The purpose of the present invention is to provide a communication terminal which ensures that timings of paging coincide with each other between a UE and a control device when an extended idle mode DRX (eDRX) parameter is updated in the control device. A communication terminal (10) according to the present disclosure is provided with: a receiving unit (11) which receives an in-zone registration acceptance message or a location registration acceptance message transmitted from a control device (30); and a transmitting unit (12) which transmits an in-zone registration completion message or a location registration completion message to the control device (30) when the in-zone registration acceptance message or the location registration acceptance message includes a first eDRX parameter.