Setting Up Account Linking via Mastercard Data Connect

This guide explains how to create and manage links to external accounts using Mastercard Data Connect. Before working with Galileo to set up account linking, see the Account Linking via Mastercard Data Connect guide for general information on the user experience and use cases.

Result of setting up account linking

Account holders can use your interface to link an external account that they own to their account they hold with you.

Prerequisites

• You must integrate with the Mastercard Data Connect (Full or Lite) SDK. Refer to Mastercard's SDK documentation for details.
• Galileo must perform some setup steps on the back end to enable this feature to work with your system.
• If you are currently using Galileo for ACH, you will need to work with Galileo to have your system call the new account linking endpoints instead of ACH endpoints.

Workflow

These are the entities involved in setting up Account Linking via Mastercard Data Connect:

• Account holder — Your customer, who has at least one account on your platform
• Your system — Your mobile app or web page, which has a control to launch the account linking process
• Galileo — The Galileo system
• Link provider — Interfaces with the external bank. For Account Linking via Mastercard Data Connect, the link provider is Mastercard.
• External bank — Houses the account holder's external bank account

Use the following flowchart to understand how your system interacts with these entities when an account holder links an account.

1. The account holder requests to link their accounts.
2. You call the Get External Account Link Access endpoint to start the access token creation process.
3. Galileo generates and returns an access token.
4. You load the SDK required to communicate with your link provider, such as Mastercard Data Connect, which sends a request to create a customer ID and connect URL.
5. The link provider returns the customer ID and connect URL.
6. You provide the interface for the account holder to specify their external account information.
7. The account holder uses your interface to select their external bank or financial institution and input their credentials.
8. The external bank authenticates the user.
9. The link provider sends your system webhooks reflecting authentication.
10. You call the Load External Account Links endpoint.
11. Galileo initiates the account link.
12. Galileo sends your system an HTTP response reflecting a pending status.
13. Galileo requests account owner and ACH details from the link provider.
14. The link provider returns the account owner and ACH details.
15. Galileo performs internal verification to confirm the user's identity.
16. Galileo sends the EAST: external_account_status_change message with the status (ACTIVE or FAILED).
17. The account holder sees a confirmation of a successful link or failure.

Events API

During the external account link process, Galileo sends the EAST: external_account_status_change event any time the status of the external account link changes. This event is first triggered when Galileo generates a token and sends it to you in the endpoint response. Subsequent status changes also trigger this event message.

The possible values for this status are:

• PENDING — The link to the external account is being established.
• ACTIVE — The link to the external account has been successfully set up.
• FAILED — The link to the external account process failed.
• DELETED — The link to the external account has been removed.

When status: failed, the status_reason field is populated with one of the following messages: