Error code PEPPOL-EN16931-R120
A line amount doesn't add up
Each line amount must equal quantity × net price (per base quantity), plus line charges, minus line discounts.
The official rule
“Invoice line net amount MUST equal (Invoiced quantity * (Item net price/item price base quantity) + Sum of invoice line charge amount - sum of invoice line allowance amount”
Official text, in the language the rule set publishes it in.
Common causes
- The price or quantity was rounded differently from the line amount.
- A line discount is missing from the calculation, or counted twice.
- The unit price includes VAT.
How to fix it
- Recalculate the line: quantity × price, plus line charges, minus line discounts.
- For very small unit prices, use a base quantity (for example a price per 1,000).
Where to fix it in your software
- Banqup:
use a base quantity instead (7,399.33 EUR per 1,000 units), or correct the line
(help page)
From each provider's own help page, read on 25 October 2026. Menus can change; we are not linked to these providers.
Wrong vs. right (UBL)
Wrong
<cbc:InvoicedQuantity unitCode="HUR">12.5</cbc:InvoicedQuantity> <cbc:LineExtensionAmount currencyID="EUR">900.00</cbc:LineExtensionAmount> … <cac:Price> <cbc:PriceAmount currencyID="EUR">75.00</cbc:PriceAmount> </cac:Price>
Right
<cbc:InvoicedQuantity unitCode="HUR">12.5</cbc:InvoicedQuantity> <cbc:LineExtensionAmount currencyID="EUR">937.50</cbc:LineExtensionAmount> … <cac:Price> <cbc:PriceAmount currencyID="EUR">75.00</cbc:PriceAmount> </cac:Price>