Can you change your cell phone to another carrier and keep your cell phone?

Not usually, it depends on the carrier. The carriers use different technologies. Some of them use CDMA, like Verizon and Sprint. HOWEVER, only Verizon phones will work on Verizon because they lock them to do so. Carriers like At&T use the GSM network. These are the types of phones that have sim cards in them. Those phones are more interchangable. Yes, you can but you have to get a unlocked version of that phone and you can only use it for companys that use the same satelites as the company that your getting the original phone from