PEPPOL-EN16931-R120:Line amount does not match calculation
The net amount on one of your invoice lines does not match when we recalculate it from the quantity, price, and any line-level discounts or surcharges. This usually means a rounding error or data entry mistake in your accounting system.
Engine Classification
Financial or legal field · Modification blocked by policy
Reason: Line amounts are financial data controlled by your accounting system. Automatically changing these values would create a discrepancy between your invoice and your books, which is an audit risk. Please correct this in your accounting software and re-export.
What is PEPPOL-EN16931-R120?
PEPPOL-EN16931-R120 is a fatal validation rule defined in the EN 16931 specification. It validates the LineExtensionAmount element under Invoice > InvoiceLine in the UBL invoice XML.
When this rule fires, the invoice is non-compliant and will be rejected by Peppol access points and national validation services. The sending system receives a rejection response and the invoice does not reach the buyer.
Target path: XPath: /Invoice/cac:InvoiceLine/cbc:LineExtensionAmount
Why This Error Matters
Invoice will be rejected by PEPPOL validation. Line calculations must be mathematically consistent.
PEPPOL-EN16931-R120 is a hard failure. Invoices that trigger this rule are rejected at the access point and never reach the recipient. In Peppol networks, this means your sending system receives an MLR (Message Level Response) with a rejection status. The invoice must be corrected and re-sent, adding delay to your payment cycle.
Validator Behavior
- ·Causes invoice rejection
- ·Error returned: PEPPOL-EN16931-R120
- ·Specification: EN 16931
How to Fix It
Before / After
<Invoice> <!-- Issue: Invoice line net amount MUST equal (Invoiced quantity × Item --> </Invoice>
<Invoice> <!-- Issue resolved per EN 16931 --> </Invoice>
Technical Reference
XPath: /Invoice/cac:InvoiceLine/cbc:LineExtensionAmountCommon Causes
- ·Line net amount does not match calculation formula
- ·Rounding differences in multiplication
- ·Base quantity not accounted for in calculation
- ·Allowances or charges changed without updating net
- ·Manual override of line net amount
Seeing this in production? The API handles PEPPOL-EN16931-R120 automatically. See the fix response →
Frequently Asked Questions
Line amount must equal quantity × price ± allowances/charges.
Recalculate: Quantity × (Price / BaseQuantity) ± adjustments. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.
Yes, PEPPOL-EN16931-R120 is a critical error that will cause invoice rejection. It must be fixed before submission to ensure your invoice is accepted by the recipient's system.
Many instances of PEPPOL-EN16931-R120 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including line amount calculation error.
See Also
Related Errors
Last updated: 27 February 2026
Handle PEPPOL-EN16931-R120 Automatically in Your Pipeline
The compliance engine auto-remediates this error with controlled safety policies and evidence pack generation.