Validation rules

BR-15

The amount due for payment (BT-115) is missing from the document totals.

Rule

BR-15 — official EN 16931 / XRechnung rule

Severity

error

Business term

BT-115 — Amount due (computed: BT-112 − BT-113)

Field in your JSON

invoice.paid_amount

Detected by

tier 3 — KoSIT validator (authoritative)

Reachability

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

The serializer always writes BT-115. The UBL schema makes cbc:PayableAmount mandatory anyway, so the XSD tier reports hand-built XML without it first.

How to fix it

Add cbc:PayableAmount to cac:LegalMonetaryTotal.

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.