DLMS UA and STS Association Forge Landmark Liaison Agreement to Unify Smart Prepayment Standards

Summary: DLMS UA and STS Association sign a landmark liaison agreement in January 2026 to unify smart prepayment standards, enabling seamless integration of DLMS/COSEM data model with STS credit token technology.

The DLMS User Association (DLMS UA) and the STS Association signed a landmark Liaison Agreement on January 8, 2026, marking a pivotal step forward in the evolution of interoperable, secure, and future-ready smart prepayment metering systems worldwide. The collaboration brings together two of the most widely adopted global standards in the metering industry—the DLMS/COSEM Data Model and STS Credit Token technologies—promising stronger interoperability and enhanced value across the entire metering ecosystem.

Under the agreement, the two organizations will jointly promote aligned visions and solutions, with a particular focus on prepayment. The partnership ensures that STS credit tokens can be seamlessly transported using the DLMS/COSEM data model, with both sides committing to develop the necessary specifications, mappings, and enhancements to support this integration within DLMS Generic Companion Profiles.

"This collaboration marks an important step forward in aligning two widely adopted global standards," the DLMS UA stated in its official announcement. "By working with the STS Association, we will strengthen our prepayment offering, expand our reach into multi-utility applications, and ensure that DLMS-based systems remain at the forefront of secure, flexible, and future-ready smart metering solutions," said Sergio Lazzarotto, DLMS UA President.

The liaison agreement also covers roadmap synchronization, ensuring that future developments in data exchange and token technologies evolve in a coordinated manner. Both organizations will collaborate on market education and documentation to highlight the benefits of combining the DLMS data model with STS token standards, with plans to expand use cases beyond electricity to include water, gas, and heat metering.

STS (Standard Transfer Specification) defines a secure messaging system for carrying information between a point-of-sale and a meter and is widely used in electricity metering and payment systems. It is recognized internationally through IEC 62055-41, -51, and -52 standards, and the STS Association manages a formal product certification program.

DLMS/COSEM (Device Language Message Specification / Companion Specification for Energy Metering) is the global standard for data exchange in energy metering and control, defined by IEC 62056 series standards. The DLMS Green Book Edition 12, the latest version of the architecture and protocols specification, reflects ongoing evolution of the standard.

Key Standards Comparison

Industry analysts view the liaison agreement as a significant development that addresses a long-standing challenge in the smart metering market—the lack of seamless integration between prepayment token systems and advanced metering infrastructure data models. For utilities operating or planning hybrid prepaid-postpaid metering environments, the alignment of these two standards is expected to reduce integration complexity, lower deployment costs, and improve the customer experience.

The agreement comes at a time when the International Electrotechnical Commission (IEC) is also advancing work on dual-mode interoperability in its IEC 62056-53 standard revision draft, which specifies requirements for DLMS/COSEM protocol stacks to support both PLC and wireless protocols on a single physical interface with a unified application layer interface.

The DLMS UA and STS Association plan to release joint technical specifications and conduct educational webinars throughout 2026 to support meter manufacturers, system integrators, and utility providers in implementing dual-standard solutions.

Source: DLMS UA Official Announcement (January 8, 2026), STS Association, IEC Standards, industry analysis
Published: August 30, 2026