Validation rules

BR-46 — EN 16931 rule

A VAT breakdown (BG-23) has no tax amount (BT-117).

Rule

BR-46 — official EN 16931 / XRechnung rule

Severity

error

Business term

BT-117 — VAT category tax amount

Field in your JSON

invoice.lines

Detected by

tier 3 — KoSIT validator (authoritative)

Reachability

Only reachable when validating your own XML — normbill-generated documents cannot trigger it

The engine always writes BT-117 per breakdown. The UBL schema makes the element mandatory anyway, so the XSD tier reports hand-built XML without it first.

How to fix it

Add cbc:TaxAmount to every cac:TaxSubtotal.

Related rules

• BR-CO-17 — A VAT breakdown's tax amount (BT-117) does not equal its taxable amount (BT-116) multiplied by the category…
• BR-DEC-20 — A VAT category tax amount (BT-117) uses more than 2 decimal places — EN 16931 allows at most 2.
• BR-AE-09 — The tax amount (BT-117) of the reverse-charge (AE) breakdown must be 0.
• BR-AF-09 — The tax amount (BT-117) of an IGIC (L) breakdown must equal its taxable amount (BT-116) multiplied by its…
• BR-AG-09 — The tax amount (BT-117) of an IPSI (M) breakdown must equal its taxable amount (BT-116) multiplied by its…
• BR-E-09 — The tax amount (BT-117) of the exempt (E) breakdown must be 0.

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.