Check a Belgian customer on Peppol before you send

Peppol participant lookup is a check that a Belgian buyer is findable and can receive invoices before you send. You search scheme 0208 plus the ten-digit enterprise number in your invoicing tool or the Peppol Directory. Success means the network can deliver; it does not mean the buyer accepted your prices.

Example

Atelier Nord copies 0123.456.789 from a contract, strips dots, and looks up 0208:0123456789. The Directory shows BIS Billing receive. The first invoice delivers. A second customer typed without the leading zero: lookup fails until the ten digits are restored.

Why look up before you send

Before you send a structured Peppol invoice, confirm the buyer is findable and able to receive invoices. If they are not, the send fails and the invoice never reaches their systems.

Treat this like checking an IBAN: do it on the first invoice to that customer, after a company change, and whenever a send fails with "participant not found" or similar.

How to verify (in practice)

1. Copy the enterprise number from a reliable source (contract, KBO extract, prior invoice).
2. Use ten digits with leading zeros; remove dots and spaces.
3. In your invoicing software, use verify recipient or check Peppol (best: the same path as a real send).
4. Or search the Peppol Directory with scheme 0208 and that number.
5. Confirm they can receive invoices (not only other document types, if your tool shows that detail).
6. Only then send.

Success means the network can deliver an invoice to that company. It does not mean they accepted your prices, or that every line will book automatically.

Participant lookup

A check in your tool or the Peppol Directory that shows whether a company is findable and can receive invoices on Peppol.

What success and failure look like

Wrong number is the most common miss: missing a leading zero, using a VAT-only string, or invoicing a subsidiary while the parent is registered.

If the customer is not found

1. Double-check the enterprise number with them (ten digits, scheme 0208) and look up again.
2. Ask whether registration is complete and whether they can receive invoices. Point them to Peppol registration in Belgium if they are still onboarding.
3. If they registered minutes ago, wait a bit and look up again.
4. Note the date, identifier, and result for your file under the 2026 B2B rules.
5. Only then consider a controlled fallback: Sending when the client is not on Peppol.

You cannot register your customers for them. They must become findable through their own software or provider.

Where this sits in the journey

1. What is Peppol?
2. Peppol Access Point
3. Registration in Belgium
4. Participant lookup (this article)
5. First Peppol invoice

Make lookup a standard step when you onboard a B2B customer, next to VAT checks. Most first-send failures in Belgium are a wrong number or a customer who is not receive-ready yet.

FAQ

What is Peppol participant lookup?

A check in your tool or the Peppol Directory that shows whether a company is findable and can receive invoices on Peppol.

Which identifier do I search in Belgium?

Scheme 0208 plus the ten-digit enterprise number, with leading zeros. Do not use the VAT string or a branch number as the Peppol ID.

Does a successful lookup mean the invoice is booked?

No. It means the network can deliver an invoice. Acceptance, booking, and IMR are later steps.

What if lookup fails?

Recheck the ten digits first. Then ask whether receive is live. Only then consider a controlled fallback if they are still off-network.

When should I look up again?

First invoice to that customer, after a company change, and whenever a send fails with participant not found.

Related reading

• Peppol ID explained
• Your first Peppol invoice
• Send when the client is not on Peppol
• Share your Peppol ID with suppliers