A method for performing charging in a telecommunications system, comprising: storing at a subscriber information store subscription information including charging arrangement information indicative of the charging arrangement for a first communication terminal operating in the telecommunications system; providing by means of packet data interface apparatus packet data communication services to the first terminal, the packet data interface apparatus being capable of interfacing between the first communication terminal and a packet-switched data link to another communications terminal; generating by means of the packet data interface apparatus charging messages indicative of the usage of the packet data communication services by the first terminal; transferring the charging messages to charging apparatus; and performing by means of the charging apparatus a charging operation to attribute to a subscriber for the first communications terminal a charge for use of the communication services by the first terminal; the method further including the steps of: transferring the charging arrangement information to the packet data interface apparatus; and storing at the packet data interface apparatus the charging arrangement information for the first communication terminal; and wherein the step of generating charging messages comprises generating the said charging messages dependant on the charging arrangement information for the first communication terminal.