Validation rules
BR-O-02 — EN 16931 rule
The invoice has "not subject to VAT" (O) lines, which forbid a seller VAT identifier (BT-31), the VAT identifier of a seller tax representative (BT-63) and a buyer VAT identifier (BT-48) on the invoice.
- Rule
BR-O-02— official EN 16931 / XRechnung rule- Severity
- error
- Business term
BT-31— Seller VAT identifier- Field in your JSON
invoice.seller.vat_id- Detected by
- tier 3 — KoSIT validator (authoritative)
- Reachability
- Triggerable from your request JSON (generate & validate)
How to fix it
Remove invoice.seller.vat_id and invoice.buyer.vat_id, or correct the lines' vat_category. Without a VAT id, BR-CO-26 then needs invoice.seller.id or invoice.seller.legal_registration_id — the tax number (BT-32) does not count there.
BR-O-02 auf Deutsch — was bedeutet der Fehler?
Die Rechnung enthält Positionen der Kategorie "O" (nicht umsatzsteuerbar); dann dürfen weder eine USt-IdNr. des Verkäufers (BT-31) noch die seines Steuervertreters (BT-63) noch eine USt-IdNr. des Käufers (BT-48) angegeben sein.
So beheben Sie den Fehler
Entfernen Sie invoice.seller.vat_id und invoice.buyer.vat_id — oder korrigieren Sie die vat_category der Positionen. Ohne USt-IdNr. verlangt BR-CO-26 dann invoice.seller.id oder invoice.seller.legal_registration_id — die Steuernummer (BT-32) zählt dort nicht.
Related rules
BR-DE-16— A seller VAT identifier (BT-31), tax registration number (BT-32) or seller tax representative (BG-11) is…BR-S-02— The invoice has standard-rated (S) lines, which require the seller VAT identifier (BT-31), the tax…BR-CO-26— The seller carries none of: VAT identifier (BT-31), legal registration identifier (BT-30) or seller…BR-CO-09— A VAT identifier (seller BT-31, buyer BT-48, or tax representative BT-63) does not start with an ISO 3166-1…BR-AF-02— The invoice has IGIC (L) lines, which require the seller VAT identifier (BT-31), the tax registration number…BR-AF-03— A document-level allowance uses VAT category L (IGIC), which requires the seller VAT identifier (BT-31), the…
Official sources
- XRechnung specification (KoSIT / xeinkauf.de)
- KoSIT validator on GitHub and the XRechnung validator configuration
Every 422 from the API lists the rule id, the path in your request JSON, a plain-language message and a suggested fix — see the docs overview for the report format.
Or try it live: drop any XRechnung XML on the free validator — same KoSIT-backed report, no account.