Hey there Peter1945. We want to ensure you are able to use all the features on your phone without the worry of incurring charges. I am happy to inform there are is no cost to enable the HD feature on your phone. However, when using HD Video or HD calling, you are billed minutes of use for HD voice calling. Video calling, is billed minutes of use plus data usage. When installing the HD feature on your phone you are prompted regarding data usage.
Also, please keep in mind when using HD calling while on Wi-Fi you are not billed minutes of use or data usage.
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