According to the plan information, all the prepaid plans cover calls/text to the USA ....
"UNLIMTED STND CALLS & TEXT TO SELECTED DESTINATIONS: Brazil, Canada, Chile, China, Colombia, France, Germany, Hong Kong, Indonesia, Ireland, Japan, Malaysia, New Zealand., Singapore, South Korea, Taiwan, Thailand, United Kingdom, USA, Vietnam"
As for roaming, there is not any unlimited call/text add-ons. You have to add roaming add-on funds to the existing account (extra), and then in the US it will consume those funds at the below call rates. Data will be charged at $3 per MB. Probably best to get a local sim card if overseas.
Countries Rate per min Rate per text sent Rate per text received
United States (USA)
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