Can one use a cell phone from a different company then the one that services you?
The only way to use verizon or any other carrier phone for at&t or vice versa is to buy unlocked phone I think. For certain GSM phones, you MUST check specifically with your carrier to ensure a particular model will accept the mHz bands in your area, regardless what the coverage map says. GSM phones that are sold as “unlocked” are guaranteed to function for cellular and text messaging use on GSM providers in the United States. Internet and extra feature functions are not guaranteed on unlocked GSM cell phones. You can find cheap ones online, check out resource below. Just ask questions before you buy anything and call your carrier to make sure.