The pure-PEPPOL model

When a country moves to electronic invoicing, it has two options: invent its own format (like France with Factur-X or Italy with FatturaPA) or adopt the shared European standard as-is, PEPPOL BIS Billing 3.0. Luxembourg chose the second path — and only the second. For a small, multilingual state where most trade crosses a border, betting on the European network rather than a home-grown standard was the rational bet. Think of PEPPOL as a shared postal network: everyone uses the same stamp, and the letter arrives anywhere in Europe.

History — the choice not to build a national format

Several large countries built a centralised national infrastructure: Italy routes all its invoices through the Sistema di Interscambio (SdI), France through Chorus Pro and then the public invoicing portal. These choices are justified by domestic market size: there is enough domestic volume to amortise a dedicated format and platform.

Luxembourg lacks that volume. With ~660,000 inhabitants but an ultra-internationalised economy (financial centre, industrial headquarters, Belgian, French and German cross-border workforce), most invoicing flows have a counterparty across a border. Building a Luxembourg FatturaPA would have forced every foreign partner to support one more format. By adopting PEPPOL as-is, Luxembourg plugged into a network already used by dozens of national authorities.

PEPPOL "four-corner" model

  C1 ─────────► C2 ─────────► C3 ─────────► C4
 Sender       Sender's        Receiver's     Receiver
(supplier)    Access Point   Access Point   (LU state /
                                             company)

  C1  The supplier creates the PEPPOL BIS 3.0 invoice (UBL 2.1).
  C2  Its access point signs it and sends it over AS4.
  C3  The receiver's access point (CTIE for the state) receives it.
  C4  The receiver processes it in its accounting.

  Directory:  SML (Service Metadata Locator) — PEPPOL DNS root
              SMP (Service Metadata Publisher) — receiver capabilities
  Routing  :  EndpointID + schemeID (ICD 0240 = LU matricule)
  Transport:  AS4 (ebMS 3.0) encrypted + signed end to end

Governance — OpenPEPPOL and the Luxembourg authority

PEPPOL is governed by OpenPEPPOL AISBL, a Belgian-law association that publishes the BIS specifications and accredits access points. Each country appoints a national PEPPOL Authority that supervises operators in its territory. In Luxembourg, the operational role falls to the CTIE, which runs the state's access point and liaises with OpenPEPPOL.

The governance advantage is clear: Luxembourg maintains no XSD schema, Schematron rules or proprietary portal to evolve with every release. It consumes the OpenPEPPOL roadmap (two validation-rule versions per year) and merely adapts national routing.

PEPPOL architecture — four corners, AS4, SMP/SML

The Luxembourg "format" boils down to two identifiers in the UBL header: the CustomizationID declaring PEPPOL BIS 3.0 conformance, and the EndpointID carrying the receiver's matricule. Everything else — encryption, directory, acknowledgements — is handled by the network.

<!-- Luxembourg's only "format": PEPPOL BIS Billing 3.0 -->
<cbc:CustomizationID>
  urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0
</cbc:CustomizationID>
<cbc:ProfileID>
  urn:fdc:peppol.eu:2017:poacc:billing:01:1.0
</cbc:ProfileID>

<!-- Routing: no proprietary address, just a PEPPOL identifier -->
<cac:AccountingCustomerParty>
  <cac:Party>
    <cbc:EndpointID schemeID="0240">00000000000</cbc:EndpointID>
  </cac:Party>
</cac:AccountingCustomerParty>

Pure PEPPOL vs national format

Why it works for Luxembourg

• Small market, great openness. Most invoices have a cross-border counterparty — interoperability beats format sovereignty.
• Native multilingualism. PEPPOL is language-neutral; no need to impose FR, DE or LB in the format.
• Pooled IT cost. Luxembourg does not fund the development of a format or a dedicated national platform.
• ViDA-ready base. The pure-PEPPOL B2G foundation is directly reusable for the future European Digital Reporting.

Common pitfalls

• Looking for a "Luxembourg format". There is none. The format is PEPPOL BIS Billing 3.0, identical to Norway's, Sweden's or the Netherlands'.
• Trying to route without an access point. You don't send a PEPPOL invoice over SMTP: you must go through an accredited Access Point (your own or a provider's).
• Ignoring the receiver's SMP. Before issuing, the sender queries the SMP to check the receiver accepts the invoice profile — otherwise delivery fails.
• Confusing EN 16931 and PEPPOL BIS. EN 16931 is the semantics; PEPPOL BIS 3.0 is the implementation specification (CIUS + transport rules). Luxembourg mandates the latter.

Cross-links

• Luxembourg hub — full view
• B2G PEPPOL — act of 13 December 2021
• Matricule & RCSL — identifiers
• CTIE — multilingual eGovernment
• ViDA & Luxembourg 2030
• OpenPEPPOL — BIS Billing 3.0 spec
• PEPPOL Authorities