Controller and method for Handover (HO) based 1×CSFB communicates Calling Party Number (CPN) to User Equipment (UE) a in a cellular communication system. A first solution provides Interworking Solution (IWS) adding CPN sent to target Base Station Controller (BSC) via Mobile Switching Center (MSC) in Interoperability Specification (IOS) HO messages. A second solution provides that IWS sends CPN with Air Interface HO message and stores the CPN until UE transition to the target Radio Access Network and acquires a traffic channel. A third solution provides that IWS receives CPN from MSC with a paging message and stores the CPN until UE transition to the target Radio Access Network and acquires a traffic channel. A fourth solution provides sending AWI message to the target Radio Access Network from the MSC. A fifth solution provides that IWS sends CPN via Feature Notification Message (FNM) data tunneled to UE before the paging message to let user decide whether to accept a call before leaving 3G/4G cellular communication.