Overview

Circle is the issuer of the USDC stablecoin. The Circle integration with Fireblocks allows you to purchase USDC issued directly from Circle and transfer it from your Fireblocks workspace.

This article describes the steps to connect your Circle account to your Fireblocks workspace. After connecting your Circle account, you can securely transfer or hold digital assets and perform the following actions:

Transfer USDC to or from your Circle accounts
Transfer USDC to or from other exchange accounts
Transfer USDC to third-party deposit addresses and Fireblocks Network members
Securely hold USDC in your Fireblocks Vault

Supported assets

The following assets are supported by Fireblocks for connected Circle accounts.

USDC on these blockchain networks:
- Ethereum
- Algorand
- Solana
- Avalanche
- Stellar
- Tron
- Polygon
EUROC - Only supported on Ethereum
USD - Support via wire transfer

Configuring your Circle account

To configure your Circle account to connect to Fireblocks:

Verify whether your Circle license agreement has API integration. If not, reach out to the Circle support team and request that they add it.
In your Circle dashboard, create an API key to use for your Fireblocks integration.
- This should be a Core API key for read-write and read-only operations.
- This API key should accept traffic from the following Fireblocks IP addresses for international exchanges: 52.76.208.129.
One business day later, Circle will send you an email with a login link. Log in using your email to get your API key.
Copy and keep your API key. You will need it to add this exchange to your workspace.

Info

You need to verify whether this exchange implements a time-period block for new addresses. If so, it may affect your ability to withdraw using the Fireblocks platform until after that period.

Configuring Fireblocks

Go to Accounts > Exchanges.
Select + Connect Account.
Select Circle, and then complete the following fields:

1. Name on Fireblocks: Enter the name you want to give this exchange account on Fireblocks.
2. Secret: Enter the API key that you saved from Circle. Note that the key is prefixed by "PROD_API_KEY", followed by the actual key, so you should enter the prefix as well. For example: “PROD_API_KEY:xxxxxxxxxxxxxxxxxxxxxx”.
3. Select Connect Account.

Note:

The "+ Connect Account" is relevant only if you have an existent exchange account connected to Fireblocks and would like to add another one. If this is your first exchange account connection, add it by selecting "Connect Account" under the Exchanges tab.

The Admin Quorum must approve the new account to make it available for new transfers from your workspace.

Your Circle account appears on the Exchanges page along with all managed assets and their balances. Following Admin Quorum approval, transfers are available from your vault accounts, whitelisted addresses, Fireblocks Network connections, and other connected exchange accounts to your Circle account.

Enabling withdrawals from Circle

To enable exchange account withdrawals, see this procedure.

Transferring assets

You can transfer your USDC assets to or from your Circle accounts, as well as transfer USDC between vault accounts, other exchanges, Fireblocks Network members, and whitelisted addresses.

There are two ways to transfer your Circle assets:

Using the Transfer button: Hover over the top-left corner, and select +Transfer.
Using the Withdraw or Deposit buttons: Under Exchanges > Circle, select Withdraw or Deposit to initiate a transfer.

Testing Circle on a test environment

In order to test Circle on the Fireblocks Test environment, you need to create a user on Circle's Sandbox here. To clarify: we do NOT use the Circle Testnet environment for testing, but rather the Sandbox environment.