Find out how a Primary Account is different from a Sub Account.
A Primary AT&T Account is associated with the account owner (person to whom the bill is sent). This account has an associated User ID, which you will need to reset or change your password. Your User ID is found on the Internet Service section of your bill:
Note: You can also View Your Bill online from the Account Center.
A Sub Account is associated with accounts set up under a Primary Account. For example, the Business Owner may have the "Primary Account" and the employees will have "Sub Accounts." Each account will have its own User ID and password(s). The User ID for a Sub Account is not on the bill.