Factur-X, ZUGFeRD and UBL are European e-invoicing formats. But whichever format an organisation chooses, it must validate the electronic invoices in the same way to ensure they are compliant with the regulation, including the e-invoicing mandate, and their business controls.
Firms must validate the syntax, schematron, receiver’s ID and invoice contents to ensure they are whole and accurate. Alongside a validator for structural compliance, organisations should verify supplier bank account details. Trustpair partners with enterprises to perform these ongoing checks, preventing payment fraud before funds are ever released.
European e-invoicing formats: key takeaways:
- Factur-X, ZUGFeRD and UBL are types of e-invoicing formats used in Germany and France
- E-invoice validation requirements include syntax and schematron checking, as well as making sure all required invoice fields are present and correct
- In Europe, e-invoicing mandates have existed in the B2G sector for over ten years, and individual countries are now starting to mandate B2B e-invoicing too
What are Factur-X, ZUGFeRD and UBL?
Factur-X, ZUGFeRD and UBL are all e-invoicing formats that comply with the European standard EN 16931 under mandatory e-invoicing rules for business-to-government (B2G) transactions.
Factur-X and ZUGFeRD offer the same benefits: hybrid formats that contain both structured XML data for machine readability, and an ordinary PDF format for human understanding. Due to the dual nature of the information contained within the invoices (two xml syntaxes), they can be compliantly and automatically processed through machines, as well as checked by humans.
Factur-X is the French version of the software, while ZUGFeRD serves the German market – which makes this option strong for international trade between organisations from the two countries. The countries’ governments worked on the project together, and simultaneously released their e-invoicing models in January 2026.
A UBL invoice is different because it contains XML file structure only, meaning that it’s strictly for machine-to-machine exchange in systems like Peppol. UBL stands for Universal Business Language, and provides key efficiency and automation benefits as it integrates with business ERP systems. It’s also valid and widely used across both France and Germany.
| E-invoicing comparison | Factur-X / ZUGFeRD | UBL |
| Format | Hybrid: information is converted to both XML code and PDF | XML code/ source code only, no other formats |
| Readability | Readable by both humans and machines | Supports machine readability only |
| Primary usage | B2B invoices and those comfortable with moderate automation | B2G invoices and highly automated systems |
| Compliance | Only compliant with EN 19631 through the correct application | Automatically compliant with EN 19631 |
What are the requirements for validating invoices?
Across Europe, users create invoices for validation under EN 19631 requires checking:
- Whether the syntax or writing is correct, which for UBL is UBL itself, or the hybrid formats, embedded XML containing UN/CEFACT CII
- The schematron: ensuring that the mandatory invoice fields (such as VAT number) are present and free of errors
- The receiver’s Peppol ID or national registry ID (like the French Siren/Siret numbers) to ensure the invoice is being sent to a verified legal entity
- Authenticity and that the data is in tact, often with the feature of electronic signatures
- That they meet minimum interoperability requirements and can integrate into ERP systems
Validation often occurs at the Access Point (AP), with a rest API. If an invoice doesn’t meet EN 16931 standards, the network will bounce it before it’s even delivered to the recipient. Validation reports must be securely stored and archived for up to eight years under the regulation. It effectively replaces the laborous documentation of e mail invoicing with a secure and automated process.
Fortunately for businesses in Germany and France, Factur-X, ZUGFeRD and UBL each automatically validate e-invoices as part of the process. And most businesses perform two or three-way matching against the purchase order, receipt or credit note as part of their wider procurement process. For example, they can validate the line items against real purchases.
Speaking of wider procurement; companies must also secure the payment and contact data embedded within these e-invoices. Otherwise, they operate with a higher exposure to cyberattacks, fraudsters and data breaches. Trustpair is a tool that strengthens digital invoicing processes by verifying supplier bank account details, preventing payment fraud before funds are released.
How does e-invoicing work in Europe?
In Europe, e-invoicing is based on legislation from Directive 2014/55/EU, which has mandated the use of e-invoicing in B2G partnerships since 2014. It means that any organisation invoicing federal governments, national authorities and local councils made the switch to e-invoicing quite some time ago.
Contractors in B2G partnerships may prefer the Peppol network (especially if they’re working across borders), which stands for the Pan-European Public Procurement On-Line. It’s a four-corner model that ensures standardised and secure delivery. Those with cross industry invoice requirements may also choose this route since it is compliant to both B2B and B2G, and has actually extended to use in some parts of Asia.
In Europe, e-invoicing in B2B will become mandated from 2030 onwards, under a new regulation called VAT in the Digital Age (ViDA). However, some countries (like Germany) are already enforcing mandatory B2B e-invoicing; starting with large companies (more than €800,000 revenue) and scaling to businesses of all sizes by 2028. Entities in this sector typically choose their national e-invoice formats, such as Factur-X and ZUGFeRD.
Recapping validation for Factur-X, ZUGFeRD and UBL
Factur-X and ZUGFeRD are the French and German versions of an identical hybrid e-invoice spec (respectively), while UBL is the more generalised, machine-readable only format. Firms must validate their e-invoices to ensure structural compliance. But companies must also secure the payment data embedded within e-invoices: a process aided by Trustpair thanks to automated bank account ownership verification globally.