âE-invoiceâ sounds like it should mean any invoice sent by email. In tax law, it doesnât. Around the world, governments are making structured electronic invoices mandatory â often routed through, or reported to, a government platform in real time. If you sell to businesses in countries such as Italy, Mexico, India, Poland, Germany or France, these rules already affect you or soon will. This guide explains what an e-invoice is, the common formats, and the state of play in key countries.
E-invoicing rules are changing quickly and timelines are often postponed or adjusted. Dates below reflect rules as adopted or announced at the time of writing; always check the current official guidance. This is general information, not legal or tax advice.
E-invoice vs. PDF invoice
| PDF / emailed invoice | Structured e-invoice | |
|---|---|---|
| Format | A visual document (PDF, image, Word) | Machine-readable data (usually XML, sometimes JSON) |
| Read by | Humans | Software â the buyerâs system can process it automatically |
| Standardised fields | No | Yes â follows a defined schema (e.g. EN 16931, UBL, CII) |
| Transmission | Email, upload, post | Often via a network (e.g. Peppol) or a government platform |
| Government involvement | None | In many countries: validated, cleared or reported to the tax authority |
A plain PDF â even one sent by email â is generally not an e-invoice under mandatory e-invoicing rules. A hybrid format such as ZUGFeRD / Factur-X (a PDF with embedded structured XML) can qualify where accepted, because the XML is the legally relevant part.
The main models
- Post-audit / exchange model: businesses exchange structured e-invoices (often via Peppol), and the tax authority audits later. Example: Belgiumâs B2B mandate, Germanyâs.
- Clearance model: each invoice must be submitted to and validated by a government platform before (or as) it reaches the buyer. Examples: Italy (SdI), Mexico (CFDI), Poland (KSeF), India (IRP for in-scope businesses).
- Real-time reporting: the invoice is exchanged between parties, but invoice data is reported to the authority within a short period. Many countries combine reporting with one of the models above.
Common formats and standards
| Standard / format | Where youâll meet it |
|---|---|
| EN 16931 | European semantic standard for e-invoices; basis for most EU formats |
| UBL and UN/CEFACT CII | XML syntaxes that implement EN 16931 |
| Peppol BIS Billing 3.0 | Invoice format on the Peppol network (Belgium, Nordics, Netherlands, Singapore, Australia/NZ and others) |
| XRechnung | German public-sector format (CIUS of EN 16931) |
| ZUGFeRD / Factur-X | Hybrid PDF + XML, used in Germany and France |
| FatturaPA | Italyâs XML format for the SdI |
| CFDI 4.0 | Mexicoâs XML format |
European Union: ViDA
The EUâs VAT in the Digital Age (ViDA) package was adopted in 2025. Its e-invoicing elements, in summary:
- Member states can now introduce domestic B2B e-invoicing mandates without needing special EU authorisation.
- From 1 July 2030, e-invoicing and near-real-time digital reporting become mandatory for intra-EU B2B transactions, based on the European standard (EN 16931).
- Domestic e-invoicing and reporting systems are expected to converge with the EU model over the following years.
Under ViDA, the EUâs definition of an e-invoice is a structured format that allows automatic processing â a PDF alone wonât qualify.
Germany
Germany introduced B2B e-invoicing for domestic transactions between businesses established in Germany in phases:
- From 1 January 2025: all businesses must be able to receive e-invoices.
- Until end of 2026: paper and non-structured electronic invoices (e.g. PDF) may still be issued; the recipient must agree to receive PDFs.
- From 1 January 2027: businesses with prior-year turnover above âŹ800,000 must issue e-invoices.
- From 1 January 2028: all businesses must issue e-invoices for domestic B2B sales.
Accepted formats include XRechnung and ZUGFeRD (version 2.0.1 or later, excluding the most basic profiles), or other formats compliant with EN 16931 if both parties agree. Exceptions apply to some transactions, such as small-amount invoices (up to âŹ250) and certain tickets. B2C invoices are not covered.
France
Franceâs B2B e-invoicing reform has been postponed before. Under the timeline set out in the 2024 finance law:
- From 1 September 2026: all businesses must be able to receive e-invoices, and large and mid-sized companies must issue them.
- From 1 September 2027: small and micro businesses must also issue e-invoices.
Invoices are exchanged through certified platforms (approved private platforms), and businesses must also e-report transaction and payment data for B2C and international sales. Check the latest official guidance on the phase-in status.
