Belgium B2G
E-Invoicing (Mercurius): Electronic Invoicing for the Public Sector
Belgium’s B2G e-invoicing framework requires suppliers to issue structured electronic invoices to public administrations via the Mercurius platform.
Connecting your ERP to the Mercurius platform
key implementation dates
Stay updated on implementation timelines and e-invoicing obligations in Belgium
Since 2017, Belgian public administrations must receive structured electronic invoices, as mandated by the EU e-Invoicing Directive
Since November 2018, electronic invoicing has been mandatory for central government suppliers in Belgium.
Since March 2020, the obligation has been extended to all suppliers invoicing Belgian public sector entities, making structured B2G e-invoicing fully mandatory nationwide.
Belgium B2G E-Invoicing Overview
Implementation
Mandatory for all suppliers invoicing Belgian public administrations since March 2020, following a phased rollout aligned with EU requirements
Tax Authority
Belgian Federal Public Service Policy and Support (BOSA), in coordination with public sector entities
Format
Structured electronic invoices compliant with the European standard EN 16931, typically exchanged via the Peppol network
Digital Signature
Not required under the current mandate, provided authenticity and integrity are ensured through compliant systems and Peppol-based transmission
Archiving
Electronic invoices must be archived for a minimum of 7 years, in accordance with Belgian VAT and accounting regulations
Other Belgian regulations
Are your invoices being accepted without errors by Belgian public authorities?
Frequently asked questions
What is Mercurius and how does it work in Belgian B2G e-invoicing?
Mercurius is Belgium’s federal e-invoicing service that enables public administrations to receive structured electronic invoices. It acts as a central access point for B2G e-invoicing and relies on the Peppol network to ensure secure, standardised, and interoperable invoice exchange between suppliers and public sector entities.
Which public administrations in Belgium require electronic invoices?
All Belgian public sector entities are required to receive electronic invoices, including federal, regional, and local administrations, as well as public bodies and agencies. The obligation applies uniformly across the public sector, meaning suppliers must issue structured electronic invoices regardless of the specific administration they are invoicing.
Is Peppol mandatory to invoice Belgian public sector entities?
While the legal requirement focuses on compliance with the European e-invoicing standard (EN 16931), Peppol is the recommended and most widely used network for B2G e-invoicing in Belgium. In practice, Mercurius is fully aligned with Peppol, making it the standard approach for exchanging compliant electronic invoices with public administrations.
Can companies send B2G invoices directly from their ERP systems?
Yes. Companies can send B2G electronic invoices directly from their ERP systems by integrating them with the Peppol network and the Mercurius service. Through proper system integration, invoices can be generated, validated, and transmitted automatically from the ERP, eliminating manual uploads and reducing the risk of errors. This approach is especially effective for organisations using SAP or other enterprise ERP platforms.
Can Mercurius be integrated with SAP or other ERP platforms?
Yes. Mercurius can be fully integrated with SAP and other ERP systems through Peppol-enabled solutions. With the right integration architecture, businesses can automate end-to-end B2G invoicing processes directly from their ERP, including invoice creation, format compliance, transmission, and status handling. Experienced eCompliance and integration partners such as Code10 can ensure seamless connectivity while aligning with Belgian and EU requirements.
Our Approach to SAP Integration and B2B E-Invoicing Compliance
Complying with Belgium’s B2G e-invoicing requirements means ensuring that invoices sent to public administrarion are issued in the European standard format and transmitted via the Peppol network to the Mercurius platform. This requires not only structures data generation, but also secure and validated integration between your ERP and Belgian public sector infrastructure.
At Code10, we combine SAP standard implementation with specialized expertise through our eCompliance Hub to enable fully automated, compliant invoice exchange. Where standard SAP functionality needs reinforcement, we develop targeted integration enhancements to ensure reliable delivery, format validation and seamless interoperability with Mercurius and certified Peppol Access Points.
