Creating ZUGFeRD-Compliant PDF Documents

Introduction

ZUGFeRD (Zentraler User Guide des Forums elektronische Rechnung Deutschland) is a German standard for electronic invoicing that combines PDF documents with embedded XML data. It allows for both human-readable PDF invoices and machine-readable structured data in a single file, enabling automated processing while maintaining traditional PDF workflow compatibility.

A ZUGFeRD-compliant PDF document must meet the following requirements:

Be PDF/A-3b compliant
Include the invoice data as an XML attachment
Contain specific XMP metadata

WARNING

ZUGFeRD comes in different versions with varying requirements. This documentation covers ZUGFeRD 2.1, which is based on the UN/CEFACT Cross Industry Invoice (CII) standard.

When implementing ZUGFeRD support, ensure you're using the correct version for your needs and that all components (XML schema, metadata, and PDF/A version) align with that version.

QUALITY ASSURANCE

The validation process can vary across different tools, often producing different results.

At QuestPDF, as part of our CI/CD pipeline, we use automated document validation with veraPDF (to verify PDF/A-3b compliance) and the Mustang Project (to verify ZUGFeRD compliance). Both tools are open-source and free to use.

In addition, we periodically perform manual validation using the Adobe Acrobat Pro Preflight tool to further ensure compliance.

Document Creation

Here's a complete example showing how to create a ZUGFeRD-compliant PDF document:

csharp

Document
    .Create(document =>
    {
        document.Page(page =>
        {
            page.Content().Text("Your invoice content");
        });
    })
    .WithMetadata(new DocumentMetadata
    {
        Title = "Conformance Test: ZUGFeRD",
        Author = "SampleCompany",
        Subject = "ZUGFeRD Test Document",
        Language = "en-US"
    })
    .WithSettings(new DocumentSettings { PdfA = true }) // PDF/A-3b
    .GeneratePdf("invoice-bbb.pdf");

DocumentOperation
    .LoadFile("invoice.pdf")
    .AddAttachment(new DocumentOperation.DocumentAttachment
    {
        Key = "factur-zugferd",
        FilePath = "resource-factur-x.xml",
        AttachmentName = "factur-x.xml",
        MimeType = "text/xml",
        Description = "Factur-X Invoice",
        Relationship = DocumentOperation.DocumentAttachmentRelationship.Source,
        CreationDate = DateTime.UtcNow,
        ModificationDate = DateTime.UtcNow
    })
    .ExtendMetadata(File.ReadAllText("resource-zugferd-metadata.xml"))
    .Save("zugferd-invoice.pdf");

TIP

Find the full example here: ZUGFeRD Example

Creating ZUGFeRD-Compliant PDF Documents ​

Introduction ​

Document Creation ​

Creating ZUGFeRD-Compliant PDF Documents

Introduction

Document Creation