There may come a time when you will need to add an existing phone to your AT&T account. This may occur in the event that you want to swap out a phone or add another line to your services. Whatever the reason may be, adding an existing phone to your AT&T plan is easy to accomplish. If you are adding an existing phone line to your account, inform the representative that you would like to upgrade your account to add an additional line of service. If you have an individual plan, you will need to upgrade to a shared plan. Provide the representative with the ESN or HEX number of the AT&T phone that you would like to add to the account. Warnings Writer Bio
