E-Invoicing Guide 2026: Mandates, Peppol and Structured Formats
E-invoicing explained: what counts as an electronic invoice, Peppol and EN 16931 formats, clearance models and a 2026 overview of mandates around the world.
Quick answer: E-invoicing is the exchange of invoices as structured, machine-readable data, such as UBL or CII XML files, rather than as PDFs or paper. A growing number of countries now require it for business-to-business or business-to-government sales, often through a government platform or a network such as Peppol. A PDF emailed to a client is an electronic document, but under most mandates it is not an "e-invoice".
This e-invoicing guide explains what counts as an e-invoice, the main formats and networks, the different mandate models, and where major mandates stood as of October 2026. Where no mandate applies, a clear PDF from our free invoice generator remains a perfectly good invoice; where one does, you will need compliant software.
Important: This is general information, not tax or legal advice. E-invoicing rollout dates, thresholds and technical specifications change frequently, and several have been postponed in the past. Check the official tax authority guidance in each country where you are registered, or ask a qualified adviser, before planning around any date in this article.
What counts as an e-invoice
Under the EU definition, an electronic invoice is one issued, transmitted and received in a structured electronic format that allows automatic and electronic processing. In practice that means a data file whose fields (seller, buyer, tax IDs, line items, tax amounts, totals) are tagged so software can read them without a human retyping anything.
| Document | Structured data? | Typically meets an e-invoicing mandate? |
|---|---|---|
| Paper invoice | No | No |
| PDF invoice sent by email | No | No |
| Scanned invoice processed by OCR | No (extracted later) | No |
| Hybrid PDF with embedded XML (e.g. Factur-X / ZUGFeRD) | Yes, in the XML part | Often, depending on the country and profile |
| UBL or CII XML file exchanged via Peppol or a tax platform | Yes | Yes, if it follows the local specification |
The content requirements of a tax invoice do not disappear with e-invoicing; they are simply expressed as data fields. Our tax invoice guide covers those core fields.
Formats and standards you will hear about
- EN 16931: the European standard that defines the core semantic data model of an electronic invoice. It can be expressed in two syntaxes, UBL and UN/CEFACT CII.
- UBL (Universal Business Language): an XML standard widely used for invoices, including on Peppol.
- CII (Cross Industry Invoice): the UN/CEFACT XML syntax, used in formats such as Factur-X and ZUGFeRD.
- Factur-X / ZUGFeRD: hybrid formats, mainly used in France and Germany, that embed CII XML inside a PDF so humans and machines can both read the invoice.
- XRechnung: Germany's national specification based on EN 16931, originally for invoices to the public sector.
- Peppol BIS Billing: the Peppol specification for invoices and credit notes, built on EN 16931.
- Country-specific formats: for example FatturaPA in Italy, CFDI in Mexico and the formats used by India's Invoice Registration Portal.
How Peppol works
Peppol is a network and set of specifications for exchanging business documents. It uses a "four-corner" model:
- The supplier (corner 1) creates the invoice in its software.
- The supplier's access point (corner 2), a certified service provider, sends it across the network.
- The buyer's access point (corner 3) receives it.
- The buyer (corner 4) gets the invoice straight into its accounting system.
Because every access point speaks the same standard, a supplier only needs one connection to reach any registered buyer. Some countries add a "fifth corner" in which invoice data is also reported to the tax authority. Peppol is used in many European countries and also in countries such as Australia, New Zealand, Singapore, Japan and Malaysia, for public-sector or voluntary B2B exchange in many cases.
The main e-invoicing models
| Model | How it works | Examples |
|---|---|---|
| Post-audit / interoperability | Parties exchange structured invoices directly or via a network; tax authority checks later | Peppol-based mandates such as Belgium |
| Clearance | Invoice is validated by a tax platform before or as it reaches the buyer | Italy (SdI), Mexico (CFDI), Brazil (NF-e) |
| Real-time or periodic reporting | Invoice data is reported to the authority soon after issue | Hungary, Spain's SII for larger businesses |
| Hybrid / decentralized CTC | Network exchange plus reporting to the authority | France's planned model, the EU's ViDA reporting |
E-invoicing mandates: where things stood in 2026
The list below reflects mandates as announced at the time of writing. Dates have moved before, so treat each as a prompt to check the official source.
- Italy: mandatory B2B and B2C e-invoicing through the SdI platform since 2019.
- Germany: all domestic businesses must be able to receive e-invoices since 1 January 2025. Issuing becomes mandatory in phases, with businesses above €800,000 turnover from 2027 and all businesses from 2028.
- Belgium: structured B2B e-invoicing, generally via Peppol, mandatory from 1 January 2026.
- France: a phased rollout through certified platforms, with receiving for all businesses and issuing for larger companies scheduled from September 2026, and issuing for small and micro businesses from September 2027.
- Poland: the national KSeF system became mandatory in stages during 2026, starting with the largest taxpayers.
- European Union: the VAT in the Digital Age (ViDA) package, adopted in 2025, makes e-invoicing the default for intra-EU B2B supplies with digital reporting from July 2030, and lets member states impose domestic mandates without special approval.
- United Kingdom: the government has announced mandatory B2B and B2G e-invoicing from April 2029, with details still being developed.
- Saudi Arabia: the FATOORA program began in December 2021, with integration with the authority's platform rolled out to taxpayers in waves.
- United Arab Emirates: a phased e-invoicing program using accredited service providers, with the first phases starting in 2026 to 2027 for larger businesses. See UAE VAT invoice requirements for current tax invoice fields.
