What it means
When an item has a standard identifier (BT-157), its scheme must be a four-digit code from the ISO 6523 ICD list, for example 0088 for a GLN, 0060 for a DUNS number, 0106 for a Dutch KvK number or 0009 for a French SIRET. For a GTIN barcode number the scheme is 0160.
Why it matters
Codes are read by software, not by people. A value outside the agreed code list cannot be interpreted, so the recipient's system rejects the invoice even when the value looks sensible to a person.
How to fix it
Mark barcodes in your product data as GTIN so your software writes scheme 0160, and do not use letters such as "GTIN" or "EAN" as the scheme. If you build the XML yourself, it is the schemeID of cac:StandardItemIdentification/cbc:ID (UBL) or of ram:GlobalID (CII).
The rule as published
Item standard identifier scheme identifier MUST belong to the ISO 6523 ICD code list 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 |
| 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-CL-21 still fails, and which other rules do.
Related rules
- BR-CL-22 VAT exemption reason codes must come from the VATEX list
- BR-CL-23 Units of measure must come from UN/ECE Recommendation 20 or 21
- BR-CL-24 Attachments must be PDF, PNG, JPEG, CSV, XLSX or ODS
- BR-CL-25 Electronic address schemes must come from the EAS list
- BR-CL-26 The delivery location scheme must come from ISO 6523
- BR-CL-20 Charge reason codes must come from UNTDID 7161