Factur-X Format Guide: How French B2B E-Invoices Work (UBL, CII & Factur-X Compared)

What Is Factur-X?

Factur-X is a hybrid invoice format. That single word, hybrid, explains almost everything about why it exists and why it has gained so much traction in France.

A traditional invoice is a PDF: easy for a human to read, but useless to a machine that needs to extract the total, the VAT, or the due date. A pure data file like XML is the opposite: a machine reads it instantly, but a person staring at raw tags learns nothing.

Factur-X solves both problems at once. Each Factur-X invoice is a standard PDF/A-3 file with a structured XML data file embedded inside it, conventionally named factur-x.xml. The accounts payable clerk opens the PDF and sees a normal, readable invoice. The accounting system opens the same file and reads the embedded XML to capture every field automatically. One file serves both audiences.

This is why Factur-X is the practical choice for most French businesses. It retains a human-readable PDF that fits naturally into existing email and document workflows, so your customers face no process change, while the structured data underneath satisfies the mandate.

Why France Is Mandating E-Invoicing

The push toward Factur-X is tied directly to France's facture électronique mandate, grounded in Article 153 of the 2020 Finance Law and operationalized by the DGFiP, the French tax authority. The government wants structured invoice data for two reasons: closing a VAT gap estimated at well over 10 billion euros a year, and reducing the administrative cost of processing billions of invoices.

To make that work, France is moving from a post-audit model to a Continuous Transaction Controls (CTC) model. Invoices can no longer arrive in a hundred different layouts sent by email. They must flow through approved channels in one of a few permitted formats, and selected invoice and payment data is transmitted to the DGFiP in near real time.

The reform has two parallel obligations that are easy to confuse:

• E-invoicing covers domestic B2B transactions. The structured invoice itself is exchanged between businesses through approved platforms.
• E-reporting covers transactions that fall outside domestic B2B, mainly B2C sales and cross-border B2B trade. Here you do not exchange a French e-invoice with the counterparty, but you must still report the transaction and payment data to the tax authority.

Both obligations share the same rollout calendar.

The French E-Invoicing Timeline

The mandate rolls out in two main waves, tied to company size:

• 1 September 2026. All businesses operating in France, regardless of size, must be able to receive e-invoices. From the same date, large enterprises and mid-sized companies (ETI) must also issue e-invoices and perform e-reporting.
• 1 September 2027. Small and medium enterprises (PME) and micro-businesses (TPE) must issue e-invoices and comply with e-reporting.

The April 2025 vote in the French National Assembly rejected a proposed further delay, so the September 2026 start date is firm. After full rollout, plain PDFs and paper invoices will no longer be valid e-invoices for fiscal purposes. Invoices must also be archived for the required retention period with guaranteed integrity.

How Invoices Move: The PPF, PDPs, and the Y-Model

Knowing the format is only half the picture. You also need to know the rails the invoice travels on. France originally designed a "Y-model" with two routes to compliance: the public portal and certified private platforms.

The PPF (Portail Public de Facturation), the public invoicing portal, was meant to be a free central hub through which any business could send and receive. Following DGFiP announcements at the end of 2024, the PPF's role was scaled back. It now functions primarily as the national directory (the Annuaire) and the data concentrator that collects invoicing, transaction, and payment data for the tax authority. It no longer offers a universal send-and-receive service.

A PDP (Plateforme de Dématérialisation Partenaire), recently renamed in official specifications to PA (Plateforme Agréée), is a private platform certified by the DGFiP. PDPs format, validate, transmit, and route invoices between trading partners and forward the required data to the tax administration. Because the PPF no longer handles invoice delivery, in practice almost every business will need to work with a certified PDP to exchange B2B invoices. More than 100 PDPs had been registered by the DGFiP as of early 2026.

A core requirement of the model is the exchange of standardized invoice lifecycle statuses, such as deposited, received, approved or rejected, payment due, and payment done. These statuses are what let the DGFiP move toward pre-filling VAT returns from real invoice flows.

Chorus Pro: The B2G Platform That Came First

Many people first encounter French e-invoicing through Chorus Pro, and it is worth being clear about how it relates to the new mandate.

Chorus Pro is the government platform for business-to-government (B2G) invoicing, operated by AIFE, the French state IT finance agency. It has been mandatory for invoices to French public bodies since 2020, making France one of the earliest EU adopters of compulsory B2G e-invoicing. Chorus Pro already accepts Factur-X, UBL, and CII. Submitting it requires correct French identifiers, notably your 14-digit SIRET number and, for public-sector routing, a service code (code de service) that directs the invoice to the right department.

The key point: Chorus Pro (B2G) and the new B2B mandate operate independently. Being set up for one does not make you compliant with the other. The two systems run in parallel, even though both rely on the same underlying formats.

The Three Formats: UBL, CII, and Factur-X

Here is where most people get confused. UBL, CII, and Factur-X are talked about as if they are three competing choices, but they do not sit at the same level. Understanding the relationship is the key to understanding French e-invoicing. All three are valid under the mandate, and all three are built on the same European standard, EN 16931.

UBL (Universal Business Language)

UBL is an XML-based standard maintained by OASIS. It defines a wide library of business documents, and in invoicing it is one of the two XML syntaxes approved under EN 16931. France accepts UBL 2.1. A UBL invoice is pure structured data with no human-readable layer by default. It is widely used across Europe, particularly in public procurement through the Peppol network, and Peppol uses UBL exclusively.

