Electronic invoicing is becoming a standard requirement for businesses, governments, and tax authorities worldwide. However, sending an invoice electronically does not automatically make it a compliant e-invoice. A true electronic invoice must follow a structured or hybrid e-invoice format that enables accounting, ERP, and tax systems to process the invoice data automatically.
There are many types of e-invoice formats, including XML, UBL, EDIFACT, ZUGFeRD, XRechnung, Peppol BIS, and country-specific standards. Understanding these formats is essential for maintaining tax compliance, reducing manual data entry, and supporting cross-border trade.
This guide explains the most widely used e-invoicing formats, how they work, and how to select the right option for your business.
What Is an Electronic Invoice?
An electronic invoice is an invoice that is created, transmitted, received, and processed in a digital format.
Unlike a scanned document or a standard PDF invoice, a structured e-invoice contains data in predefined fields. These fields may include:
- Supplier and buyer information
- Invoice number and issue date
- Tax identification numbers
- Product or service descriptions
- Quantities and unit prices
- VAT rates and tax amounts
- Payment terms
- Bank account details
- Invoice totals
Because the information follows a defined structure, accounting and tax systems can read it without requiring employees to enter the data manually.
A PDF sent by email may be an electronic document, but it is generally not considered a fully structured e-invoice unless it contains embedded machine-readable data.
Why Are e-Invoicing Formats Important?
E-invoicing formats determine how invoice information is organised and exchanged between businesses, public authorities, accounting platforms, and tax administrations.
Using the correct e-invoicing format helps businesses:
- Automate invoice processing
- Reduce manual data-entry errors
- Improve payment processing
- Prevent duplicate invoices
- Support real-time or near-real-time tax reporting
- Meet local tax compliance requirements
- Exchange invoices across different accounting systems
- Simplify cross-border transactions
The correct format is particularly important for businesses operating in multiple countries. An invoice accepted in one jurisdiction may not meet the technical or legal requirements of another.
For example, e-invoicing in europe commonly follows the EN 16931 semantic data model, but individual countries may implement it through standards such as XRechnung, Factur-X, or national adaptations of Peppol BIS.
Pure Structured e-Invoicing Formats
Pure structured formats contain machine-readable data without relying on a visual invoice document. They are mainly designed for automated system-to-system processing.
XML (eXtensible Markup Language)
XML is one of the most widely used technologies for electronic invoicing. It stores invoice data using labelled elements that describe each piece of information.
For example, an XML invoice may contain separate tags for the invoice number, issue date, supplier name, currency, tax amount, and payable total.
XML is flexible and can be adapted to different industries and tax systems. Many national e-invoicing formats, including XRechnung, FatturaPA, and Facturae, are based on XML.
However, generic XML is not automatically a compliant invoice format. Businesses must follow a specific XML schema and validation rules defined by the relevant standard or tax authority.
UBL (Universal Business Language)
UBL is an open standard developed by OASIS for common business documents such as invoices, purchase orders, credit notes, and dispatch advice.
UBL uses XML but provides predefined structures and business terms. This makes it easier for different accounting and procurement systems to exchange documents consistently.
UBL is widely used in international procurement and forms the technical basis of many Peppol invoice implementations. It is one of the most important e-invoicing formats in Europe and is also used in other regions.
JSON (JavaScript Object Notation)
JSON is a lightweight data format commonly used by web applications and APIs.
Invoice data in JSON can be transmitted quickly between cloud accounting platforms, e-commerce systems, and payment applications. It is easier for many software developers to read and implement than traditional XML.
However, JSON is usually a technical data-exchange method rather than a legally recognised national e-invoice standard. Businesses must confirm whether the receiving platform or tax authority officially supports the relevant JSON structure.
EDIFACT (Electronic Data Interchange)
UN/EDIFACT is an established electronic data interchange standard used by large enterprises, manufacturers, logistics companies, and retailers.
Its INVOIC message is specifically designed for invoices. EDIFACT can support high-volume, automated transactions between established trading partners.
Although it remains reliable, its implementation can be more complex and expensive than modern XML- or API-based alternatives. It is therefore most common in mature EDI environments and supply chains.
Hybrid e-Invoice Formats
Hybrid formats combine a human-readable invoice with structured data that software can process automatically.
