Pricing method for utility consumptions within a smart grid comprising a plurality of utility meters (U1-U8) each associated and connected to a plurality of utility management centers (P1-P3) through a plurality of intermediate data concentrators (C1-C4) each identified by a data concentrator identifier DCid, each utility meter being identified by a utility meter identifier Uid and being adapted to produce and send secured utility meter messages DTup u,c to one of said data concentrators, each data concentrator being adapted to produce and send secured reports to said management centers (P1-P3), each identified by a management center identifier Pid, said method comprising the steps of: - receiving, by said data concentrator (C1-C4), a secured data concentrator message comprising at least a tariff table from each of said utility management centers (P1-P3), said tariff table comprising at least one time interval [DT1, DT2] per a period of twenty-four hours, and a rate associated to said time interval [DT1, DT2], - decrypting and/or verifying the authenticity and the integrity of said data concentrator message; in case of failure or unsuccessful result: interrupting the processing of said data concentrator message, - selecting, by said data concentrator (C1-C4), the lowest rate for each time interval [DT1, DT2] among the rates of all time intervals of all tariff tables, in order to derive an advantageous tariff table, - receiving, by said data concentrator (C1-C4), said utility meter messages DTup u,c from said utility meter (U1-U8), each of these utility meter messages DTup u,c comprising: a metering data measurement DTup reported by the utility meter which sent this message DTup u,c, its utility meter identifier Uid, said data concentrator identifier DCid and said management center identifier Pid, - decrypting and/or verifying the authenticity and the integrity of said utility meter messages, in case of failure or unsuccessful result: interrupting the processing of said utility meter message, - determining, on the basis of several metering data measurements DTup, a metering counter differential consumption value ΔCPT calculated by difference of two metering counter consumption indexes CPT measured by said utility meter within a time period interval ΔT defined by a first time T1 and by a second time T2, - assigning to said metering counter differential consumption value ΔCPT the utility management center (P1-P3) suggesting the lowest rate for the time period interval ΔT comprised between said first time T1 and said second time T2, - establishing, for each management center (P1-P3), a report containing at least the metering counter differential consumption value ΔCPT assigned to this management center (P1-P3) together with the utility meter identifier Uid to which this value ΔCPT refers, - encrypting and - securing said report before sending it from said data concentrator (C1-C4) to this utility management center (P1-P3) which will process said report only after having decrypted it and/or checked its authenticity and its integrity. - receiving, by said data concentrator (C1-C4), a secured data concentrator message comprising at least a tariff table from each of said utility management centers (P1-P3), said tariff table comprising at least one time interval [DT1, DT2] per a period of twenty-four hours, and a rate associated to said time interval [DT1, DT2], - decrypting and/or verifying the authenticity and the integrity of said data concentrator message; in case of failure or unsuccessful result: interrupting the processing of said data concentrator message, - selecting, by said data concentrator (C1-C4), the lowest rate for each time interval [DT1, DT2] among the rates of all time intervals of all tariff tables, in order to derive an advantageous tariff table, - receiving, by said data concentrator (C1-C4), said utility meter messages DTup u,c from said utility meter (U1-U8), each of these utility meter messages DTup u,c comprising: a metering data measurement DTup reported by the utility meter which sent this message DTup u,c, its utility meter identifier Uid, said data concentrator identifier DCid and said management center identifier Pid, - decrypting and/or verifying the authenticity and the integrity of said utility meter messages, in case of failure or unsuccessful result: interrupting the processing of said utility meter message, - determining, on the basis of several metering data measurements DTup, a metering counter differential consumption value ΔCPT calculated by difference of two metering counter consumption indexes CPT measured by said utility meter within a time period interval ΔT defined by a first time T1 and by a second time T2, - assigning to said metering counter differential consumption value ΔCPT the utility management center (P1-P3) suggesting the lowest rate for the time period interval ΔT comprised between said first time T1 and said second time T2, - establishing, for each management center (P1-P3), a report containing at least the metering counter differential consumption value ΔCPT assigned to this management center (P1-P3) together with the utility meter identifier Uid to which this value ΔCPT refers, - encrypting and - securing said report before sending it from said data concentrator (C1-C4) to this utility management center (P1-P3) which will process said report only after having decrypted it and/or checked its authenticity and its integrity.