Nowadays, in mobile communication only the Mobile Network Operator (MNO) of the callee is able to terminate his calls. Thus, in the MNOs call-termination market there is only one player profiting from call-termination rates; in turn this market is considered to be a de facto monopoly since the early days of the introduction of commercial mobile communication services. Given this monopoly fact, the only solution against a potential speculation by MNOs was the regulation of termination rates. However, since the initiation of mobile communications, many issues on mobile terminal devices and network infrastructure have changed. Furthermore, today the mobile networks infrastructure does not support only voice services but data as well. In such an environment multiple MNOs could terminate a call. However, in this case the caller has to set only his final cost preference without any knowledge on MNOs termination rate charging policies. Therefore, this paper considers those changes and challenges the monopoly of the MNOs call-termination by proposing an Auction-based Charging and User-centric System called “AbaCUS”, which overcomes the monopoly obstacle of this market. The key characteristic of the auction proposed for AbaCUS is the honest bid that participants are “forced” to make. Finally, this work is expected to show that MNOs will benefit by the existence of a calltermination-free market through the establishment of Quality-of-Service (QoS)-guaranteed services.