E-invoicing 2026: making your business software compliant

The mandatory e-invoicing reform is no longer a distant deadline: it takes effect in September 2026. For companies running custom business software or a custom ERP, the challenge is not to switch tools, but to turn the existing system into a compliant node of the French tax network by integrating APIs and handling structured data flows.

What the reform really changes: 2026-2027 timeline and obligations

Mandatory electronic invoicing (or e-invoicing) is a structural reform that aims to digitize the entire lifecycle of an invoice for transactions between VAT-registered businesses in France. It goes beyond sending a digital document; it requires the systematic transmission of structured data to the tax authorities.

The rollout follows a strict timeline in two major phases:

1. September 1, 2026: this is the "Big Bang" for receiving invoices. Every French company, without exception (from sole proprietorships to large groups), must be able to receive compliant electronic invoices. For issuing invoices, only large companies and ETIs (French mid-cap companies) are concerned on that date.
2. September 1, 2027: the obligation to issue e-invoices extends to SMBs, very small businesses and micro-enterprises. At the same time, e-reporting also becomes mandatory. Unlike e-invoicing (domestic B2B), e-reporting covers the transmission of transaction data that falls outside the scope of e-invoicing: sales to consumers (B2C), international transactions (import/export) and payment data.

At Fragments Studio, we see that many executives view this as an accounting constraint. Technically, it is first and foremost an interoperability challenge. Your business software now has to speak a universal, standardized language.

PA, Factur-X, UBL: compliance vocabulary without the jargon

To navigate this reform, it is crucial to understand the technical building blocks that make up the new tax landscape.

• PA (Plateforme Agréée, formerly PDP): the term PDP stood for Plateforme de Dématérialisation Partenaire (partner dematerialization platform). We now talk about a PA, meaning a state-approved platform that acts as a secure intermediary between your software and the tax authorities. Since the public portal was dropped as the single transit point, the PA has become the central pivot. It validates your invoices, converts them into the legal format and sends them to the recipient while notifying the tax authorities.
• Factur-X: this is the standard format in France. It is a "hybrid" invoice: a PDF file readable by the human eye that invisibly contains a structured XML file readable by machines.
• UBL and CII: these are the two other structured data formats accepted by the reform, based exclusively on XML code, with no attached PDF visual.
• Central Directory (Annuaire Central): a state-run registry that lists every company and the PA (formerly PDP) it uses. Before sending an invoice, your system will query this directory to find out where to send it.

The challenge for your custom business software is to be able to generate Factur-X natively to avoid any break in the flow.

Why emailing PDFs is now prohibited

The format we all know (sending a plain PDF by email) becomes illegal for B2B transactions starting in September 2026.

A standard PDF is "unstructured" data: a machine cannot extract the VAT amount or the SIRET number (French company identification number) without a risk of error (OCR).

The reform imposes three pillars that your current tools probably do not handle yet:

1. Integrity and authenticity: the invoice must be digitally sealed.
2. Lifecycle: an invoice is no longer a static document. It has statuses (submitted, rejected, refused, paid) that must be synchronized in real time between your ERP and the government platform.
3. Transmission through a secure channel: email is no longer a valid channel. Invoices must travel through secure protocols between PAs (formerly PDPs).

If you use a digital tool that can no longer keep up, this reform is the ideal time to consider an in-depth update of your data architecture.

Making your business software compliant: the API approach

Rather than abandoning a high-performing business tool for a generic SaaS (which will not cover your specific needs), the most effective approach is to build a technical bridge. Instead of asking yourself "which new software should I buy", ask yourself "how do I connect my current software to a PA (formerly PDP)".

Step 1: connecting via API

Almost all PAs (formerly PDPs) expose APIs (Application Programming Interfaces). The work consists of developing a module within your business software that will:

• Extract the billing data (service lines, amounts, taxes, customer information).
• Convert it into the Factur-X format.
• Send the API call to the PA (formerly PDP) for delivery.

Step 2: managing the lifecycle

Your interface must now show whether the invoice was received by the customer or rejected by the tax authorities because of a calculation error.

This API integration in your tool lets you automate these status updates without any manual action from your accountants.

Step 3: automating e-reporting

For in-store or export sales, your software must aggregate transactions and push them periodically (roughly every 10 days for most companies) to the PA (formerly PDP) through a dedicated API route.

Fragments Studio's support: audit and deployment

At Fragments Studio, we do not publish accounting software. Our job is to work on your existing code to make it compliant and high-performing, including when it needs to talk to Sage or to an invoicing connector.

Our methodology for e-invoicing 2026 runs in three phases:

1. Data audit: we check that your database contains all the mandatory fields (SIRET, country code, VAT category, etc.). If any are missing, we update your data schema.
2. Connection plan: together, we select the PA (formerly PDP) best suited to your volume and your tech stack, then we design the API connector.
3. Flow update: we code the routines that generate structured files and the status-tracking interface in your current dashboard.

This approach lets you keep control of your tool while keeping your TCO (Total Cost of Ownership) under control: you do not pay for an expensive new per-user software subscription, you pay for a technical update of your own asset.

Penalties and checklist: don't miss the September 2026 turning point

The penalties set by the authorities are dissuasive:

• €15 per non-electronic invoice (capped at €15,000 per year).
• €250 per e-reporting failure.
• But the biggest risk is above all blocked payments: your mid-cap and large-company customers will simply no longer be able to accept your invoices if they are not in the legal format from 2026.

Immediate preparation checklist

• Qualify your customers: how many are VAT-registered businesses in France (e-invoicing) vs consumers or export customers (e-reporting)?
• Audit your SIRET and VAT data: are your customer records and your own company record up to date and complete?
• Choose your PA (formerly PDP): choose your approved platform early, the best ones will be saturated by mid-2026.
• Plan the technical project: a clean integration takes between 2 and 4 months depending on the complexity of your business software.

Frequently asked questions

What is a PA (Plateforme Agréée, formerly PDP)?
A PA is a private operator registered by the tax authorities that handles the issuing, transmission and receipt of structured electronic invoices. It guarantees the compliance of the data sent to the government and interoperability between companies.

Can I keep sending PDF invoices by email?
No. Starting September 1, 2026, sending plain PDFs by email will no longer have legal value for domestic B2B transactions. Invoices will have to go through an approved platform in a structured format such as Factur-X.

What is the difference between e-invoicing and e-reporting?
E-invoicing covers the exchange of structured invoices between French companies (B2B). E-reporting is the mandatory transmission of payment and transaction data for sales to consumers (B2C) or international sales, so that the authorities have a complete view of the VAT collected.

Can my current business software become compliant without changing everything?
Yes, that is the approach we recommend. By developing an API connector and updating the data generation flows, it is entirely possible to make custom software compliant with the 2026-2027 reform without having to migrate to a new ERP.

Conclusion

The mandatory e-invoicing reform is a technical challenge before it is an administrative constraint. In 2026, your ability to get paid will depend directly on the quality of your software integration. Don't let the timeline dictate your pace: turn your business tool into an open, connected system, ready for the new standards of the digital economy.

Bring your software up to standard before September 2026

Don't let technical debt block your invoicing and your cash flow.

• Discover our business software expertise to adapt your existing tools.
• If your project involves updating your data flows, our custom development team can support you.
• Get an initial estimate of your compliance project with our project estimator.
• Or let's talk directly to audit your current code.