CII (Cross Industry Invoice)

CII is the other approved XML syntax, developed by UN/CEFACT, and it is the syntax that sits underneath Factur-X. Like UBL, a raw CII file is structured data with no visual presentation layer. The practical difference between UBL and CII is mostly which standards body designed the tag structure and how fields are named and nested. For example, seller details live in different elements in each. Both express the same EN 16931 data model.

Factur-X

Factur-X is not a third XML syntax competing with the other two. It is a packaging format. Specifically, it wraps a CII XML file inside a PDF/A-3 document.

So the lineage is: EN 16931 defines the meaning of the data, CII provides the XML syntax to express it, and Factur-X delivers that CII file inside a readable PDF. When someone says they received a Factur-X invoice, they received a PDF with CII data baked in.

Factur-X is the French name. The identical specification is known as ZUGFeRD in Germany, and from version 2.x onward the two are technically interchangeable. The same EN 16931 Schematron rules validate either. The differences are mostly naming conventions and country-specific fields, such as the French SIRET and code de service, or Germany's separate XRechnung profile.

How the Three Compare at a Glance

Aspect	UBL	CII	Factur-X
What it is	XML syntax	XML syntax	Hybrid PDF + embedded CII XML
Human-readable	No	No	Yes (the PDF layer)
Machine-readable	Yes	Yes	Yes (the XML layer)
Underlying data model	EN 16931	EN 16931	EN 16931
Standards body	OASIS	UN/CEFACT	FNFE-MPE (France)
German equivalent	None	None	ZUGFeRD
Best fit	Peppol, public procurement, systems already on UBL	Systems standardized on CII	French B2B where humans still review invoices

Inside a Factur-X File: The Five Profiles

A Factur-X file has a deliberate internal structure. The outer container is a PDF/A-3, an archival PDF standard chosen because it permits embedded attachments and guarantees long-term readability. Inside lives the CII XML, declared in the PDF's XMP metadata so systems know which profile to expect.

Factur-X defines five profiles in increasing order of data richness:

• MINIMUM. Header data and document-level totals only, with no line items. Originally aligned with the basic requirements of Chorus Pro. It is not EN 16931 compliant because it omits line-level detail.
• BASIC WL (Without Lines). Adds richer header information such as payment terms and header-level tax breakdowns, still without individual line items.
• BASIC. Adds line items and covers the common needs of straightforward B2B invoices.
• EN 16931 (also called Comfort). Corresponds exactly to the full EN 16931 semantic model, with complete line-level detail. This is the profile most French businesses should use.
• EXTENDED. Everything in EN 16931 plus additional structures for complex cases such as sub-lines, useful for manufacturing and logistics.

For most French businesses, the EN 16931 profile is the safe default. It satisfies Chorus Pro, is accepted by all PDPs, works for cross-border EU trade, and carries the complete structured data that automated AP systems can process without manual intervention. The profile system exists so businesses can adopt gradually, but the readable PDF stays intact at every level.

Which Format Should You Use?

The honest answer is that the choice is often shaped by the mandate, your trading partners, and your software. Still, a few principles help.

If your business or your customers still rely on people visually checking invoices, Factur-X is the natural fit because it keeps the document readable while adding automation underneath. This describes most French B2B sellers, which is exactly why Factur-X has become the de facto default.

If you operate heavily through Peppol or in public-sector procurement across Europe, you will encounter UBL frequently, since that ecosystem leans toward it. If your ERP has already standardized on CII data, staying on CII or Factur-X keeps everything consistent. In practice, modern invoicing platforms and PDPs handle conversion between formats, so the real job is making sure the EN 16931 data model is correctly populated. The syntax it travels in becomes a configuration detail.

Preparing Your Business for the 2026 Mandate

Compliance is less about picking a favorite format and more about readiness. A practical checklist:

• Confirm you can receive e-invoices by September 2026. This applies to every business operating in France from day one, regardless of size.
• Select and onboard a PDP early. Since the PPF will not provide universal send-and-receive, a certified Plateforme de Dématérialisation Partenaire is the route most businesses need. Onboarding, testing, and ERP integration take time.
• Confirm the profile your customers and PDP require. EN 16931 is the safe default for French B2B.
• Clean your master data. Structured formats are unforgiving about missing mandatory fields, and French-specific values like the SIRET (14 digits) must be correct or invoices get rejected.
• Validate before going live. Run your output through a Factur-X validator to check the XML against EN 16931 rules and confirm PDF/A-3 conformance before your first real submission.
• Map your e-reporting obligations. If you have B2C or cross-border B2B transactions, you have reporting duties even where no French e-invoice is exchanged.

The earlier you test with real trading partners, the fewer surprises you face when issuance becomes mandatory for your size band.

The Bottom Line

Factur-X works because it refuses to force a choice between human and machine. The PDF keeps the invoice readable for the people who still review them; the embedded CII XML feeds the systems that automate them. UBL and CII are the underlying XML languages that express invoice data, while Factur-X is the hybrid package that delivers CII data inside a familiar document. All three rest on EN 16931.

For most businesses selling into France, Factur-X at the EN 16931 profile is the practical starting point and the format you will meet most often. Get your data clean, choose a certified PDP, confirm your software speaks the standard, and the transition to mandatory France e-invoicing in September 2026 becomes a manageable upgrade rather than a scramble.

For a closer look at how the French mandate works and how to prepare your invoicing for September 2026, visit us!