I am an American and I have Motorola razor with Q-Tel sim card whenever I go to USA my phone does not work. You can only receive calls but you cannot call from your cell phone. You can buy sim from T –mobile but calls are expensive when you use this service. Now days they are selling disposable cell phone in USA which you can buy for $20 once you ran out of your allotted minutes you can call toll free number and buy additional minutes with your credit cards AND ITS CHEAP.