Abstract: A method for providing a service transaction for a mobile device of a user at a point of sale (POS) of a supplier, wherein the method comprises the steps of sending (S2) by said mobile device an individual supplier code (SC) read (S1) by said mobile device from a supplier tag located at the point of sale (POS) of said supplier to a server of a service provider; returning (S5) a service valid message (SVM) by said server of said service provider to the mobile device if the supplier code (SC) belongs to a registered supplier of the respective service; and performing (S6) a service transaction of the respective service at the point of sale (POS) of the registered supplier in response to the service valid message (SVM) received by the mobile device.