Hi all.. sorry to contradict.. but you can definatly activate global roaming with prepaid mobiles. BUT only in some countries. I know my mum had her prepaid working fine all over Europe, but as soon as she got to New Zealand it stopped working. I called optus for her and they said they only have a limited number of 'global roaming' countries for prepaid and NZ was not one of them.

So.. not sure if Thailand is or not.
That is just optus though.. you would have to call your provider to find out if they have global roaming for prepaid or not.

Grace

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