EN 16931: the semantic model of the electronic invoice
EN 16931 is the European standard that defines the mandatory data of an electronic invoice. Understanding this semantic model, and why it sits at the heart of the French reform and of the Factur-X, UBL and CII formats.
In this article
In short: EN 16931 says which data an electronic invoice must contain, not how to write it. The three formats of the French reform - Factur-X, UBL and CII - are different ways of carrying that same model. Your job is to provide complete data; your Approved Platform produces the format.
As soon as electronic invoicing comes up, the code EN 16931 is everywhere: in the DGFiP texts, in vendor product sheets, in format documentation. It is in fact the central piece of the framework, and understanding it avoids a lot of confusion between “standard”, “format” and “platform”.
What is the EN 16931 standard?
EN 16931 is a European standard published by CEN (the European Committee for Standardization), in response to Directive 2014/55/EU on electronic invoicing. It defines a semantic invoice model: the list of information an invoice must carry, and the business rules that link them.
It does not describe a layout, nor a specific file. It describes the meaning: a seller, a buyer, lines, VAT rates, totals, references, legal mentions, etc. Each of these pieces is a Business Term (BT-xx), grouped into Business Groups (BG).
The two levels: semantics and syntax
This is the most important distinction, and the one that creates the most misunderstanding.
- The semantic level (what EN 16931 standardizes): which data, with which rules. Universal, independent of the technology.
- The syntactic level: how you write that data in a file. EN 16931 retains two XML syntaxes, UBL and UN/CEFACT CII, plus, in France, Factur-X (a PDF/A-3 that embeds the CII syntax).
In other words: the same invoice compliant with the EN 16931 model can exist as Factur-X, UBL or CII, without losing a single piece of data. The choice of format is a syntax question, not a substance one.
What EN 16931 defines concretely
- The mandatory data: seller and buyer identifiers (including SIRET in France), date, number, currency, lines, quantities, prices, VAT per rate, totals before/after tax, etc.
- The business rules: amount consistency, conditional presence of certain fields, standardized codes (units, VAT categories, etc.).
- The national extension points via the CIUS (Core Invoice Usage Specification), which restrict the standard to a precise use without leaving it.
EN 16931 and the Factur-X / UBL / CII formats
| Factur-X | UBL | CII | |
|---|---|---|---|
| Nature | PDF/A-3 + embedded XML | Pure XML | Pure XML |
| EN 16931 syntax | CII | UBL | CII |
| Human-readable | Yes (the PDF) | No | No |
| Typical use | French merchants, SMBs | PEPPOL network, Europe | International flows, PA-imposed cases |
For the details of each format and the choice per recipient, see Factur-X, UBL, CII: which format to choose.
EN 16931 and the French reform
The French reform relies on EN 16931 as a common foundation: B2B electronic invoices must carry the model’s data, and transit through an Approved Platform (Plateforme Agréée, PA). It is this shared foundation that makes invoices interoperable between companies, whatever their respective platforms.
For the timeline and obligations, see the complete guide to French e-invoicing 2026-2027 and the Approved Platform vs Compatible Solution distinction.
What about Magento?
For a merchant who invoices from Magento, the point is not to “produce EN 16931” by hand, but to ensure that the invoice data is complete and consistent with the model. A Compatible Solution such as Gatebold E-Invoice Gateway extracts the invoice emitted from Magento, normalizes its data against the EN 16931 semantic model, validates it (SIRET, VAT, totals consistency, etc.), then transmits it to the Approved Platform of your choice. The PA then produces the regulatory format (Factur-X, UBL or CII) and delivers it to the recipient.