In order to access a Google Merchant Center account, you must be added as a user by a Merchant Center admin first. A single Merchant Center account can have multiple users and users can connect their individual Google account with multiple Merchant Center accounts as needed.
Admins will need to determine what level of access each new user is granted, these roles can vary depending on the services enabled in a Merchant Center account.
Adding a user is simple and each user that is invited must log in with their own Google account login information. This prevents the need to give out your login information.
To grant access to additional users, follow these steps:
Sign in to your Merchant Center account.
Click the tools ⚙️ icon, then select Account access under the “Settings” menu.
Click the plus button ➕.
Enter the email address of the person you want to invite.
Click Add user.
On the next page, select the level of user access you'd like to grant, and email preferences for that user.