T-Mobile retired its 2G GSM network on Monday, August 3, which means all three major carriers in the United States have now ended 2G service. T-Mobile kept its 2G network active because it still had some legacy customers who were using it. Some customers visiting the United States and using international roaming carrier agreements for connectivity also needed 2G for voice calling, but T-Mobile worked with carriers globally to prepare for the end of its 2G network.