Embedding fonts in PDF/A: why Arial is often missing and what helps

A common stumbling block with ZUGFeRD: the source PDF comes from an older system and uses Arial or Arial Bold without embedding those fonts. This means the file is already not PDF/A compliant before any conversion even takes place.

> Quick answer: PDF/A requires all fonts to be embedded in the file. Older ERP systems often fail to embed Arial/Arial Bold – the PDF is then not PDF/A compliant, and this cannot be fixed by merely embedding the ZUGFeRD XML. The solution: export PDF/A directly from the system, or use XRechnung.

Why fonts must be embedded

PDF/A is an archival format: it is meant to guarantee that a document still looks identical many years from now. A file that relies on the reader having Arial installed does not meet this requirement – on a system without that font, the display would differ. That is why the font data must be contained within the PDF itself.

How to check it

Adobe Acrobat: File → Properties → the „Fonts“ tab. If the „Embedded“ note is missing, the font is not included.
veraPDF: the open PDF/A validator flags non-embedded fonts as a violation.

Why embedding the XML is not enough

A widespread misconception: „If the ZUGFeRD XML and the PDF/A metadata are in there, the file is PDF/A.“ That is not true. Metadata only marks the intent; the missing fonts stay missing. For genuine compliance, the fonts would have to be embedded and a colour profile added.

The two practical solutions

Produce PDF/A in the source system: many ERP and word-processing systems can output PDF/A directly (with embedded fonts). The ZUGFeRD file generated from it is then compliant.
XRechnung instead of ZUGFeRD: with a pure XRechnung (XML) there is no PDF container, so the font question does not arise at all.

Conclusion

Non-embedded fonts are the most common cause of non-compliant ZUGFeRD PDFs. If you are coming from an older system, it is best to export PDF/A directly – or rely on XRechnung.

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The e-invoice XML at TaxLayer is always EN 16931 and KoSIT validated. Questions about PDF/A compliance? info@landauer.de.

Frequently asked questions

Why must fonts be embedded in PDF/A?

So that the document is displayed identically on any computer and many years from now. If the file relies on a system font like Arial that is not installed everywhere, the display may change – and PDF/A forbids that.

How can I tell whether fonts are missing?

In Adobe Acrobat under File → Properties → Fonts: if a font is not marked as „Embedded“ or „Embedded Subset“, it is missing. A PDF/A validator like veraPDF reports this as well.

Does embedding the ZUGFeRD XML make my PDF compliant?

No. Embedding the XML and metadata does not make a PDF PDF/A compliant after the fact. Missing fonts stay missing. Details in PDF/A-3B and veraPDF.

How do I get a PDF/A compliant invoice?

The best approach is to export the invoice directly as PDF/A (with embedded fonts) from your ERP or invoicing system. Alternatively, use a pure XRechnung, where the PDF container is not needed at all.