What it means
The invoice can name the seller's tax representative (BG-11), the person or company the seller has appointed to account for VAT on its behalf. In UBL a postal address can carry a PO box number as its own element. EN 16931 has no separate PO box field, so the address is given as address lines, city, postcode, country subdivision and country. The rule fails when cac:TaxRepresentativeParty/cac:PostalAddress/cbc:Postbox is in the file at all, even if empty.
Why it matters
EN 16931 does not use a separate PO box field for the tax representative's address. A PO box can be included in an address line instead.
How to fix it
If the PO box is part of the address, include it in an address line, such as the first address line (BT-64), cbc:StreetName, for example 'PO Box 123'. Remove cbc:Postbox from cac:TaxRepresentativeParty/cac:PostalAddress and recheck the corrected file.
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 TaxRepresentativeParty PostalAddress Postbox 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-307 still fails, and which other rules do.
Related rules
- UBL-CR-308 Leave the separate floor field out of the tax representative's address
- UBL-CR-309 Leave the separate room field out of the tax representative's address
- UBL-CR-310 Leave the separate block name field out of the tax representative's address
- UBL-CR-311 Leave the separate building name field out of the tax representative's address
- UBL-CR-312 Leave the separate building number field out of the tax representative's address
- UBL-CR-313 Leave the separate in-house mail field out of the tax representative's address