Belgium's B2B Peppol mandate: a first-month onboarding checklist

Since 1 January 2026, VAT-registered businesses established in Belgium must exchange structured electronic invoices for domestic B2B transactions — in practice, over the Peppol network using the Peppol BIS Billing 3.0 format. A PDF by email no longer satisfies the obligation between two Belgian businesses.

If you are catching up, work through this list. None of it takes long; the point is to do it in order.

1. Register as a Peppol participant

Your business needs to be discoverable on the network under a participant ID — for Belgium, your enterprise number (10 digits, scheme 0208). Registration goes through an access point; in eurobillr this is a two-minute step on the Peppol Network page. You cannot receive a structured invoice until you are on the network, so do this first.

2. Confirm you can receive, not just send

The mandate is symmetric: your suppliers will start sending you structured invoices too. Check that inbound documents land somewhere you actually look — in eurobillr they arrive in the Received inbox and can be turned into expenses in one click. An invoice you cannot receive is an invoice you cannot pay on time.

3. Clean up your client records

Structured invoices are strict. Before your first send, make sure each B2B client has:

• a valid VAT number (we validate it against VIES),
• the correct country code and a real postal address,
• their Peppol participant ID where you have it (often derivable from the

enterprise number).

One afternoon of tidying now prevents a month of rejected documents.

4. Send one real test invoice

Pick a friendly client, issue a genuine invoice, and send it via Peppol. Watch it move from queued to sent to delivered. Seeing the status change is what turns "I think we're compliant" into "we are."

5. Keep the structured reference on your invoices

For Belgian payments, the OGM/VCS structured communication (+++xxx/xxxx/xxxxx+++) lets a bank transfer reconcile automatically. eurobillr prints it on the PDF, embeds it in the Peppol UBL, and encodes it in the SEPA QR — so however your client pays, the payment matches the invoice.

What has not changed

Your VAT rates, your reverse-charge handling for intra-EU B2B, and your Intervat return are unchanged. The mandate is about how the invoice travels, not what it says. Get on the network, tidy your data, send one test — and the mandate becomes a non-event.