Receive unlimited calls and text messages on your Metro phone from Mexico while you are within the United States.
Make unlimited calls and text messages while you are within Mexico to phones in the United States and Mexico.
Send unlimited messages from your Metro phone to select countries while you are in either the United States or Mexico.
This add-on also enables data roaming in Mexico. You can use however much data was in your base plan as roaming data.
Metro says, "You must reside in the USA and primary usage must occur on our US network."