XRechnung requires payment instructions (BG-16) — usually credit transfer details with IBAN.
UBL: cac:PaymentMeans with PaymentMeansCode (e.g. 58 for SEPA) and PayeeFinancialAccount/ID (IBAN).
The Billhorse validator checks XRechnung, ZUGFeRD and Factur-X right in your browser — your file is never uploaded.
Open the validator← All validation rules
Rule source: EN 16931 / XRechnung (KOSIT) or Billhorse check (BH-*).