What is PDF/A-3 and how is it used in hybrid e-invoicing?
PDF/A-3 is an ISO 19005-3 standard for PDF archiving that allows embedding machine-readable file attachments within a PDF document. In hybrid e-invoicing (particularly Factur-X and ZUGFeRD), a structured XML invoice file is embedded within a human-readable PDF/A-3, creating a single file that satisfies both human readability requirements and machine-processing requirements.
How does the PDF/A-3 hybrid invoice format work?
In a hybrid invoice: (1) The outer shell is a valid PDF/A-3 compliant PDF that can be read, printed, and archived by any PDF reader; (2) An XML file (using Factur-X/EN 16931 or ZUGFeRD schema) is embedded as an attachment with a specific relationship tag; (3) Receiving systems that support structured e-invoicing parse the embedded XML; (4) Receiving systems without e-invoice capability render the PDF. The XMP metadata in the PDF indicates which profile level applies.
Frequently Asked Questions
- Is a PDF/A-3 Factur-X invoice legally binding in France?
- Yes. A Factur-X PDF/A-3 invoice with an embedded EN 16931-compliant XML is legally valid for VAT purposes in France. French tax authority guidance confirms that hybrid invoices meeting the Factur-X specification satisfy the invoice integrity and authenticity requirements under CGI Article 289. From 2026, Factur-X will be an approved format for B2B e-invoicing compliance under the French mandate.
- What is the difference between PDF/A-1, PDF/A-2, and PDF/A-3 for invoicing?
- PDF/A-1 (ISO 19005-1) prohibits embedded file attachments, so cannot be used for hybrid invoicing. PDF/A-2 (ISO 19005-2) permits embedded files only in PDF/A format. PDF/A-3 (ISO 19005-3) permits embedded files of any type, including XML, enabling the attachment of structured invoice data. For e-invoicing purposes, PDF/A-3 is required; PDF/A-1 and PDF/A-2 cannot carry the structured XML attachment needed for hybrid formats.