What it means
This rule checks the buyer's contact block in a UBL invoice or credit note (cac:AccountingCustomerParty, cac:Party, cac:Contact). It must not contain cbc:Telefax. The standard has fields for the buyer's telephone number (BT-57) and email address (BT-58), but not for a fax number.
Why it matters
The check is limited to the fax element in the buyer's contact details. It does not establish whether the contact is reachable or require another contact method to clear this warning.
How to fix it
Configure your UBL export to omit the buyer contact's fax element. Keep any existing telephone number or email address. If you edit or generate the XML, remove cbc:Telefax from cac:AccountingCustomerParty/cac:Party/cac:Contact. Recheck the file in Klarbon.
Once the file is corrected, check it again for free: Validate an invoice against EN 16931
Or fix the invoice in a form and download the corrected file, for 1 credit: Fix a rejected e-invoice
The rule as published
A UBL invoice should not include the AccountingCustomerParty Party Contact Telefax Where this rule applies
| Rule set | Version |
|---|---|
| EN 16931 (UBL) | 1.3.17 |
| EN 16931 (UBL credit note) | 1.3.17 |
| XRechnung 3.0 (UBL) | 3.0.2 |
| XRechnung 3.0 (UBL credit note) | 3.0.2 |
| Peppol BIS Billing 3.0 (invoice) | 2026.5 |
| Peppol BIS Billing 3.0 (credit note) | 2026.5 |
| SI-UBL 2.0 / NLCIUS (invoice) | 2.0.3.13 |
| SI-UBL 2.0 / NLCIUS (credit note) | 2.0.3.13 |
| France CTC (UBL invoice) | 1.4.0-04 |
| France CTC (UBL credit note) | 1.4.0-04 |
| CIUS-RO UBL Invoice 1.0.9 | 1.0.9 |
| CIUS-RO UBL Credit Note 1.0.9 | 1.0.9 |
Check your file
Drop your e-invoice to see whether UBL-CR-254 still fails, and which other rules do.
Related rules
- UBL-CR-255 Leave the note on the buyer's contact out
- UBL-CR-256 Leave other communication channels for the buyer contact out
- UBL-CR-257 Leave person details out of the buyer party
- UBL-CR-258 Leave the buyer's agent party out
- UBL-CR-259 Leave the buyer's service provider party out
- UBL-CR-260 Leave the buyer's power of attorney out