I could be wrong and my wife will tell you that I usually am but I thought when these are used via prepaid they are basically the same as a phone sim. I normally use my actual phone and just tether it so I dont know how useful this will be to me long term but I just add the $3 a day plan on my phone and then cancel it after a day. Not sure if this stick works the same way but would think it would and as far as the credit goes....it is 90 days unless you are gold and then it is a year.