I found this information: And this: Both make it very clear (to me) that the ICCID is nothing more than a way for your carrier to identify you and know whether or not you are allowed to attempt to use their network. It is nothing more than an identification number on your SIM, not a separate card for your phone. As far as interchangeability goes, I imagine each phone needs to be activated to each card, so you can't swap without the card being activated to that phone. EDIT: Just to be clear, I was only trying to help save you from purchasing a phone you couldn't use on your carrier. I would be very pleased to hear that you can use the Pro 1 without any issues. It has just been my experience that Sprint and Verizon don't play nice with "unknown" phones. Hopefully the Pro 1 having CDMA bands will help with this? I sincerely hope it works out for you.