A system and method for providing call mobility for a dual-mode phone between a cellular network and a home wireless network for a dual-mode phone having a cellular identity and a home identity, wherein the home identity is active when the dual-mode phone is in communication with the home wireless network. The system comprises a residential gateway to connect the home wireless network to a public network, and a VoIP service provider in communication with a mobile switching center on the cellular network and the public network. After placing or receiving a call, the dual-mode phone sends a signal to the residential gateway to initiate the movement of the call between the cellular network and the home wireless network while the call is ongoing.