Abstract: A system and a process for processing payments and transactions between payers (13) and payees (27, 29, 14, 14a, 13a, 46) associated to the system, using a first server (20) interconnected with telecommunication means (18, 19, 28, 47) with first data storage means (22) containing information on each associated payer (13) consisting of at least an admissible telephone number, at least a authorization criterion for authorizing a transaction, and a safety criterion associated to the admissible telephone number, as well as an admissible identification code of each payee; second data storage means (21) that contain a second information referring to the type of digital mobile telephone (16, 41) belonging to each telephone number; selecting means (20h) for verifying one of the telecommunication equipments (18, 19) that communicates with the digital mobile telephone (16, 41) identified by the admissible telephone number by means of a telecommunication service being compatible with the type of digital mobile tele