The prices used for the charging of data and multimedia services in communication networks depend on the profit maximization goals of the network operators and service providers, and the market forces affecting the industry. In many scenarios the tariff rates used increase with the speed of the access channel. Next generation networks will offer higher data rates. Users will not get incentives to utilise the extra capacity if current tariff structures are retained. In this paper, a novel, network congestion dependent dynamic billing scheme is proposed. Differentially priced network service profiles are introduced, and the use of DiffServ and connection admission control for QoS provisioning is explored. A hybrid billing scheme is designed. The implementation architecture is given, and a testbed for evaluating the scheme is built.