What it means
The item net price (BT-146) on every invoice line must be zero or more. A refund, a return or a discount is shown with a negative quantity or as an allowance, never with a negative price.
Why it matters
EN 16931 defines prices as non-negative so that the line amount is always quantity times price. A negative price makes the buyer's software book the line the wrong way round, so the invoice is rejected.
How to fix it
For a returned item or a refund, keep the price positive and enter a negative quantity, for example -1 at 25.00. For a discount, use a line discount or a discount on the whole invoice instead of a line with a negative price. If you want to cancel a whole invoice, issue a credit note instead.
The rule as published
The Item net price (BT-146) shall NOT be negative. Where CIUS-RO UBL Invoice 1.0.9, CIUS-RO UBL Credit Note 1.0.9 run it, the rule reads:
Preţul net al articolului (BT-146) trebuie să NU fie negativ. #The Item net price (BT-146) shall NOT be negative. ( = ' … ') Business terms: BT-146
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 BASIC | 1.0.9-2 |
| Factur-X 1.09 EN 16931 | 1.0.9-2 |
| ZUGFeRD 2.5 BASIC | 2.5.2 |
| ZUGFeRD 2.5 EN 16931 | 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-27 still fails, and which other rules do.