E-invoicing in Belgium: End of the grace period and full enforcement of the mandate now in effect

On 27 March 2026, the Belgian FPS Finance announced in on the Belgian radio station ‘Radio 2’ that the three-month grace period for the Belgian B2B e-invoicing mandate will not be extended. As of 1 April 2026, businesses can no longer rely on the grace period and must ensure full compliance. A specific exception remains for self-billing invoices, where an additional implementation window has been granted to allow businesses and Access Points to finalize the necessary technical integrations.

For more information about Belgian e-invoicing, we kindly refer to our previous newsflashes (Grace period but no general postponement of the Belgian e-invoicing mandate, Mandatory B2B e-invoicing published in the Belgian Official Journal - entry into force 1 January 2026).

The end of the grace period

What the grace period covered

From 1 January until and including 31 March 2026, businesses able to demonstrate that timely and reasonable efforts had been made to comply with the Belgian e-invoicing mandate - but who still faced technical challenges - have benefited from a three-month tolerance period.

This window has provided these businesses the opportunity to regularize their situation without being sanctioned during the first three months of 2026.

Note on Self-Billing Transactions: While the general grace period for standard B2B invoices concludes on 31 March 2026, the administration acknowledges the ongoing technical complexities in relation to self-billing. For these specific flows, a targeted tolerance remains in place until 30 June 2026. This provides additional time for Access Points and ERP systems to finalize the implementation of the Peppol self-billing specifications without the immediate risk of sanctions.

Full Enforcement: Post-Grace Period Status

As of 1 April 2026, the tolerance period is definitively over. All Belgian-established VAT registered businesses must now have the technical capabilities of issuing and receiving B2B invoices in PEPPOL BIS format through the PEPPOL network.

Impact non-compliance

Non-compliance with the e-invoicing obligation carries significant financial consequences. The administration has established a clear penalty escalation system, with penalties ranging up to €5.000.

Next to that, the existing penalties for non-compliance with the invoicing rules, such as late issuance, remain in place.

Furthermore, invalid or non-delivered invoices can cause commercial dissatisfaction and may result in payment delays and disputes, putting your company’s cash flow under pressure.

Action Plan: Compliance & Validation

As we enter the post-transition period, businesses should make sure their systems are properly configured for e-invoicing. The maintenance of accurate master data and correct VAT determination is crucial to the success of your e-invoicing process.

Deloitte’s E-Invoicing Health Check

If your business has implemented Belgian e-invoicing but wants to ensure full compliance and future readiness, Deloitte’s E-Invoicing Health Check is designed for you.

We validate your e-invoicing setup across multiple dimensions, such as:

• Scope validation — identifying which transactions fall within the e invoicing mandate and confirming correct inclusion.

• E invoice validation (AR/AP) — evaluating the completeness, accuracy, and proper processing of structured e invoices on both the sales and purchase sides.

• VAT treatment validation — verifying that the correct VAT codes, tax logic and associated PEPPOL VAT category codes are consistently applied.

• VAT reporting validation — ensuring that VAT relevant data flows accurately and reliably into your VAT returns.

• Solution fit & scalability analysis — assessing whether your current systems and processes are prepared for future e reporting obligations and the evolving ViDA framework.

Our health check provides a clear, pragmatic assessment of your current state and a roadmap for optimization, ensuring you are not only compliant today, but ready for tomorrow’s requirements.

Next Steps

If your business is not yet fully compliant, or if you want to validate your current e-invoicing setup, we recommend acting immediately. Our dedicated team of e-invoicing specialists is here to help.