Centralized charging systems and methods are disclosed for providing offline charging and online charging for a plurality of network elements. The centralized charging system is implemented in a communication network between the network elements and offline/online charging systems. A network element interface of the centralized charging system receives charging request messages from CTFs in the network elements. An accounting data forwarding function processes charging data in the charging request messages to determine if offline or online charging is invoked for the services. For offline charging, the accounting data forwarding function generates offline accounting request messages that include the charging data. For online charging, the accounting data forwarding function generates online accounting request messages that include the charging data. The charging system interface then transmits the offline accounting request messages to the offline charging system, and transmits the online accounting request messages to the online charging system.