The STS Association, as the custodian of the STS prepayment metering technology standard was founded in 1997. The STS Association was formed to take over the STS technology, maintain the necessary infrastructure, promote the technology internationally, and further develop the standard to meet emerging international demands for additional functionality.

The key operational objectives of the association are to maintain the necessary infrastructure; promote the technology internationally and further develop the standard to meet emerging international demands for additional functionality. The Association ensures interoperability between system components from different manufacturers of prepayment meter and vending systems by accrediting and maintaining a list of test laboratories that ensure compliance to STS standards. It also manages the availability of encrypted vending keys to manufacturing members via its key management centres and ensures consistent use of manufacturer codes as well as meter serial numbers.

The Standard Transfer Specification is the global standard for the transfer of electricity and other utility prepayment tokens, ensuring inter-operability between system components from different manufacturers by accrediting test laboratories, issuing compliance certificates and publishing a register of STS compliant products.

The STS strives to continuously meet emerging international demands for additional functionality of prepayment systems. The latest edition of the specifications, STS Edition 2 falls in line with the Association’s major focus on innovation, introducing brand new features compatible with modern metering technologies, maintaining backward compatibility to the current systems in use, and more importantly, it enables the use of the latest state of the art cryptographic algorithms, while also introducing many new features to keep abreast with modern smart metering technologies. The specification suite allows STS-compliant equipment from any number of suppliers to be integrated into an Electricity, Water or Gas sales system.