E-invoicing in 2026: 3-month tolerance period

Got a tax question? We’ll answer for free by email.

Bitte gib eine gültige E-Mail-Adresse ein

Ask your question

It’s the busiest time of the year. Many self-employed professionals are juggling tight deadlines, buying year-end gifts, and preparing for the Christmas season.

From 1 January 2026, there’s an additional requirement: e-invoicing via Peppol. This is causing stress for many, especially with fines for not switching on time.

In early December, the Belgian tax administration announced a three-month tolerance period. Those who can show they acted on time will get some breathing room… but that doesn’t mean you can wait. You need to take action now.

On this page, we explain step by step what you need to know and do to avoid fines, so you can stay completely worry-free.

E-invoicing: 3-month tolerance period

You may have heard already: there will be a tolerance period from January to March 2026. This means you won’t be fined if you’re not fully ready with Peppol on 1 January 2026. But don’t be mistaken, strict conditions apply.

You will only benefit from the tolerance if:

• You can prove that you made timely and reasonable efforts to comply with the requirement.
• The issue was beyond your control (e.g., a software provider delivering late or a technical problem you couldn’t fix).

You will not get tolerance if:

• You haven’t taken any action.
• You deliberately waited.
• You have no evidence of any effort made.

The government remains strict: Peppol e-invoicing is mandatory from 1 January. But if you act responsibly, you will have some breathing room until the end of March.

What fines do you risk if you don't take action?

From 2026, you may face an administrative fine if you:

• Fail to send e-invoices when required
• Make no effort to activate Peppol
• Persistently continue sending PDFs without a valid reason

The fines increase quickly, so even a single PDF invoice sent the wrong way can end up being costly.

What if you’re ready for Peppol but your client isn’t?

This is likely to become a common scenario in 2026.

You do everything correctly. You send an e-invoice. And your e-invoicing software says: “Client not registered on Peppol.”

Who’s at fault? In principle, it’s your client, not you.

• You are required to be able to send e-invoices.
• Your client is required to be able to receive them.

Tip: In these cases, send your client an email asking them to activate their Peppol inbox. This ensures your collaboration can continue smoothly after 01/01/2026, helps avoid disputes, and shows that you’re meeting your obligations.

Peppol e-invoicing in plain language

E-invoices are digital, structured invoices sent directly from your computer to your client’s system. They are different from a PDF, email, or scan (which are simply digital versions of paper invoices).

Peppol is the network that makes this automatic exchange possible. Think of it as a “postal service for e-invoices”, but faster, paper-free, and error-free.

To send and receive e-invoices, you need e-invoicing software, such as Accountable.

Are you required to follow the e-invoicing rules?

Chances are you are. From 1 January 2026, e-invoicing will be mandatory for:

• All Belgian VAT-registered self-employed professionals (both full-time and part-time)
• Sole proprietorships and companies
• VAT-registered non-profits

These self-employed professionals will need to send e-invoices to other Belgian businesses starting from the new year.

Who is not required to use Peppol e-invoicing?

• Self-employed professionals exempt from VAT due to the nature of their profession (Article 44), such as dentists, psychologists, GPs, etc.

Even if it’s not mandatory, you can still send and receive e-invoices.

From 2026, all invoicing between Belgian VAT-registered self-employed professionals (B2B) must go through Peppol. If you mainly work with private clients (B2C), you don’t have to send e-invoices. But don’t be mistaken: you still need to register on the Peppol network to receive e-invoices from your suppliers.

What you need to do now to stay compliant

Checklist for self-employed professionals:

• Register for Peppol: it’s free and takes just 2 minutes in the Accountable app.
• Send B2B invoices as e-invoices.
• Receive supplier invoices automatically as e-invoices.
• Notice a client isn’t on Peppol after 01/01/2026? Inform them promptly so you don’t get caught out by their delay.

The Peppol plot

• From 1 January 2026, all B2B invoicing in Belgium must be done via Peppol.
• An e-invoice is not a PDF or email, it’s a structured electronic file.
• The tolerance period only applies if you can prove the delay was beyond your control.
• Fines increase quickly: €1,500 for the first offence, €3,000 for the second, and €5,000 for each subsequent violation.
• If you send a correct e-invoice and your client can’t receive it, the fault lies with your client.
• Inform any clients who aren’t set up that they need to activate their Peppol inbox.
• Not ready yourself? Activate Peppol today.

Useful links:

• How to create an e-invoice in Accountable
• E-invoicing and international clients: what you need to know
• How to receive Peppol e-invoices from your suppliers

Peppol e-invoicing with Accountable? It’s really easy. Try Accountable free of charge!

Author - Alexis Eggermont

Alexis is co-founder at Accountable. He is passionate about leveraging data, AI, technology, and entrepreneurship.

Who is Alexis ?