Italy (SdI)
Italy was the first EU country with a general B2B mandate. Since 1 January 2019, most domestic B2B and B2C invoices must be issued as FatturaPA XML files through the governmentâs Sistema di Interscambio (SdI), which validates and delivers them. B2G e-invoicing has been mandatory since 2014â2015. The obligation was extended to most small flat-rate (forfettario) taxpayers from 2024. Invoices that bypass the SdI are generally considered not issued.
Poland (KSeF)
Polandâs National e-Invoicing System (KSeF) is a clearance platform. As announced, mandatory use was phased in during 2026:
- From 1 February 2026: large taxpayers (sales above PLN 200 million in 2024) must issue invoices in KSeF; all businesses must be able to receive them.
- From 1 April 2026: the obligation extends to other businesses.
- Until 1 January 2027: relief for the smallest businesses (those with low monthly invoiced amounts), and transitional relaxation of some penalties.
Each invoice receives a KSeF number when accepted by the system.
Belgium
Belgium made structured B2B e-invoicing mandatory for domestic transactions between VAT-registered businesses from 1 January 2026, with Peppol BIS as the default format, and has announced real-time reporting to follow from 2028.
India
Indiaâs GST e-invoicing requires in-scope businesses to register each B2B invoice on an Invoice Registration Portal (IRP), which returns an Invoice Reference Number (IRN) and a signed QR code. The turnover threshold has been lowered in stages since 2020 and has applied to businesses with aggregate annual turnover above âč5 crore since 1 August 2023. Some sectors are exempt. An invoice that should have been registered but wasnât is not treated as a valid tax invoice.
Mexico (CFDI)
Mexico has one of the most mature systems. Practically all invoices must be issued as CFDI (Comprobante Fiscal Digital por Internet) XML files, validated and stamped by an authorised certification provider (PAC) on behalf of the tax authority (SAT). CFDI 4.0 has been mandatory since 1 April 2023. Each stamped invoice receives a unique UUID (folio fiscal), and payments received after invoicing are documented with a payment complement.
Taiwan (e-GUI)
Taiwan uses Government Uniform Invoices (GUI) â numbered invoices whose number ranges are allocated by the tax authority for each two-month period. Electronic GUIs (e-GUIs) are issued and uploaded to the Ministry of Financeâs e-invoice platform within short deadlines (for example, within 48 hours for B2C e-GUIs). Consumers can store them on a âcarrierâ (such as a mobile barcode) and they are automatically entered into Taiwanâs well-known invoice lottery. Foreign providers of electronic services registered in Taiwan generally issue cloud e-GUIs to consumers.
Other notable systems
- Brazil, Chile, Colombia, Peru and other Latin American countries run long-established clearance systems.
- Saudi Arabia has phased in e-invoicing (FATOORA) since December 2021, with integration waves by business size.
- Singapore, Australia and New Zealand promote Peppol-based e-invoicing, mainly for government suppliers so far.
- Japanâs Qualified Invoice System (since October 2023) sets invoice requirements for consumption-tax credits but does not mandate structured e-invoices.
- Spain has legislated a B2B e-invoicing obligation with implementation in phases; check the latest timeline.
What this means for small businesses
- Find out if a mandate applies to you. It typically depends on where youâre established, where your customer is, whether the sale is B2B, B2G or B2C, and sometimes your turnover.
- Check your receiving obligations. In Germany and Poland, for instance, you must be able to receive e-invoices before youâre required to issue them.
- Choose a compliant tool or provider for in-scope invoices â accounting software, a Peppol access point, or a certified platform, depending on the country.
- Keep your data clean. E-invoices are validated automatically; wrong VAT numbers or missing fields cause rejections.
- Keep PDFs for what theyâre good for: B2C sales, countries without mandates, many international B2B invoices, quotes, receipts and proformas.
Where BillKit fits
BillKit creates professional PDF invoices, quotes and receipts in your browser. PDFs remain valid and widely used where structured e-invoicing isnât required â for example, many cross-border B2B invoices, most B2C invoices, and countries without mandates. Where a mandate applies to a transaction (such as domestic B2B invoices in Italy or Poland), youâll need to issue that invoice through a compliant e-invoicing system. For the general content of an invoice, see what to include on an invoice and our country invoice templates.
Reminder: e-invoicing timelines and requirements change often, and this overview simplifies them. It is not legal or tax advice â confirm current obligations with official sources or a tax adviser.