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·Updated Mar 11, 2026·UBL / Peppol·By Eliel Nicaise

Electronic invoicing with UBL 2.1 and Peppol BIS 3.0

Electronic invoicing is becoming mandatory in many European countries. Discover how the UBL 2.1 format and the Peppol network simplify B2B and B2G exchanges.

Why electronic invoicing?

Electronic invoicing (e-invoicing) replaces paper and PDF invoices with structured XML messages. It reduces processing costs, accelerates payments, and facilitates automated tax controls.

In Europe, Directive 2014/55/EU mandates e-invoicing for public procurement. Many countries are now extending this obligation to the private sector (France, Belgium, Germany...).

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UBL 2.1 invoice structure

A Peppol BIS 3.0 invoice is a UBL 2.1 XML file. Here is a simplified example:

<Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2">
  <ID>INV-2026-001</ID>
  <IssueDate>2026-01-28</IssueDate>
  <DueDate>2026-02-27</DueDate>
  <InvoiceTypeCode>380</InvoiceTypeCode>
  <DocumentCurrencyCode>EUR</DocumentCurrencyCode>
  <AccountingSupplierParty>
    <Party>
      <PartyName><Name>ACME SA</Name></PartyName>
      <EndpointID schemeID="0088">1234567890128</EndpointID>
    </Party>
  </AccountingSupplierParty>
  <LegalMonetaryTotal>
    <TaxExclusiveAmount currencyID="EUR">1000.00</TaxExclusiveAmount>
    <TaxInclusiveAmount currencyID="EUR">1210.00</TaxInclusiveAmount>
    <PayableAmount currencyID="EUR">1210.00</PayableAmount>
  </LegalMonetaryTotal>
</Invoice>

Peppol BIS 3.0 validation rules

Peppol enforces business rules (PINT/BR) in addition to XSD validation:

BR-01

The invoice must have a unique identifier (ID)

BR-04

The issue date is mandatory

BR-CO-15

Total with tax = total without tax + tax amount

BR-S-08

VAT rate must be specified for each taxable line

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Peppol network: how does it work?

Peppol (Pan-European Public Procurement OnLine) is a standardized exchange network. Companies connect through a certified Access Point. Documents are routed via the network using Peppol identifiers (GLN, VAT number...).

To send an invoice on Peppol, your UBL file must comply with BIS 3.0 rules. That's where a validator like ValidateFin becomes essential before sending.

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Validate your UBL invoice

Our UBL / Peppol validator checks structural compliance (XSD) and Peppol BIS 3.0 business rules. View all invoice lines and fix errors before sending.

Validate my UBL invoice

Frequently Asked Questions

What is UBL 2.1 and how does it relate to Peppol?

UBL 2.1 (Universal Business Language) is an XML standard for electronic business documents including invoices and credit notes. Peppol BIS Billing 3.0 is a specification built on top of UBL 2.1 that adds specific business rules for e-invoicing across the Peppol network, implementing the European EN 16931 standard.

What Peppol BIS 3.0 business rules does the validator check?

The validator checks dozens of business rules including: VAT category consistency, line item total calculations, mandatory supplier/buyer identification, payment terms validation, allowance and charge calculations, and document-level total reconciliation.

Can I validate both UBL invoices and credit notes?

Yes. ValidateFin's UBL Validator supports both UBL 2.1 Invoice and Credit Note document types. The same Peppol BIS 3.0 and EN 16931 rules apply to both, with specific rules activated for credit notes.

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