Q: When using FaceTime on an iPhone 5 is this part of your unlimited Internet data? I know that some numbers aren’t part of your minutes package.
A: The short answer is that FaceTime uses your iPhone’s Internet connection and has absolutely nothing at all to do with whatever voice minutes plan you are on with your carrier.
FaceTime calls travel over the Internet in much the same way as e-mail, instant messages, web browsing, or other forms of data. If you’re on a Wi-Fi network, that connection will be used for FaceTime and will not apply against your cellular data plan at all. If you are not on a Wi-Fi network, FaceTime calls will travel over the cellular data network and will count against whatever data plan you have available—unlimited or otherwise.
As mentioned above, FaceTime traffic is treated as any other form of data, although video calls use more bandwidth than traditional e-mail or web surfing; expect about 3-5MB of data usage for every minute of FaceTime video calling.
The number that you are calling with FaceTime has no bearing on this at all. Phone numbers are treated by FaceTime simply as addresses on the FaceTime network, and Apple simply allows you to use your cellular phone number as a FaceTime address for convenience—the number is not otherwise related to your actual cellular account in any way beyond an initial verification process that occurs in the background simply to authenticate it as a valid number.
The only time you will incur any charge against your minutes in relation to FaceTime is if you begin with a traditional cellular telephone call and then switch to FaceTime. In this case, the initial call travels over the cellular network in the same way as any other voice call. Once you switch to FaceTime, however, the cellular call is actually disconnected in favour of the entirely Internet-based FaceTime call. The voice portion of the call will be charged against your minutes, and the FaceTime portion against your cellular data plan (if you’re not using Wi-Fi).