdks/introduction.md), full docs content (https://docs.turnkey.com/llms-full.txt).

# Arc support on Turnkey

export const SupportCallout = ({prompt = "Need help with your Turnkey integration?"}) => <>
    {prompt} Reach out through any of our{" "}
    <a href="/solutions/support/overview">support channels</a>.
  </>;

Arc is a stablecoin-native Layer-1 blockchain built by Circle, purpose-built for real-world financial applications. Arc uses USDC as its native gas token, achieves sub-second deterministic finality, and is fully EVM-compatible. More on [Arc here](https://docs.arc.io).

## Address derivation

Turnkey supports Arc address derivation with `ADDRESS_TYPE_ETHEREUM`. This address format is valid across the Arc network and is identical to standard EVM address derivation.

## Transaction construction and signing

Because Arc is EVM-compatible, existing Ethereum tooling works on Arc without modification:

* [@turnkey/ethers](https://github.com/tkhq/sdk/tree/main/packages/ethers): contains a `TurnkeySigner` which implements Ethers' `AbstractSigner` interface. See [Ethers docs](https://docs.ethers.org/v6/api/providers/abstract-signer/#AbstractSigner).
* [@turnkey/viem](https://github.com/tkhq/sdk/tree/main/packages/viem): contains a `createAccount` method to create a Turnkey-powered [custom account](https://viem.sh/docs/accounts/local) which [Viem](https://viem.sh/) can use seamlessly.

We have an example that demonstrates how to construct and broadcast an Arc transaction:

* [`examples/chain-integrations/with-arc`](https://github.com/tkhq/sdk/tree/main/examples/chain-integrations/with-arc): demonstrates constructing and broadcasting a native USDC transfer via an EIP-1559 (type 2) transaction on the Arc testnet.

## Transaction management and gas sponsorship

Turnkey's [Transaction Management](/features/transaction-management) handles the full lifecycle of Arc transactions — construction, broadcast, nonce management, and status monitoring.

### Gas sponsorship (fee abstraction)

Set `sponsor: true` to enable fee sponsorship — your users never need to hold USDC to pay gas. Turnkey covers fees on your behalf and passes costs through as a monthly line item.

<Note>
  To enable gas sponsorship, ensure it is activated in your Turnkey dashboard before setting `sponsor: true`.
</Note>

## Differences from standard EVM chains

A few Arc-specific behaviors are worth knowing when integrating with Turnkey:

* **USDC is the native gas token.** ETH is not the native asset on Arc, so accounts need a USDC balance to transact. Native USDC uses an 18-decimal interface (standard `msg.value` semantics), while the ERC-20 interface on the same balance uses 6 decimals. To display a native value as USDC, divide by 10<sup>12</sup>. Don't credit or record balances from the 6-decimal value: truncation at the 6-decimal boundary records less than was transferred.
* **Blob transactions (EIP-4844, type 3) are not supported.** Turnkey supports signing type 3 transactions on Ethereum, but Arc's mempool rejects them — use legacy, type 1, or type 2 transactions on Arc.

For the full list of protocol-level differences, see [Arc's EVM differences](https://docs.arc.io/arc/references/evm-differences).

## Transaction parsing, policies, and signing

Please refer to our [Ethereum network page](/features/networks/ethereum) for details on transaction parsing, policies, and signing, as Arc shares the same EVM architecture. Turnkey's EVM transaction parser, policy engine, and `SIGN_TRANSACTION` activity types all apply — including EIP-712 typed data signing.

## Arc network support

Turnkey supports:

| Network     | Chain ID  | RPC                                                                       |
| :---------- | :-------- | :------------------------------------------------------------------------ |
| Arc Mainnet | `5042`    | See [Arc RPC endpoints](https://docs.arc.io/arc/references/rpc-endpoints) |
| Arc Testnet | `5042002` | See [Arc RPC endpoints](https://docs.arc.io/arc/references/rpc-endpoints) |

## Benefits of using Turnkey with Arc

* **Secure key management**: Private keys are securely stored in Turnkey's enclave infrastructure
* **Policy controls**: Apply custom policies to authorize transactions based on destination, value, calldata, and more
* **Developer-friendly**: Integrate with existing EVM development workflows — ethers, viem, Foundry, Hardhat

<SupportCallout prompt="Building on Arc and need help with your Turnkey integration?" />