B2B E-Invoicing in Belgium: Update on the 2026 Mandate and Tax Reform 

B2G Invoicing: Already Mandatory as Part of Belgium’s Reform

Since March 1, 2024, B2G electronic invoicing (Business-to-Government) has been mandatory in Belgium, using the Peppol network and format. Other invoicing practices, such as B2C or international transactions, are not yet regulated and require the recipient’s consent. This Belgium reform is part of a broader push to harmonize invoicing systems.

B2B Invoicing and Tax Reform

The B2B mandate requires both the issuance and reception of electronic invoices for all businesses, in line with the European directive. Invoices must be produced, sent, and received in a structured format that allows for automated electronic processing. Compliance with the EN 16931 standard is mandatory under this new Belgian tax reform.

In Belgium, electronic invoices must also adhere to the required semantic standards, format, and communication methods outlined by law. The Peppol framework, with its Peppol BIS format and Peppol e-delivery network, is the default.

Alternatives and Peppol Interoperability

While it is possible to use another syntax, provided there is an agreement and it is compatible with the semantic standard, the Peppol 4-corner interoperability model is emphasized. The 5-corner model, involving the tax authority, will be introduced alongside e-reporting as part of the ViDA directive. This update is a key aspect of the Belgian tax reform.

Hermes Platform and SEPA B2B Mandate

The Belgian tax authority will continue to offer the Hermes platform as a minimum service for businesses that do not yet have a service provider. This temporary measure aligns with European Commission recommendations, which favor non-centralized 3-corner architectures. Additionally, discussions are underway to ensure operators provide low-cost services for small businesses, particularly regarding the SEPA B2B direct debit.

Cost Savings from the Reform

The Belgian government has published a study on the benefits of electronic invoicing. Automating the invoicing process leads to cost savings of 64% compared to a PDF invoice (9.68 € per invoice) and 75% compared to a paper invoice (12.48 € per invoice). These significant savings are part of the expected outcomes of the Belgian tax reform.

Financial Support for the Transition

To ease the adoption of electronic invoicing under the B2B mandate, the Belgian government offers financial support. This includes tax deductions of up to 120% of the costs incurred for consulting services or the purchase of e-invoicing solutions. This measure is part of the government’s commitment to supporting businesses as they transition under the new Belgian tax reform.