E-invoicing grace period in Belgium: three-month tolerance in 2026

Belgium confirmed on Dec. 2, 2025, that a three-month e-invoicing grace period is in place for the new B2B e-invoicing obligation to take effect on Jan. 1, 2026. So the obligation will continue as usual. The grace period is not a delay, but a temporary enforcement tolerance for companies that are demonstrably implementing structured e-invoicing.

This development is relevant for Belgian companies and for Dutch companies that have Belgian branches or do a lot of business with Belgian parties.

What does the e-invoicing grace period entail?

The e-invoicing grace period runs from Jan. 1 to March 31, 2026, meaning that a second or subsequent violation can only be detected after a minimum of three months. The obligation itself remains in full force: the structured e-invoice will be the only valid B2B invoice between Belgian VAT-registered companies as of Jan. 1.

In doing so, FPS Finance confirmed that there will be no postponement, but there will be a tolerance period for companies that can prove that they acted in a timely and reasonable manner. As VRT NWS reports, “It has been decided to introduce a tolerance for companies that are not in order on Jan. 1, if they prove that circumstances prevented them from doing so.”

So this e-invoicing grace period does not change the deadline, but it does change the way the tax authorities enforce the first few months.

What fines apply?

The following penalties apply for non-compliance:

• First offense: €1,500
• Second offense: €3,000 (only after a minimum of three months)
• Third and subsequent offenses: €5,000 (also with interval)

The three-month interval prevents companies actively working on their implementation from incurring multiple penalties in quick succession. So the e-invoicing grace period does not make fines disappear, but it does give you time to fix errors if you are demonstrably in transition.

What will change as of Jan. 1, 2026?

As of Jan. 1, 2026, in Belgium:

• B2B invoices between Belgian VAT-registered companies must be structured e-invoices.
• The format must comply with EN16931, in practice usually Peppol BIS / UBL.
• PDFs and paper invoices no longer count as valid e-invoices for B2B transactions.

The obligation covers domestic B2B transactions between Belgian VAT numbers. The structured e-invoice thus becomes the basis for the business invoice flow in Belgium.

To whom does the obligation apply?

The e-invoicing requirement applies to:

• Belgian companies with a Belgian VAT number,
• including foreign companies with a permanent establishment or branch in Belgium.

The obligation does not apply to:

• foreign companies with no Belgian establishment or Belgian VAT registration,
• even when they invoice Belgian customers from abroad.

In those cases, a Belgian customer may of course request e-invoicing via Peppol, but that is a contractual agreement, not a legal obligation.

Can you still send PDF invoices during the e-invoicing grace period?

During the e-invoicing grace period:

• the structured e-invoice remains the only legally valid B2B invoice;
• a PDF may be used temporarily as a practical fallback, but only when you are clearly working on your technical implementation.

So this is a limited, temporary tolerance. This is not a formal extension of the old way of doing things, but a way in which the tax authorities want the transition to be careful.

What does this mean for Dutch companies?

You must take into account the Belgian obligation when:

1. You have a Belgian branch or permanent establishment.
   In that case, you are fully subject to the Belgian e-invoicing obligation.
   
   
2. You receive invoices from Belgian suppliers.
   They must send you structured e-invoices from 2026; you must be able to process them technically.
   
   
3. You have Belgian entities within an international group.
   Every entity with a Belgian VAT number must be compliant by January 1, 2026.
   

Do you invoice Belgian customers from the Netherlands without a Belgian branch office?
Then you are not subject to the legal obligation, but Belgian customers can require structured e-invoices from you via Peppol for their own processes.

What should you do now?

Our role: how we help organizations with inbound e-invoicing

The new requirement is not only about sending structured e-invoices, but also about receiving and processing them. What many organizations run into is that incoming e-invoices:

• arrive in UBL or Peppol format,
• need technical validation,
• should be automatically linked to purchasing or accounting processes,
• and should be processed without errors.

This is exactly what we help companies with every day.

Our software supports:

• automatic processing of incoming e-invoices through Peppol,
• validation and interpretation of UBL structures,
• Seamless interfacing with ERP and financial systems,
• as well as a robust process for document capture and audit trail.

In other words, we ensure that organizations are not only compliant, but also operationally ready for the new way of invoicing in Belgium.

Conclusie

Belgium’s B2B e-invoicing obligation goes into effect unabated on Jan. 1, 2026. The e-invoicing grace period only ensures that companies do not face multiple fines in succession immediately.

For organizations with Belgian branches or intensive trade relations with Belgian companies, this is a significant topicality that requires immediate action.

Frequently asked questions about Peppol and the e-invoicing grace period