How to fix BR-27
The Item net price (BT-146) shall NOT be negative.
What this rule checks
The unit price of an item must be zero or positive. A negative price does not make sense in the context of a line item. If you need to represent a discount, use the allowance mechanism (cac:AllowanceCharge with ChargeIndicator set to false) or issue a credit note instead. This rule prevents confusion in automated processing where a negative price could invert the meaning of the transaction.
Referenced business terms
This rule references the following EN 16931 business term. Click through for the full definition, the UBL XPath and the cardinality.
How to fix it
Ensure the cbc:PriceAmount value inside cac:InvoiceLine → cac:Price is zero or positive. For refunds, use a credit note (InvoiceTypeCode 381) instead.
Common causes
- A discount was applied by making the price negative instead of using an allowance.
- A data entry error resulted in a minus sign before the price.
- A credit or return was modeled as a negative price instead of using a credit note.
- An integration mapping incorrectly negated the price field.
Example: before (broken)
<cac:Price>
<cbc:PriceAmount currencyID="EUR">-50.00</cbc:PriceAmount>
</cac:Price>Example: after (fixed)
<cac:Price>
<cbc:PriceAmount currencyID="EUR">50.00</cbc:PriceAmount>
</cac:Price>Related rules
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