What it means
The buyer trade name (BT-45) is the name the buyer trades under, when it differs from its registered legal name (BT-44). It sits in cac:PartyName/cbc:Name inside the buyer party (cac:AccountingCustomerParty) and may appear only once on the invoice or credit note.
Why it matters
EN 16931 allows at most one buyer trade name on an invoice or credit note.
How to fix it
Open the customer record in your invoicing software and look for a duplicated name, for example a trading name that is also exported as a second name. Keep the trade name once and put the legal name in the registered name field. In the XML, cac:AccountingCustomerParty/cac:Party may contain at most one cac:PartyName/cbc:Name.
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
Buyer trade name shall occur maximum once 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-SR-40 still fails, and which other rules do.
Related rules
- UBL-SR-42 A seller can have at most two tax scheme entries
- UBL-SR-43 Only the invoiced object reference may carry a scheme identifier
- UBL-SR-44 An invoice can have only one payment reference
- UBL-SR-45 Only one due date in the payment means
- UBL-SR-46 The payment means text can only be given once
- UBL-SR-47 All payment means codes on an invoice must be the same