Already own a Globalstar phone and need month-to-month service? Our four month prepaid airtime plan allows you to activate your existing telephone number and prepay for usage up to six months. You will also receive UNLIMITED voice usage in the US, Canada and the Caribbean free of charge. Roaming Outside of these areas is $2.00/min and credit card will be required in case any roaming or international calls. Provide us with the mobile # and ESN # of your device and we will activate the phone within 24-48 hours.