Start with the recipient
Both formats can carry structured invoice data, but recipient requirements determine the useful choice. XRechnung commonly appears in public-sector workflows. ZUGFeRD/Factur-X offers a readable PDF with embedded CII XML. Confirm the accepted profile and delivery channel.
Use the supported profile
FakturFokus generates XRechnung UBL and Factur-X EN16931 hybrid PDFs. It can inspect XRechnung CII but does not generate that syntax. Other hybrid profiles can be partial or unsupported. Do not assume every file named invoice.pdf has the same conformance.
Check current obligations separately
German B2B receiving requirements started in 2025. Issuance transitions differ by turnover, with exceptions including Kleinunternehmer. Use the official tax authority guidance for the actual dates and scope. File-format validation does not decide tax treatment.