ZUGFeRD and XRechnung Invoices

Updated on Oct 29, 2026

This article explains how to embed ZUGFeRD and XRechnung invoices in PDF documents with Telerik PdfProcessing.

The feature is available starting with Q4 2025.

ZUGFeRD (acronym for Zentraler User Guide des Forums elektronische Rechnung Deutschland) is a specification for the electronic invoice format of the same name. RadPdfProcessing supports embedding ZUGFeRD invoices, including the XRechnung profile for German public-sector electronic invoicing compliance.

Creating an Embedded Electronic (ZUGFeRD) Invoice

Adding a ZUGFeRD Invoice

C#

RadFixedDocument document = new RadFixedDocument();
using (RadFixedDocumentEditor editor = new RadFixedDocumentEditor(document))
{
    editor.CharacterProperties.TrySetFont(new FontFamily("Calibri"));
    editor.InsertRun("PDF/A-3B Compliant Invoice");
}

;
byte[] bytes = File.ReadAllBytes(@"zugferd-invoice.xml");
document.EmbeddedFiles.AddZugferdInvoice(bytes);

PdfFormatProvider provider = new PdfFormatProvider();
PdfExportSettings settings = new PdfExportSettings();
settings.ComplianceLevel = PdfComplianceLevel.PdfA3B;
provider.ExportSettings = settings;
using (Stream output = File.OpenWrite("exportedInvoice.pdf"))
{
    provider.Export(document, output, TimeSpan.FromSeconds(10));
}

Only a single XML invoice attachment is allowed according to the ZUGFeRD standard.

To comply with the PDF/A-3B standard, all the fonts in the documents must be embedded. Avoid using Standard Fonts because they are not embedded in the document. In .NET Standard/.NET (Target OS: None) environments, fonts beyond the 14 standard ones require a FontsProvider implementation to be resolved correctly.

Removing a ZUGFeRD Invoice

C#

if (document.EmbeddedFiles.ContainsZugferdInvoice)
{
    document.EmbeddedFiles.RemoveZugferdInvoice();
}

Specifying ZUGFeRD Conformance Levels

Starting with Q4 2025, RadPdfProcessing supports specifying the ZUGFeRD (Factur-X) conformance level when exporting PDF invoices. Higher levels generally include all requirements of the lower levels and add more structured data to support automated processing and validation scenarios.

RadPdfProcessing allows you to set the ZugferdConformanceLevel when embedding the invoice. The available options are:

Level	Description
Minimum	The minimal profile providing only the essential data needed for a compliant e-invoice. Suitable for simple use cases with limited automation.
Basic	The basic profile providing core structured data for improved interoperability and basic automated processing between trading partners. This is the default value.
Comfort	The comfort profile with richer structured content, typically aligned with common business requirements to enable advanced automation.
Extended	The most comprehensive profile including extended data elements to cover advanced or industry-specific scenarios beyond the comfort profile.
XRechnung	The German CIUS (Core Invoice Usage Specification) reference profile based on EN 16931. Used for public-sector electronic invoicing in Germany. Exports with XRECHNUNG conformance metadata and embeds the invoice XML as xrechnung.xml.

C#

RadFixedDocument fixedDocument = new RadFixedDocument();
fixedDocument.EmbeddedFiles.AddZugferdInvoice(File.ReadAllBytes(@"zugferd-invoice.xml"), Telerik.Documents.Fixed.Model.EmbeddedFiles.ZugferdConformanceLevel.Comfort);

XRechnung Profile

XRechnung is the German electronic invoicing standard mandated for public-sector invoicing. ZUGFeRD 2.1.1 defines an XRECHNUNG profile that enables XRechnung-compliant invoice data to be embedded in a PDF/A-3 document.

When you set the conformance level to XRechnung, RadPdfProcessing automatically:

• Sets the conformance level metadata to XRECHNUNG in the XMP metadata.
• Embeds the invoice XML with the filename xrechnung.xml instead of the default factur-x.xml.

C#

RadFixedDocument document = new RadFixedDocument();
byte[] invoiceXml = File.ReadAllBytes("xrechnung-invoice.xml");

document.EmbeddedFiles.AddZugferdInvoice(invoiceXml, ZugferdConformanceLevel.XRechnung);

PdfFormatProvider provider = new PdfFormatProvider();
// Export as PDF/A-3B for ZUGFeRD compliance.
provider.ExportSettings.ComplianceLevel = PdfComplianceLevel.PdfA3B;
File.WriteAllBytes("output.pdf", provider.Export(document, TimeSpan.FromSeconds(10)));

When using the XRechnung conformance level, the embedded filename is fixed to xrechnung.xml. For all other conformance levels, the filename is factur-x.xml.

Validating Documents

RadPdfProcessing follows the business-rule validation for ZUGFeRD and Factur-X XML published by the European Committee for Standardization: Open-source E-invoice Validator.

See Also

• Embedded File Streams