ZUGFeRD / Factur-X
ZUGFeRD and Factur-X are hybrid e-invoice formats that combine a PDF/A-3 document with an embedded XML file.
The PDF allows a person to open and read the invoice normally, while the XML component enables accounting software to extract and process the invoice data automatically.
ZUGFeRD is the commonly used name in Germany, while Factur-X is used primarily in France. The standards are technically aligned and designed to support European e-invoicing requirements.
This hybrid approach is particularly useful for small and medium-sized businesses because the recipient can still view the invoice as a familiar PDF even when their accounting system does not process the embedded data automatically.
Network and Country-Specific Standards
Some standards define not only the invoice structure but also business rules, validation requirements, or delivery methods.
Peppol BIS
Peppol BIS Billing is a business specification for exchanging electronic invoices through the Peppol network.
It is based on the European EN 16931 standard and commonly uses UBL syntax. Peppol enables businesses and public organisations to exchange structured invoices through approved Access Points.
Peppol is widely used for B2G and B2B e-invoicing, particularly in Europe, but its adoption has also expanded into other regions.
XRechnung
XRechnung is Germany’s structured electronic invoice standard, originally developed for invoicing public-sector customers.
It implements the European EN 16931 requirements through specific German business and validation rules. XRechnung invoices are machine-readable XML documents and commonly use UBL or UN/CEFACT syntax.
Unlike ZUGFeRD, a standard XRechnung invoice does not require a human-readable PDF component.
FatturaPA
FatturaPA is Italy’s XML-based electronic invoice format.
Invoices are generally submitted through the government’s Sistema di Interscambio, commonly known as SdI. The system validates the document and routes it to the appropriate recipient.
The format contains detailed information about the supplier, buyer, tax treatment, invoice lines, payment conditions, and document type.
Facturae
Facturae is Spain’s structured electronic invoicing format, particularly associated with invoices submitted to public administrations.
It is based on XML and can include an electronic signature. The standard defines required invoice fields, tax information, payment details, and information about the issuing and receiving parties.
Which e-Invoice Formats Are Commonly Used?
The most common types of e-invoice formats include:
- UBL for international procurement and Peppol transactions
- XML for national tax and reporting systems
- ZUGFeRD or Factur-X for hybrid PDF and XML invoicing
- XRechnung for structured invoicing in Germany
- FatturaPA for invoicing through Italy’s SdI platform
- Facturae for Spanish public-sector invoicing
- EDIFACT for established enterprise supply chains
The most suitable format depends on the countries involved, the recipient’s requirements, transaction volume, and the capabilities of the accounting software.
How to Choose the Right e-Invoicing Format for Your Business
Start by identifying where your customers are located and whether they are businesses, consumers, or government organisations.
You should also evaluate:
- National tax authority requirements
- Customer or public-sector procurement rules
- ERP and accounting software compatibility
- Whether structured data is mandatory
- Whether a visible PDF is required
- Peppol network availability
- Digital signature or archiving requirements
- Cross-border interoperability
Businesses operating in multiple jurisdictions should use an e-invoicing provider that can convert invoice data into different national formats and update validation rules when regulations change.
FAQs About e-Invoicing Formats
Do e-invoice formats vary by country?
Yes. Countries may require different invoice schemas, tax fields, transmission platforms, signatures, and validation rules. Businesses should always check the requirements of the jurisdiction where the invoice is issued or received.
Are ZUGFeRD and Factur-X the same?
They are technically aligned hybrid formats combining a PDF/A-3 invoice with embedded XML data. ZUGFeRD is the name commonly used in Germany, while Factur-X is commonly used in France.
Can I use a PDF as an e-invoice format?
A basic PDF is generally considered an unstructured electronic document rather than a structured e-invoice. A hybrid PDF such as ZUGFeRD or Factur-X may qualify because it includes embedded machine-readable XML data.
Which e-invoicing format is best for B2B?
UBL, Peppol BIS, ZUGFeRD, Factur-X, and country-specific XML formats are commonly used for B2B transactions. The best option depends on national legislation, customer requirements, and system compatibility.
Which e-invoicing format is best for B2C?
For B2C transactions, a readable PDF or customer-friendly visual invoice may still be useful. However, businesses must also meet any mandatory tax reporting or clearance requirements. In some countries, the invoice must be submitted to a government platform even when the customer receives a PDF copy.