Peppol 2026: mandatory B2B e-invoicing in Belgium, explained

For years, "e-invoicing" in Belgium meant a PDF attached to an email. That era is ending. Under the new B2B mandate, invoices must be exchanged as structured data over the Peppol network — machine-readable documents that move directly from one accounting system to another, with no re-keying in between.

This is not a soft recommendation. It is a dated, legal obligation, and it lands on nearly every Belgian company at once. For the fiduciaires who serve them, that means a wave of new document formats arriving from day one.

What actually changes in January 2026

Three things shift at the same time:

• The format. Invoices move to the Peppol BIS structured standard — not a scanned image, but typed fields a system can read directly.
• The channel. Documents travel over the Peppol network between registered access points, rather than as email attachments.
• The expectation. Because the data is structured, clients will expect their accountant to process it faster and more accurately than ever.

Why this is hard for small firms

A structured invoice is only useful if your accounting system can read it, code it to the right accounts and VAT grids, and post it. Many small fiduciaires still process bills semi-manually: OCR a PDF, key in the lines, have an accountant review. That workflow does not get easier just because the input is now structured — unless the tooling around it changes too.

The risk is a paradox: more standardised invoices, but the same manual bottleneck downstream. Volume goes up; capacity does not.

How to prepare — practically

1. Make sure your system speaks Peppol

If you run Odoo, structured e-invoicing support is part of the platform. The first step is simply confirming your databases are configured to send and receive over Peppol before the deadline, not after.

2. Decide how invoices get coded

This is where the time is won or lost. A structured invoice still has to be mapped to the correct chart-of-accounts entries and VAT treatment. Doing that by hand for every bill, across every client, is exactly the work that does not scale.

3. Put a human in the loop — not on the assembly line

The goal is not to remove the accountant's judgement; it is to remove the keystrokes. The right setup drafts each bill automatically and surfaces only the ones that genuinely need a decision.

Where Counzel fits

Counzel reads incoming structured invoices inside your Odoo, drafts each one into the right accounts and Belgian VAT grids — learning from your own past entries — and routes them through a Review Inbox with three lanes: posted automatically, ready to review, and exceptions. Every exception explains itself in plain language. You approve; nothing posts unseen.

The Peppol wave is coming either way. The question is whether each new invoice costs your firm a few minutes of data entry, or a few seconds of review.