Update of technical documentation in Belgium related to GKS 2.0 solutions: API protocol between FDM and FIN-Cloud

Belgium’s FPS Finance has released version 1.08 of the Registered Cash Register System (RCRS) Technical Specifications, refining the API protocol between the Fiscal Data Module (FDM) and FinCloud. The update introduces new data elements, security adjustments, and guidance on message size limits, enhancing accuracy, reliability, and compliance in electronic fiscal data reporting for the HoReCa sector.

The Technical Document on Registered Cash Register System (RCRS) – Technical Specifications concerning requirements for communication between FDM and FIN-Cloud has been updated with version 1.08, published on the FPS Finance website.

This new version marks additional development of the API protocol between the Fiscal Data Module (FDM) and FinCloud (FPS Finance). The document serves as a guide for manufacturers that want to develop FDM solutions for the Belgian market. Over the past year, the specification has gone through multiple refinements, starting with the initial version in May 2024.

The most recent v1.08 update introduced changes based on live testing feedback. Notably, three new data elements – vatNo, estNo, and protocolVersion – have been added, affecting multiple sections of the mentioned specification. These changes ensure that financial data exchange is more accurate and precise with other regulations. Another added improvement is the inclusion of an important note on message size limitations in section 12.1, which will help manufacturers avoid technical issues in real-world implementations. Additionally, sections 12.3.2 and 12.5.5.7 received adjustments regarding the handling of the shared secret, further reinforcing system security. All transactions processed through registered cash register systems in the HoReCa sector that fall under fiscalization must be transmitted electronically to FPS Finance.

By improving the protocol, authorities gain a more reliable communication process between FDM and FPS Finance, which will influence horizontal monitoring and targeted tax audits. Each revision of the protocol has responded to technical and operational feedback, with v1.08 representing the most detailed set of improvements in this regard.