To provide a gateway device that achieves charging control in accordance with a RAT being used by a UE even when the UE is performing communication using different RATs at the same time, the present gateway device (30) includes a management unit (31) configured to, when a communication terminal (10) forms communication aggregation by performing a first radio communication using a first radio access technology and a second radio communication using a second radio access technology, manage at least one bearer assigned to the communication terminal (10) in association with information indicating the first and second radio access technologies, and a charging system communication unit (32) configured to transmit the information indicating the first and second radio access technologies to at least one policy charging control device (40) that performs charging control.