What it means
The despatch advice reference (BT-16) points at the despatch advice, the document that lists what was sent. In a UBL invoice or credit note it is cac:DespatchDocumentReference. This rule checks that the block does not carry an attachment (cac:Attachment), such as an embedded file or a link. Attachments belong with the supporting documents (BG-24).
Why it matters
EN 16931 does not use attachments inside the despatch advice reference.
How to fix it
If the buyer should receive the document, add it as a supporting document (BG-24). Then clear it from the despatch advice reference. If you build the XML yourself, delete cac:Attachment from cac:DespatchDocumentReference and, if needed, add a cac:AdditionalDocumentReference with the attachment directly under the invoice or credit note. Then check the file again.
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 DespatchDocumentReference Attachment 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-057 still fails, and which other rules do.
Related rules
- UBL-CR-058 The despatch reference should not include a validity period
- UBL-CR-059 The despatch reference should not include an issuer party
- UBL-CR-060 The despatch reference should not include a verification result
- UBL-CR-061 Do not add a copy flag to the receiving advice reference
- UBL-CR-062 Do not add a UUID to the receiving advice reference
- UBL-CR-063 Do not add an issue date to the receiving advice reference