I'm going to Switzerland, Germany, Italy, and Austria for a 3 week trip. I'm going to buy a prepaid sim card with the usual stuff (some data, some texts, and some inexpensive calls per minute to the u.s...i've had problems with skype).
There's 1 day around the middle of my trip where I will have around a 25 minute phone call with my employer. I'm with AT&T and for that day I'm going to get the $10 passport so that it's easy on my employer and I (thank you to someone on this forum who suggested that!).
I know to put back in the prepaid SIM for Europe after I've had the call using my AT&T sim, but do I have to reregister the European sim and pay again? I know this is a stupid question to ask!