Will a Verizon iPhone work on a t-mobile SIM card?

My friend is giving me his iPhone 4 from Verizon. My dad says I can just put in the SIM card and it will work. Will it work or do I need to unlock it or something

Consider trying it before you ask for help.

Nope. They are two different technologies. You could put it on att, but not verizon

No. 1st off Verizon is a CDMA network. They don't use SIM cards. 2ndly the iPhone 4 for Verizon is a CDMA phone only. No SIM slot.

A Verizon iPhone 4 will not accept a SIM card.