An accounting framework is provided for a communications system having a plurality of service providers, including cellular service providers and/or data network service providers, e.g., Internet service providers. Accounting units containing accounting information are exchanged between service providers to allow the service providers to charge for usage of services. The accounting units have a predetermined format to allow them to be exchanged between different service providers. Each accounting unit includes a plurality of fields, including a service type field, a usage of radio interface field, a usage of a visited or external network field, a usage of mobility management field, a quality of service field, a usage of a packet data protocol field, and other fields. Users may be charged for services based on these fields.