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 cac:OtherCommunication, a block for further ways to reach the contact, such as a messaging service. For communication details, the standard has fields for the telephone number (BT-57) and email address (BT-58).
Why it matters
The rule excludes OtherCommunication blocks from the buyer's contact details. It does not require you to add both a telephone number and an email address to clear this warning.
How to fix it
Configure your UBL export to omit OtherCommunication blocks from the buyer's contact details. Keep any existing telephone number and email address. If you edit or generate the XML, remove every cac:OtherCommunication 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 OtherCommunication 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-256 still fails, and which other rules do.
Related rules
- 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
- UBL-CR-261 Leave the buyer's bank account details out
- UBL-CR-262 The invoice should not include a delivery contact for the buyer