Guides · Updated 10 October 2026

Peppol e-invoicing: what it is and how to check a customer

How the Peppol network works, what a Peppol ID looks like, where e-invoicing is becoming mandatory, and how to see whether a customer can receive one.

What an e-invoice is

An e-invoice isn't a PDF attached to an email. It's a structured file, usually XML, that the customer's accounting software can read and book without anyone retyping it. Across Europe, governments are making them compulsory between businesses, partly to make VAT fraud harder.

How Peppol works

Peppol is a network for sending e-invoices, used most widely in Europe. It works a bit like email: you don't connect to your customer directly. You use a Peppol service provider (an "access point"), often built into your invoicing software, and so does your customer. Your provider looks the customer up in the network's registry, finds their provider, and delivers the invoice.

That lookup is why registration matters: a business can only receive Peppol invoices once its provider has registered it, under a Peppol ID, and listed which formats it accepts.

What a Peppol ID looks like

A Peppol ID is a four-digit scheme code, a colon, and an identifier from that scheme. The same business can be registered under several. Some common ones:

• 9925:BE0417497106: a Belgian VAT number.
• 0208:0417497106: a Belgian enterprise number.
• 0192:123456789: a Norwegian organisation number.
• 0106:12345678: a Dutch Chamber of Commerce (KvK) number.
• 0088:5412345000013: a GLN, a global location number.

Each registration also lists the document types the business accepts, such as Peppol BIS Billing 3.0, the standard European format, or national ones like XRechnung in Germany.

Where e-invoicing is becoming mandatory

• Belgium: since 1 January 2026, invoices between Belgian VAT-registered businesses must be structured e-invoices, sent over Peppol by default.
• Germany: since 2025, every business must be able to receive e-invoices. Sending them becomes compulsory in stages from 2027. Peppol is one accepted route, not the only one.
• France: from September 2026, every business must be able to receive e-invoices through an approved platform, and larger businesses must send them; smaller ones follow in 2027.
• Across the EU: under the VAT in the Digital Age (ViDA) package, e-invoicing and digital reporting become the rule for sales between businesses in different EU countries from July 2030.

Other countries have their own systems and timetables, and the dates have moved before, so check the current rules for each country you invoice into.

Checking a customer before you send

Before you switch a customer to e-invoices, check that they can receive them, under which ID, and in which format. Validitool's free Peppol lookup takes a VAT number, works out every Peppol ID it could be registered under, asks the Peppol network's own registry, and lists the formats the company accepts. If you know the exact Peppol ID, enter that instead.

Not finding a company doesn't mean it can't receive e-invoices: it may be registered under an identifier that can't be worked out from its VAT number, or use a network other than Peppol. Ask the customer for their Peppol ID.

From your own software, use the Peppol lookup API, or get the Peppol status in every compliance check.

This guide is general information, not tax or legal advice. Rules and their application differ by country and by transaction; check with an adviser for your situation.

More guides

• How to check an EU VAT number before you invoice
• VIES is down: what it means and what to do
• The reverse charge explained: EU and UK B2B sales
• How often should you re-check a customer’s VAT number?
• What proof of a VAT number check should you keep?
• EORI numbers explained: EU, GB and XI
• Northern Ireland XI numbers: VAT and EORI
• Checking Swiss and Norwegian VAT numbers
• Sanctions screening for small businesses
• Fake invoices and changed bank details: how to spot supplier fraud