After having to get a new sim card to switch my bionic to a different line on my plan. i was told by verizon tech support that the card is permantly tied to the phone and to the particular line on an account. (You can change the ph# on that line and keep the same card) Any other change requires new sim. This is the info i got from vrz tech so take it for what its worth. He seemed like he knew what he was talking about. Lol