The networks (GSM or CDMA) that the phone is able to work with are usually found in the detailed product description. You can see find the detailed product description by scrolling down the product page. If it is not specified in the product description which network the phone works with, then the phone can work with both CDMA & GSM networks. GSM networks are networks like T-Mobile, A T & T, and Cricket while CDMA networks are networks like Verizon, Sprint, and Boost Mobile.