- India: GST e-invoicing with an Invoice Reference Number (IRN) applies to businesses above a turnover threshold, which has been lowered several times. Our GST invoice guide covers related fields.
- Pakistan: certain retailers must issue invoices through systems integrated with the FBR, and electronic invoicing for sales-tax registered persons has been extended in phases. See sales tax invoices in Pakistan.
- Malaysia: MyInvois e-invoicing phased in from 2024 by turnover band.
- Latin America: Mexico, Brazil, Chile and others have used clearance e-invoicing for many years.
- United States: no general federal B2B mandate; adoption is voluntary, with some public-sector requirements.
How to prepare your business
Step 1: Map where you are registered
Mandates follow your tax registrations and your customers' locations. List every country where you are VAT- or GST-registered and every public-sector customer you bill.
Step 2: Clean your master data
Structured invoices are rejected automatically when data is wrong. Check customer legal names, addresses and tax numbers; our guide to the tax ID on an invoice covers the common identifiers.
Step 3: Choose software or a service provider
To issue mandated e-invoices you typically need accounting or invoicing software that outputs the required format, plus a Peppol access point or a connection to the national platform. Our comparison of an invoice generator vs accounting software helps you decide when to move up.
Step 4: Plan for receiving as well as sending
Several mandates require businesses to receive e-invoices before issuing becomes compulsory, so your accounts payable process needs to change too.
Step 5: Review archiving
The structured file is usually the legal original, so you must keep it, not just a PDF view of it. See how long to keep invoices.
Where PDF invoices still fit
For freelancers and small businesses selling domestically in countries without a mandate, or to consumers, or to clients abroad who accept PDFs, a well-structured PDF remains normal practice. Clear field labels and consistent tax IDs also make your PDFs easier for automated capture tools. Country presets such as the UAE invoice generator and Pakistan invoice generator set local tax ID labels, but they produce PDF invoices, not mandated structured e-invoices.
Country rules differ a lot. For the networks and mandates in detail, see what Peppol is and how it works, the ZATCA e-invoicing guide for Saudi Arabia, the France e-invoicing reform and XRechnung vs ZUGFeRD in Germany.
Create a clear invoice now
If no e-invoicing mandate applies to your sales yet, open the invoice generator and download a clean PDF in minutes. A tidy, structured layout such as the Slate invoice template keeps every field easy to find, and you can browse all invoice templates to match your brand. Check the latest mandate dates with your tax authority before each new year.
Frequently asked questions
Is a PDF invoice an e-invoice?
Under most e-invoicing mandates, no. A mandated e-invoice is a structured, machine-readable file such as UBL or CII XML that software can process automatically. A PDF can still be a valid invoice where no mandate applies, and hybrid formats combine a PDF with embedded XML.
What is Peppol?
Peppol is an international network and set of specifications for exchanging electronic business documents, including invoices. Businesses connect through certified access points, so a sender can reach any registered receiver regardless of which provider each uses.
Is e-invoicing mandatory in the US?
As of 2026 there is no general federal B2B e-invoicing mandate in the US. Some public-sector buyers require electronic submission, and there is a voluntary industry framework, but businesses can generally still use PDF invoices.
Does e-invoicing apply to small businesses?
Often yes, eventually. Many mandates start with large businesses and extend to small and micro businesses later, and some require every business to be able to receive e-invoices before issuing is compulsory. Check the timetable in each country where you are registered.
What is a clearance model?
In a clearance model, the invoice is sent to or validated by a tax authority platform before or as it reaches the buyer. Italy, Mexico and Brazil are long-standing examples.
What is the difference between e-invoicing and EDI?
EDI (electronic data interchange) is an older way for trading partners to exchange business documents in agreed formats, often through private connections set up one partner at a time. Modern e-invoicing uses standardized formats such as EN 16931, UBL or CII and open networks like Peppol, so one connection can reach many buyers. Both are structured data, but mandates specify particular formats and channels.
How do I get a Peppol ID?
You get a Peppol ID by registering with a certified Peppol access point provider, often through your accounting or invoicing software. The provider registers your business identifier, such as a VAT or company number, in the network directory so others can find you and send you e-invoices. Costs and setup vary by provider, and some accounting packages include Peppol access in their plans.
What happens if I send a PDF invoice where e-invoicing is mandatory?
The invoice may not count as a valid invoice for tax purposes. Depending on the country, that can mean penalties for you, a buyer who won't pay until they receive a compliant e-invoice, or a customer who cannot deduct the VAT. Some countries allow transition periods or exceptions, so check the rules and timelines in each country where you're registered.
Can a free invoice generator create a legally valid e-invoice?
Usually not. Most free generators, including ours, create PDF invoices, which are fine where no mandate applies but are not the structured XML files or platform submissions that mandates require. They also don't add clearance stamps, IRNs or tax authority QR codes. Where e-invoicing is compulsory, use software that supports the required format or a certified service provider.
Are there free e-invoicing options for small businesses?
Some governments offer free basic tools. Malaysia's MyInvois Portal lets businesses submit e-invoices online, and Italy's tax agency provides free tools for creating and sending invoices through its exchange system. Elsewhere, low-cost accounting software often includes e-invoicing. Check your tax authority's website first, because a free official portal may be enough if you send only a few invoices.
Invoice Creator Editorial Team
Guides on invoicing, cash flow and small-business finance from Invoice Creator, operated by Next Software Development Company. Content is reviewed for accuracy against the fields our own invoice generator produces.
Try the invoice generator