UBL-CR-476: Do not give an invoice-level discount or charge an amount per unit

What it means

The rule looks at the discounts (BG-20) and charges (BG-21) placed on the whole invoice, directly under the invoice or credit note. It warns when one of them has a cbc:PerUnitAmount, an amount for each unit. EN 16931 gives a discount or charge on the whole invoice one total amount, and optionally the base amount and percentage it was calculated from.

Why it matters

EN 16931 does not use cbc:PerUnitAmount on document-level discounts (BG-20) or charges (BG-21).

How to fix it

Work out the full amount and enter it as the discount amount (BT-92) or the charge amount (BT-99). If the discount is a percentage, you can also give the percentage (BT-94) and the base amount (BT-93). Then delete cbc:PerUnitAmount from each cac:AllowanceCharge directly under the Invoice or CreditNote element. Check the corrected file again.

The rule as published

A UBL invoice should not include the AllowanceCharge PerUnitAmount

Where this rule applies