Europe's E-invoicing puzzle: What to know as new mandates go live

A wave of new, complex, and sometimes contradictory e-invoicing regulations is rolling across Europe, and the deadlines are approaching fast. For any business operating in Europe, what once seemed like a distant compliance exercise is now an urgent operational reality. The transition is a core component of the EU's push toward a streamlined Digital Single Market, designed to improve tax transparency and efficiency.

What is the European Union's VIDA (VAT in the Digital Age) initiative?

The VAT in the Digital Age (ViDA) initiative is the European Union’s comprehensive plan to modernize the VAT system through digitalization. Adopted in March 2025, ViDA aims to simplify cross-border trade, reduce fraud, and harmonize e-invoicing and digital reporting across all EU member states.

It introduces a standardized framework for real-time transaction reporting, making e-invoicing the default invoicing system, while allowing countries to align national models with the new rules limiting special exemptions.

Over the next few years, ViDA aims to gradually replace fragmented national systems, ensuring greater transparency, interoperability, and compliance efficiency across the European single market.

What is an e-invoice?

E-invoicing is the fully digital creation, exchange, and processing of invoices in a structured electronic format, such as XML, that allows automated reading and validation by accounting or tax systems

It ensures data accuracy, faster processing, and compliance with fiscal regulations by transmitting invoice information directly between supplier, buyer, andtax authorities.

Is a PDF an electronic invoice?

No, e-invoicing is not simply sending a PDF or scanned document by email. Formats like PDF, TIF, JPEG, or Word are unstructured and require manual input to extract data.

Compliant e-invoicing means machine-readable data, secure transmission, and traceable validation, not just digitized paperwork.

EN 16931 compliance: The European standard for electronic invoices

To create a common "language" for e-invoices, the EU established the European Standard EN 16931. This semantic data model defines the core information an electronic invoice must contain, serving as the foundation for interoperability across Europe.

To make sure that e-invoices are structured, interoperable, and machine-readable, allowing seamless exchange between suppliers, buyers, and public administrations, the standard establishes three mandatory levels of compliance:

• the invoice document level,
• the implementation level,
• and the specification level

At the invoice document level, the electronic invoice must include all required data, use standardized structures and codes, and perform calculations as defined in the core (CORE) model or an approved national variant known as a CIUS (Core Invoice Usage Specification).

The implementation level ensures interoperability, meaning senders must be able to generate compliant invoices, and receivers must be capable of processing any invoice that adheres to the CORE or CIUS model.

Finally, at the specification level, any CIUS must remain fully compatible with the CORE standard, functioning as a subset that doesn’t alter its rules. This guarantees that systems supporting the full CORE model can also process compliant CIUS invoices. Public entities in the EU are legally required, under Directive 2014/55/EU, to receive EN 16931-compliant invoices, promoting a unified and interoperable e-invoicing ecosystem across Europe.

In short, as a business you face the same requirements for content an invoice must contain:

• you need to be able to send and receive invoices
• correctly structure invoices in a safe and secure way
• and the structure of the electronic invoice must be fully compatible with the European Norm (EN16931)

E-invoicing in Europe is no longer a question of "if", but of "when and how"

While the EU provides the overarching framework, individual countries are setting their own aggressive, multi-phased timelines. The direction is clear and the deadlines are firm.

For businesses, the focus must shift from deciding if they will adopt e-invoicing to determining when they must comply and how they will implement the specific technical and process changes required in each market. The staggered, multi-phase deadlines mean businesses must adopt a market-by-market implementation strategy.

Requirements for e-invoicing in Europe: A common goal with fractured rules

Paradoxically, the EU countries do sometimes have different use-cases and practices for electronic invoices. Such domestic invoicing use-cases can be met with an additional layer of country-specific formats and rules on top of it. A format that is compliant in one country may not be sufficient in another.

Poland 🇵🇱

• B2B mandate: February 2026 (Businesses >€46M turnover) April 2026 (All other businesses)
• Format: Strictly mandates its own proprietary XML schema, FA(3), allowing no other formats for B2B transactions.

France 🇫🇷

• B2B mandate: September 2026 (Receiving for all; Issuing for large/mid-size) September 2027 (also Issuing for SMEs)
• Format: Requires that businesses and their Accredited Platforms be capable of processing three distinct formats: UBL, CII, and the national hybrid format, Factur-X.

Belgium 🇧🇪

• B2B mandate: January 2026 (Issuing & Receiving for all businesses)
• Format: Mandates the use of Peppol-BIS as the standard format for all transactions transmitted via the required Peppol network.

Germany 🇩🇪

• B2B mandate: January 2025 (Mandatory receiving for all businesses) January 2027 (Mandatory sending for >€800k turnover) January 2028 (Mandatory sending for all businesses)
• Format: Does not mandate a single format, instead allowing any format that is compliant with the EN 16931 standard. Common examples include XRechnung and ZUGFeRD.

Italy 🇮🇹

• B2B mandate: already in force
• Format: Operates a centralized clearance regime via the Sistema di Interscambio (SdI) and mandates the national FatturaPA XML as the sole valid invoice format for domestic B2B, B2C, and B2G flows; other EN 16931-compliant formats must be converted to FatturaPA for submission

Spain 🇪🇸

• B2B mandate: Once Spain’s technical regulation is officially published, companies with >€8M turnover must comply within 12 months, and all other businesses within 24 months. Many observers anticipate the phased rollout across 2026–2027.
• Format: Spain plans an interoperable model (public + private platforms) that accepts multiple structured formats, notably Facturae, aligned options such as UBL and EDI, and it will coexist with fiscal regulations such as Verifactu, TicketBAI, and NaTicket. Vendors must be able to process and interoperate across these.

Greece 🇬🇷

• B2B mandate: February 2026 (>1M €) October 2026 (all)
• Format: pending

Denmark 🇩🇰

• B2B mandate: January 2026
• Format: Peppol BIS 3.0, OIOUBL

Croatia 🇭🇷

• B2B mandate: January 2026
• Format: PEPPOL BIS 3.0, UBL 2.1, CII

Slovakia 🇸🇰

• B2B mandate: January 2027
• Format: Peppol BIS 3.0, UBL, CII

Portugal 🇵🇹

• B2B mandate: No mandate yet, but from Jan 2026 QR code needs to be embedded in the invoice
• Format: likely CIUS-PT

Sweden 🇸🇪

• B2B mandate: no mandate yet, but widely adopted
• Format: Svefaktura, EDIFACT, Peppol BIS 3.0

Austria 🇦🇹

• B2B mandate: no mandate yet
• Format: ebInterface, Peppol BIS 3.0, CIUS-AT NAT, CIUS-AT GOV

The key takeaway for your business? E-invoicing compliance is not a one-size-fits-all technical solution.

A robust strategy must include a service provider or in-house capability to address the country-specific requirements.

As these deadlines loom, the critical question is no longer if your business will adapt, but how. Have you chosen a strategic partner and developed an organizational roadmap to turn this complex compliance mandate into a competitive advantage?