Invoice Formats

thelawin.dev supports 9 different invoice formats to comply with various national and international e-invoicing regulations.

Overview

Format	Output	Region	Use Case
AUTO	Varies	Auto-detect	Let the API choose
ZUGFERD	PDF + CII XML	Germany	German B2B invoices
FACTURX	PDF + CII XML	France	French B2B/B2G invoices
XRECHNUNG	PDF + UBL XML	Germany	German B2G (mandatory)
UBL	XML only	Global	OASIS standard
CII	XML only	Global	UN/CEFACT standard
PEPPOL	XML only	EU/UK/AU/SG/NZ	Cross-border network
FATTURAPA	XML only	Italy	Italian SDI (mandatory)
PDF	PDF only	Any	Plain invoices

AUTO

Auto-detection - Let the API choose the best format based on your invoice data.

How it works

The API analyzes your invoice data and selects the appropriate format:

Italy buyer + codice_fiscale → FatturaPA
Germany buyer + leitweg_id → XRechnung
Peppol IDs present → Peppol
France seller → Factur-X
Germany seller → ZUGFeRD
Otherwise → ZUGFeRD (default)

Example

json

{
  "format": "auto",
  "invoice": {
    "seller": { "country": "DE" },
    "buyer": { "country": "IT", "codice_fiscale": "12345678901" }
  }
}

→ Result: FatturaPA XML (because Italian buyer has codice_fiscale)

ZUGFERD

PDF/A-3 + CII XML - German standard for electronic invoices.

Specifications

Standard: ZUGFeRD 2.3
Profile: EN 16931 (recommended)
Output: Visual PDF with embedded XML
Legal basis: § 14 UStG, EU Directive 2014/55/EU

Required Fields

seller.vat_id (for EN16931 profile)
seller.name, seller.country
buyer.name, buyer.country
items[].description, items[].quantity, items[].unit_price

Example

json

{
  "format": "zugferd",
  "profile": "en16931",
  "invoice": {
    "number": "RE-2026-001",
    "date": "2026-01-07",
    "seller": {
      "name": "Acme GmbH",
      "vat_id": "DE123456789",
      "country": "DE"
    },
    "buyer": {
      "name": "Customer AG",
      "country": "DE"
    },
    "items": [{
      "description": "Consulting",
      "quantity": 8,
      "unit": "HUR",
      "unit_price": 150,
      "vat_rate": 19
    }]
  }
}

Use Cases

German B2B: Recommended for all German business-to-business invoices
EU Cross-border: Accepted across EU
Accounting Software: Automatically processable by DATEV, SAP, etc.

FACTURX

PDF/A-3 + CII XML - French standard (identical to ZUGFeRD).

Specifications

Standard: Factur-X 1.0 (= ZUGFeRD 2.3)
Profile: EN 16931
Output: Visual PDF with embedded XML
Legal basis: Ordonnance 2021-1190, EU Directive 2014/55/EU

Required Fields

Same as ZUGFeRD (see above)

Example

json

{
  "format": "facturx",
  "profile": "en16931",
  "locale": "fr"
}

Use Cases

French B2B: Recommended for French business invoices
Chorus Pro: Required for French public sector (B2G)
EU Cross-border: Accepted across EU

Deadlines

B2G: Mandatory since 2020
Large B2B: Mandatory from 2026-09-01
SME B2B: Mandatory from 2027-09-01

XRECHNUNG

PDF/A-3 + UBL XML - German B2G standard (mandatory for public sector).

Specifications

Standard: XRechnung 3.0 (UBL 2.1 based)
Profile: EN 16931
Output: Visual PDF with embedded UBL XML
Legal basis: E-Rechnungs-Verordnung (ERechV), § 27 Abs. 38 UStG

Required Fields

All ZUGFeRD fields PLUS:

invoice.leitweg_id - Routing ID for German authorities
invoice.buyer_reference - Purchase order number (recommended)

Leitweg-ID Format

<Behördenkennung>-<Rechnungsempfänger>-<Leitweg>
Example: 04011000-12345-67

Example

json

{
  "format": "xrechnung",
  "invoice": {
    "leitweg_id": "04011000-12345-67",
    "buyer_reference": "PO-2026-123",
    "seller": {
      "name": "Software GmbH",
      "vat_id": "DE987654321"
    },
    "buyer": {
      "name": "Bundesbehörde"
    }
  }
}

Use Cases

German B2G: Mandatory for all invoices to German public sector since 2020-11-27
Federal Authorities: Required routing via Leitweg-ID
B2B: Optional (ZUGFeRD is more common)

UBL

XML only - OASIS Universal Business Language standard.

