Peppol Messages Explained: What They Are, and What’s Different in France, Belgium, and Poland

By the middle of 2026, three of Babelway’s core markets moved from “e-invoicing mandate coming soon” to “e-invoicing mandate live.” Belgium’s B2B Peppol requirement has been in force since January 1, 2026. France’s obligation for large and mid-sized companies starts September 1, 2026. Poland’s KSeF mandate is rolling out between February and April 2026. All three lean on the same underlying technology: Peppol. If you trade across any of these markets, understanding how Peppol messages actually work, not just that they’re required, is what separates a smooth rollout from a scramble in Q3.

What Is Peppol, Exactly?

Peppol (Pan-European Public Procurement Online) is an international network and set of specifications that let businesses and public authorities exchange structured business documents the same way, regardless of which software or country they use. Instead of negotiating a bespoke connection with every trading partner, you connect once to the Peppol network through a certified Peppol Access Point, like Babelway, and you can reach every other participant already on it.

Peppol now spans dozens of countries and well over a million connected participants, and it covers far more than invoices: purchase orders, catalogues, and shipping notices all travel over the same network using the same discovery and transport model.

The Message Types That Matter for E-Invoicing

• Invoice (Peppol BIS Billing 3.0): the standard electronic invoice message, built on UBL 2.1 XML and aligned with the EN 16931 European standard.
• Credit Note: the standardized message for corrections, adjustments, and refunds tied to a previously issued invoice.
• Message Level Response (MLR): a technical acknowledgment confirming a message was received and passed validation, or explaining why it didn’t.
• Invoice Response: a business-level message indicating whether the buyer accepts, disputes, or is still processing the invoice.

Each message type follows a strict schema. That rigidity is the point: it’s what lets an invoice generated in a French ERP be read automatically by a Belgian buyer’s accounting system, with no manual re-keying and no PDF parsing.

How a Message Actually Travels: The Four-Corner Model

Peppol messages move through four “corners.” C1 is the seller, who sends the invoice to C2, their own Access Point. C2 uses Peppol’s central directory (the SML/SMP discovery layer) to find the buyer’s Access Point, C3, and delivers the message over the AS4 transport protocol. C3 then hands the invoice to C4, the buyer. Neither party needs a direct integration with the other; each just needs a certified Access Point, and the network handles the rest.

Where the Mandates Diverge: Belgium, France, and Poland

Peppol is the common thread, but each country has built its own compliance model on top of it. Here’s the shape of each mandate as it stands in July 2026.

Belgium: Peppol Is No Longer Optional

• Mandatory since January 1, 2026 for all VAT-registered businesses on domestic B2B transactions.
• A tolerance period ran through March 31, 2026; penalties of €1,500 / €3,000 / €5,000 have applied since April 1, 2026.
• PDF invoices sent by email no longer satisfy the obligation. Invoices must be structured and sent via Peppol.
• The default format is Peppol BIS Billing 3.0 (UBL 2.1), aligned with EN 16931. See eInvoicing in Belgium for the European Commission’s overview.
• Peppol is also expected to underpin Belgium’s near-real-time e-reporting system, planned for 2028 as part of the EU’s ViDA initiative.

Babelway has been a certified Peppol Access Point since 2014, and our infrastructure is trusted by the Belgian and Luxembourg governments for their own public e-invoicing platforms, so Belgian compliance was never a bolt-on for us. See how Yonderland connected to Peppol with Babelway in our case study.

France: Peppol as the Connective Tissue Between Accredited Platforms

• From September 1, 2026, large and mid-sized (ETI) companies must issue e-invoices; every VAT-registered business in France must be able to receive them from that date. SMBs and micro-enterprises follow through 2027.
• Unlike Belgium, France doesn’t route invoices peer-to-peer over Peppol. Invoices pass through registered Plateformes Agréées (PA), previously known as PDPs, which validate, enrich, and route documents, and report transaction data to the French tax authority, DGFiP.
• DGFiP was formally designated France’s national Peppol Authority in July 2025, with responsibility for governing how Peppol is used inside the French model.
• Most PAs, including Babelway, are also Peppol Access Points, so Peppol BIS Billing 3.0 is the common transport layer whenever invoices cross between PAs or borders. Domestically, formats also include Factur-X and CII.
• Enforcement is expected to be lenient at first: the DGFiP has signaled there will be no “automatic and blind sanctions” from day one, but the receiving obligation and the requirement to connect through a PA still apply from September 1.

Babelway itself holds permanent registration as a Plateforme Agréée in France, which means outbound compliance for companies with modest invoice volumes can go live without an ERP overhaul. Read more in How to Send and Receive Compliant E-Invoices in France in 2026.

Poland: KSeF Adopts the Peppol Message Model, With Local Rules

• February 1, 2026: mandatory for large taxpayers, defined as those with annual turnover above 200 million PLN (roughly €46 million).
• April 1, 2026: mandatory for all other B2B taxpayers.
• Invoices use Poland’s FA(3) schema, broadly aligned with the EN 16931 and Peppol BIS 3.0 structure but with Poland-specific VAT fields, so it isn’t a drop-in replacement for a generic Peppol invoice.
• Separately, Poland’s B2G platform (PEF) already accepts invoices in plain Peppol BIS Billing 3.0 UBL format, and Peppol is expected to keep supporting cross-border interoperability alongside KSeF.
• A grace period means no financial penalties for KSeF non-compliance before January 1, 2027: useful breathing room, but not a reason to delay integration work.

What This Means If You Trade Across All Three

Same underlying grammar, three different implementations. Treat this as one connectivity project, not three separate ones:

• One format engine that can produce and consume Peppol BIS Billing 3.0, France’s Factur-X and CII, and Poland’s FA(3).
• One connectivity layer that reaches Belgium’s Peppol network, France’s PA ecosystem, and Poland’s KSeF and PEF.
• One place to track delivery status and validation failures across all three markets, instead of three separate dashboards.

How Babelway Helps

Babelway is a certified Peppol Access Point and a permanently registered Plateforme Agréée in France, and our platform is trusted by the Belgian and Luxembourg governments for their public e-invoicing infrastructure. We convert your ERP’s native format into whatever a given mandate requires, route it over the right network, and give you one place to monitor delivery across markets, without you needing to become an expert in UBL schemas or PA architecture.

If Belgium, France, or Poland (or all three) are in scope for your business this year, the earlier you connect, the more time you have to test before the deadlines that matter to you actually arrive.

Start your 30-day free trial of Babelway

Further Reading on the Babelway Blog

• How Belgian SMBs Can Prepare for the 2026 E-Invoicing Mandate with Babelway
• How to Send and Receive Compliant E-Invoices in France in 2026, and When Babelway Is the Right PA
• EDI, B2B Integration, and Peppol: A Guide to Easy Document Exchange
• Meet Babelway at Peppol Conference Europe 2026 in Brussels
• Case study: Yonderland Frees Employees for Strategic Work with Babelway’s EDI and Peppol Connection