What is Peppol?

 What is Peppol?

Peppol (Pan-European Public Procurement Online) is the dominant e-invoicing network in Europe. It’s a set of open specifications that define how businesses exchange electronic documents — invoices, credit notes, purchase orders — across borders, systems, and formats. Think of it as SMTP for invoices. Your ERP connects to a certified Access Point. The Access Point routes your invoice to the receiver’s Access Point. Both sides speak the same language (Peppol BIS Billing 3.0), regardless of what ERP, accounting system, or country either party operates in. Originally an EU-funded project launched in 2008 for public procurement, Peppol now covers B2B e-invoicing across 39+ countries with 300,000+ registered participants. As of 2026, Belgium, Germany, and Poland mandate Peppol for B2B transactions. France, Spain, and others are adding Peppol support alongside national systems.

How Peppol Works

The Four-Corner Model

Peppol uses a federated architecture called the four-corner model:

Corner 1: The sender (your business or your customer’s ERP)
Corner 2: The sender’s Access Point (certified Peppol service provider)
Corner 3: The receiver’s Access Point
Corner 4: The receiver

The sender’s ERP generates a Peppol BIS invoice and submits it to their Access Point. The Access Point looks up the receiver’s Peppol ID in the network’s directory (SML/SMP), finds the receiver’s Access Point, and delivers the invoice via the AS4 transport protocol. The receiver’s Access Point delivers the invoice to the receiver’s system.

No direct connection between sender and receiver is needed. No bilateral agreements. No format negotiation. As long as both sides have a certified Access Point and a registered Peppol ID, they can exchange documents.

Access Points

An Access Point is a certified service provider that connects your business to the Peppol network. It handles message routing, delivery receipts, and protocol compliance.

Access Points are certified by a Peppol Authority (one per country or region). Certification requires passing conformance tests for message handling, security, and SLA compliance.

As a business, you choose one Access Point. As an ERP vendor, you either become a certified Access Point yourself (significant investment, full control) or you integrate with an existing one via their API.

Most mid-market ERP vendors choose the second option. The Access Point handles the transport; the ERP vendor focuses on generating valid invoices.

Peppol IDs

Every participant on the Peppol network has a unique identifier. The format combines a scheme ID (identifying the type of identifier) with the actual value.

Common scheme IDs:

Scheme	Country	Identifier Type
0208	Belgium	KBO/BCE enterprise number
0106	Netherlands	KvK Chamber of Commerce number
9930	Germany	VAT number (USt-IdNr)
0007	International	GLN (Global Location Number)
0088	International	EAN Location Code
9906	Italy	Codice Fiscale

In UBL, a Peppol ID looks like this:

<cbc:EndpointID schemeID="0208">0123456789</cbc:EndpointID>

Getting the scheme ID wrong is one of the most common integration errors. The scheme must match the identifier type and the country. An invoice with a Dutch KvK number but scheme ID 9930 (German VAT) will be rejected.

SML and SMP (Service Discovery)

The Service Metadata Locator (SML) and Service Metadata Publisher (SMP) form Peppol’s directory system. When an Access Point needs to deliver an invoice, it queries the SML to find which SMP holds the receiver’s metadata, then queries the SMP to get the receiver’s Access Point URL and supported document types.

This happens automatically — you don’t interact with SML/SMP directly unless you’re building an Access Point.

Peppol BIS Billing 3.0

Peppol BIS (Business Interoperability Specification) Billing 3.0 is the invoice format specification. It’s a CIUS (Core Invoice Usage Specification) of EN 16931, meaning it takes the European e-invoicing standard and adds Peppol-specific rules on top.

The underlying syntax is UBL 2.1 (Universal Business Language). An alternative CII syntax exists but UBL is the default for most implementations.

Every Peppol invoice must pass:

1. UBL 2.1 XML schema validation
2. EN 16931 business rules (BR-01 through BR-65)
3. Peppol-specific rules (PEPPOL-EN16931-R001 through R080)
4. Country CIUS rules (if applicable — e.g., XRechnung for Germany, BEvCIUS for Belgium)

The specification identifier that goes in your invoice:

urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0

Full specification: docs.peppol.eu/poacc/billing/3.0

Why Peppol Matters

Where Peppol Is Mandatory (2026)

The mandate landscape is moving fast. Here’s where Peppol stands as of March 2026:

Country	Status	Peppol Role	Details
Belgium	Mandatory B2B (Jan 2026)	Required network	Grace period ended March 31
Germany	Reception mandatory (Jan 2025), sending phased 2027–2028	XRechnung delivered via Peppol	Largest EU market
Poland	KSeF mandatory	Peppol supported alongside KSeF	Dual-track system
France	Phased from Sep 2026	Supported via certified platforms (PDP)	Peppol is one of several options
Italy	FatturaPA mandatory	Peppol growing for cross-border	SDI remains dominant domestically
Netherlands	Voluntary, widely adopted	De facto standard	Highest Peppol adoption in EU
Norway	B2G mandatory	Required for public sector	Early Peppol adopter
Singapore	Nationwide e-invoicing	Peppol-based InvoiceNow	Asia-Pacific expansion
Australia / NZ	B2G pilots	Peppol-based eInvoicing	Growing adoption

 

Why ERP Vendors Need Peppol Support

If you build or maintain an ERP that serves EU businesses, Peppol support is no longer optional in most markets. The question isn’t whether to support it — it’s how to support it without breaking your existing invoice pipeline.

The common pitfall: adding Peppol as an afterthought. ERP generates a PDF or flat file, a converter turns it into UBL, and the result gets pushed to an Access Point. This works until it doesn’t — and it stops working exactly when your customer needs it most (month-end, audit, cross-border transaction with edge-case VAT rules).

The structural approach: validate every invoice against all four rule layers before it reaches the Access Point. Catch schema errors, missing fields, wrong scheme IDs, and rounding mismatches before they become rejections.

That’s what a pre-submission compliance gate does. It sits between your ERP export and the Access Point, and it makes sure nothing leaves your system that would get rejected on the other end.

Common Peppol Validation Errors

These are the errors we see most frequently in production Peppol pipelines:

PEPPOL-EN16931-R010 — Buyer reference is missing or invalid. Required for all Peppol invoices. Maps to BT-10 (Buyer Reference). Many ERPs leave this blank by default.

PEPPOL-EN16931-R001 — Business process identifier missing. The ProfileID element must contain the Peppol BIS 3.0 process identifier.

BR-CO-10 — Sum of invoice line net amounts doesn’t match the total. Usually a rounding issue — especially common with Belgian invoices after the 2026 rounding rule change.

BR-16 — Order reference missing when required. Some country CIUS rules make this mandatory (Germany’s BR-DE-15 requires a buyer reference for public sector invoices).

BR-CO-09 — VAT identifier prefix doesn’t match the country code. The VAT number must start with the correct two-letter country prefix.