Specifications

Standard: UBL 2.1 Invoice
Profile: EN 16931
Output: XML file (no PDF)
Legal basis: OASIS UBL 2.1 Standard

Required Fields

Same as ZUGFeRD

Example

json

{
  "format": "ubl",
  "invoice": {
    "number": "UBL-001",
    "date": "2026-01-07",
    "seller": { "name": "Company Ltd" },
    "buyer": { "name": "Customer Inc" },
    "items": [{
      "description": "Services",
      "quantity": 1,
      "unit_price": 1000
    }]
  }
}

Use Cases

ERP Integration: Machine-to-machine without visual PDF
Base Format: Foundation for XRechnung and Peppol
Custom Processing: When you generate PDFs yourself

CII

XML only - UN/CEFACT Cross-Industry Invoice standard.

Specifications

Standard: UN/CEFACT CII D16B
Profile: EN 16931
Output: XML file (no PDF)

Required Fields

Same as ZUGFeRD

Example

json

{
  "format": "cii",
  "invoice": {
    "number": "CII-001",
    "date": "2026-01-07"
  }
}

Use Cases

Raw XML: Base format for ZUGFeRD/Factur-X
System Integration: When embedding in existing PDF workflow
Custom Workflows: Full control over PDF generation

PEPPOL

XML only - Pan-European Public Procurement Online network.

Specifications

Standard: Peppol BIS Billing 3.0 (UBL-based)
Profile: EN 16931
Output: XML file (no PDF)
Network: Peppol eDelivery Network

Required Fields

All UBL fields PLUS:

seller.peppol_id - Peppol participant ID
buyer.peppol_id - Peppol participant ID
invoice.buyer_reference - Purchase order reference (mandatory)

Peppol ID Format

<EAS code>:<identifier>
Examples:
- 0088:1234567890123 (GLN)
- 0184:123456789 (DUNS)
- 9956:DE123456789 (German VAT ID)

Example

json

{
  "format": "peppol",
  "invoice": {
    "number": "PEPPOL-001",
    "date": "2026-01-07",
    "buyer_reference": "PO-2026-123",
    "seller": {
      "name": "EU Supplier Ltd",
      "peppol_id": "0088:1234567890123"
    },
    "buyer": {
      "name": "EU Customer GmbH",
      "peppol_id": "0088:9876543210987"
    },
    "items": [{
      "description": "Consulting Services",
      "quantity": 10,
      "unit_price": 100
    }]
  }
}

Use Cases

EU Cross-border: Invoices via Peppol network
International B2G: Required in some EU countries
Automated Routing: Network handles delivery

Supported Countries

EU member states, UK, Australia, Singapore, New Zealand, Switzerland, Norway

Network Registration Required

Both sender and receiver must be registered in the Peppol network with Access Points.

FATTURAPA

XML only - Italian SDI (Sistema di Interscambio) standard.

Specifications

Standard: FatturaPA 1.2.1
Profile: Agenzia delle Entrate schema
Output: XML file (for SDI submission)
Legal basis: Art. 1, comma 3, D.Lgs. 127/2015

Required Fields

All UBL fields PLUS:

invoice.tipo_documento - Document type (TD01, TD04, etc.)
seller.codice_fiscale - Italian tax code (11/16 chars)
buyer.codice_fiscale - Buyer's tax code
buyer.codice_destinatario - SDI recipient code (7 chars) OR buyer.pec

Tipo Documento

TD01 - Invoice
TD04 - Credit note
TD05 - Debit note
TD06 - Fee invoice

Codice Destinatario

7 alphanumeric characters OR
0000000 if using PEC (certified email)

VAT Exemption (natura)

N1 - Excluded pursuant to Art. 15
N2 - Not subject to VAT
N3 - Not taxable
N4 - Exempt
N5 - Margin regime
N6 - Reverse charge
N7 - VAT paid in another EU country

Example

json

{
  "format": "fatturapa",
  "invoice": {
    "number": "IT-2026-001",
    "date": "2026-01-07",
    "tipo_documento": "TD01",
    "seller": {
      "name": "Fornitore Italiano SRL",
      "codice_fiscale": "12345678901"
    },
    "buyer": {
      "name": "Cliente Italiano SPA",
      "codice_fiscale": "98765432109",
      "codice_destinatario": "ABCDEFG"
    },
    "items": [{
      "description": "Servizi di consulenza",
      "quantity": 1,
      "unit_price": 1000,
      "vat_rate": 22,
      "natura": "N4"
    }]
  }
}

Use Cases

Italian B2B/B2G: Mandatory for all Italian invoices since 2019-01-01
SDI Submission: XML submitted to Sistema di Interscambio
Reverse Charge: Use natura codes for tax exemptions

Mandatory in Italy

FatturaPA is legally required for all B2B and B2G invoices in Italy. Penalties apply for non-compliance.

PDF

Plain PDF - Visual invoice without embedded XML.

