Validation rules
BR-CO-04
An invoice line is not categorized with a VAT category code (BT-151).
- Rule
BR-CO-04— official EN 16931 / XRechnung rule- Severity
- error
- Business term
BT-151— Line VAT category- Field in your JSON
invoice.lines[*].vat_category- Detected by
- tier 3 — KoSIT validator (authoritative)
- Reachability
- Only reachable when validating your own XML — normbill-generated documents cannot trigger it
The engine derives a category for every line it serializes; a line with neither vat nor vat_category is stopped at tier 1 (NB-VAT-RATE) before generation.
How to fix it
Add cac:ClassifiedTaxCategory with a UNCL 5305 code (S, Z, E, AE, K, G, O, L, M) to the line's cac:Item.
BR-CO-04 auf Deutsch — was bedeutet der Fehler?
Eine Rechnungsposition ist keiner Umsatzsteuer-Kategorie (BT-151) zugeordnet.
So beheben Sie den Fehler
Ergänzen Sie cac:ClassifiedTaxCategory mit einem UNCL-5305-Code (S, Z, E, AE, K, G, O, L, M) im cac:Item der Position.
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.