What it means
The invoice has none of the identifiers that tell the buyer's system who you are: a seller identifier (BT-29), a company registration number (BT-30) or a VAT number (BT-31).
Why it matters
The buyer's software matches incoming invoices to its suppliers by these numbers. Without any of them it cannot recognise you and the invoice is rejected.
How to fix it
Add at least one: your VAT number (for example DE123456789), your company registration number (such as a Handelsregister, SIREN, KBO or KvK number), or an identifier the buyer has given you. Most businesses simply add their VAT number.
The rule as published
In order for the buyer to automatically identify a supplier, the Seller identifier (BT-29), the Seller legal registration identifier (BT-30) and/or the Seller VAT identifier (BT-31) shall be present. Business terms: BT-29, BT-30, BT-31
Where this rule applies
| Rule set | Version |
|---|---|
| EN 16931 (UBL) | 1.3.17 |
| EN 16931 (UBL credit note) | 1.3.17 |
| EN 16931 (CII) | 1.3.17 |
| XRechnung 3.0 (UBL) | 3.0.2 |
| XRechnung 3.0 (UBL credit note) | 3.0.2 |
| XRechnung 3.0 (CII) | 3.0.2 |
| Peppol BIS Billing 3.0 (invoice) | 2026.5 |
| Peppol BIS Billing 3.0 (credit note) | 2026.5 |
| Factur-X 1.09 MINIMUM | 1.0.9-2 |
| Factur-X 1.09 BASIC WL | 1.0.9-2 |
| Factur-X 1.09 BASIC | 1.0.9-2 |
| Factur-X 1.09 EN 16931 | 1.0.9-2 |
| Factur-X 1.09 EXTENDED | 1.0.9-2 |
| ZUGFeRD 2.5 MINIMUM | 2.5.2 |
| ZUGFeRD 2.5 BASIC WL | 2.5.2 |
| ZUGFeRD 2.5 BASIC | 2.5.2 |
| ZUGFeRD 2.5 EN 16931 | 2.5.2 |
| ZUGFeRD 2.5 EXTENDED | 2.5.2 |
| SI-UBL 2.0 / NLCIUS (invoice) | 2.0.3.13 |
| SI-UBL 2.0 / NLCIUS (credit note) | 2.0.3.13 |
| NLCIUS (CII) | 1.0.3.13 |
| France CTC (UBL invoice) | 1.4.0-04 |
| France CTC (UBL credit note) | 1.4.0-04 |
| France CTC (CII) | 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 BR-CO-26 still fails, and which other rules do.
Related rules
- BR-AE-02 Reverse-charge lines need both VAT numbers
- BR-AE-03 Reverse-charge invoice discounts need both VAT numbers
- BR-AE-04 Reverse-charge invoice charges need both VAT numbers
- BR-AF-02 IGIC lines need a tax number for the seller
- BR-AF-03 IGIC discounts on the whole invoice need a seller tax number
- BR-AF-04 IGIC charges on the whole invoice need a seller tax number