Specifications

Standard: None (visual only)
Output: PDF file (no structured data)
Legal: Not compliant with EU Directive 2014/55/EU

Example

json

{
  "format": "pdf",
  "template": "minimal",
  "invoice": {
    "number": "PLAIN-001",
    "date": "2026-01-07",
    "seller": { "name": "Company" },
    "buyer": { "name": "Customer" },
    "items": [{
      "description": "Product",
      "quantity": 1,
      "unit_price": 100
    }]
  }
}

Use Cases

B2C Invoices: Consumer invoices (no e-invoice required)
Internal Use: Proforma invoices, quotes
Non-EU: Countries without e-invoice requirements

Not Compliant

Plain PDF is NOT compliant with EN 16931 or national e-invoice regulations. Use only for B2C or internal purposes.

Format Selection Guide

Decision Tree

Is buyer Italian with codice_fiscale?
  → YES: FatturaPA

Is buyer German public sector (Behörde)?
  → YES: XRechnung (leitweg_id required)

Do both parties have Peppol IDs?
  → YES: Peppol

Is buyer French?
  → YES: Factur-X

Is buyer/seller German?
  → YES: ZUGFeRD

Otherwise:
  → ZUGFeRD (international standard)

Recommendations

Scenario	Recommended Format	Alternative
German B2B	ZUGFeRD	XRechnung
German B2G	XRechnung	-
French B2B/B2G	Factur-X	ZUGFeRD
Italian B2B/B2G	FatturaPA	-
EU Cross-border	Peppol	ZUGFeRD
ERP Integration	UBL	CII
B2C	PDF	ZUGFeRD
Unsure	AUTO	ZUGFeRD

Legal Compliance

EU Directive 2014/55/EU

All formats (except PDF) comply with EN 16931, the European standard for electronic invoicing.

National Deadlines

Country	B2G Mandatory	B2B Mandatory	Format
🇩🇪 Germany	2020-11-27	Voluntary	XRechnung (B2G), ZUGFeRD (B2B)
🇫🇷 France	2020-01-01	2026-09-01 (large), 2027-09-01 (SME)	Factur-X
🇮🇹 Italy	2019-01-01	2019-01-01	FatturaPA
🇪🇸 Spain	2020-01-15	Planned 2025	Facturae 3.2
🇦🇹 Austria	2020-01-27	Voluntary	EN 16931

API Usage

Setting Format

json

{
  "format": "zugferd",  // or "facturx", "xrechnung", "ubl", etc.
  "profile": "en16931",
  "invoice": { ... }
}

Auto-Detection

json

{
  "format": "auto",  // API chooses best format
  "invoice": { ... }
}

Format Response

The API returns information about the chosen format:

json

{
  "format": {
    "format_used": "zugferd",
    "profile": "EN16931",
    "version": "2.3",
    "format_reason": "Auto-detected based on seller.country=DE",
    "warnings": []
  }
}

Invoice Formats ​

Overview ​

AUTO ​

How it works ​

Example ​

ZUGFERD ​

Specifications ​

Required Fields ​

Example ​

Use Cases ​

FACTURX ​

Specifications ​

Required Fields ​

Example ​

Use Cases ​

Deadlines ​

XRECHNUNG ​

Specifications ​

Required Fields ​

Leitweg-ID Format ​

Example ​

Use Cases ​

UBL ​

Specifications ​

Required Fields ​

Example ​

Use Cases ​

CII ​

Specifications ​

Required Fields ​

Example ​

Use Cases ​

PEPPOL ​

Specifications ​

Required Fields ​

Peppol ID Format ​

Example ​

Use Cases ​

Supported Countries ​

FATTURAPA ​

Specifications ​

Required Fields ​

Tipo Documento ​

Codice Destinatario ​

VAT Exemption (natura) ​

Example ​

Use Cases ​

PDF ​

Specifications ​

Example ​

Use Cases ​

Format Selection Guide ​

Decision Tree ​

Recommendations ​

Legal Compliance ​

EU Directive 2014/55/EU ​

National Deadlines ​

API Usage ​

Setting Format ​

Auto-Detection ​

Format Response ​

Further Reading ​

Invoice Formats

Overview

AUTO

How it works

Example

ZUGFERD

Specifications

Required Fields

Example

Use Cases

FACTURX

Specifications

Required Fields

Example

Use Cases

Deadlines

XRECHNUNG

Specifications

Required Fields

Leitweg-ID Format

Example

Use Cases

UBL

Specifications

Required Fields

Example

Use Cases

CII

Specifications

Required Fields

Example

Use Cases

PEPPOL

Specifications

Required Fields

Peppol ID Format

Example

Use Cases

Supported Countries

FATTURAPA

Specifications

Required Fields

Tipo Documento

Codice Destinatario

VAT Exemption (natura)

Example

Use Cases

PDF

Specifications

Example

Use Cases

Format Selection Guide

Decision Tree

Recommendations

Legal Compliance

EU Directive 2014/55/EU

National Deadlines

API Usage

Setting Format

Auto-Detection

Format Response

Further Reading