A method for personalising a smart meter or smart meter gateway security module by means of a first computer system, wherein energy consumption-specific measurement data elements are detectable by means of the smart meter (142; 144; 146; 148), wherein the security module has cryptographic functions for carrying out a cryptographically encrypted communication of the measurement data elements received by the smart meter (142; 144; 146; 148) or the smart meter gateway and a second computer system of a utility company and/or meter operators, wherein the security module is assigned a unique identifier, wherein the method comprises the following steps: - providing the security module, - storing the identifier in the security module, - generating an asymmetric cryptographic key pair by means of the first computer system and storing the key pair in the security module, - signing the public key of the key pair and the identifier to obtain a certificate and storing the certificate in the security module, wherein the signing is carried out by the first computer system, wherein the security module is designed such that, once the key pair has been stored, an initial communication access to the smart meter (142; 144; 146; 148) and/or the smart meter gateway is possible exclusively for the first computer system, wherein the security module can be released for communication with the second computer system by the initial communication access by the first computer system, - installing the security module in the smart meter (142; 144; 146; 148) or the smart meter gateway, wherein, on account of said installation, there is an irreversible binding process between the security module and the smart meter (142; 144; 146; 148) or the smart meter gateway, wherein, on account of the connection of the security module to the smart meter (142; 144; 146; 148) or the smart meter gateway, a linking process on the smart meter (142; 144; 146; 148) or the smart meter gateway is started, wherein, by means of the linking process, an inseparable logical link is produced between the security module and the smart meter (142; 144; 146; 148) or the smart meter gateway, wherein the inseparable logical link comprises an irreversible copying process of the certificate and/or the unique identifier of the security module to a memory region of the smart meter (142; 144; 146; 148) or the smart meter gateway. - providing the security module, - storing the identifier in the security module, - generating an asymmetric cryptographic key pair by means of the first computer system and storing the key pair in the security module, - signing the public key of the key pair and the identifier to obtain a certificate and storing the certificate in the security module, wherein the signing is carried out by the first computer system, wherein the security module is designed such that, once the key pair has been stored, an initial communication access to the smart meter (142; 144; 146; 148) and/or the smart meter gateway is possible exclusively for the first computer system, wherein the security module can be released for communication with the second computer system by the initial communication access by the first computer system, - installing the security module in the smart meter (142; 144; 146; 148) or the smart meter gateway, wherein, on account of said installation, there is an irreversible binding process between the security module and the smart meter (142; 144; 146; 148) or the smart meter gateway, wherein, on account of the connection of the security module to the smart meter (142; 144; 146; 148) or the smart meter gateway, a linking process on the smart meter (142; 144; 146; 148) or the smart meter gateway is started, wherein, by means of the linking process, an inseparable logical link is produced between the security module and the smart meter (142; 144; 146; 148) or the smart meter gateway, wherein the inseparable logical link comprises an irreversible copying process of the certificate and/or the unique identifier of the security module to a memory region of the smart meter (142; 144; 146; 148) or the smart meter gateway.