Contact AT&T customer service to request a second landline. Tell the representative that your service information, such as name and address. You may be asked to provide the last four digits of your Social Security number.
Set up a day and a time frame when you plan to be home for the technician to arrive. Because a second line needs to be connected off AT&T's main phone cables, the technician needs to come and install all of the necessary phone jacks and cables.
Connect your phones to the new landline jacks. Begin using your new phone number.