PEPPOL-EN16931-R120:Line amount does not match calculation
Fix: Review your Invoice XML structure and correct the issue described by this rule. Check relevant cbc: and cac: elements per EN 16931 (PEPPOL-EN16931-R120).
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 rejected by Peppol access points and never reaches 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 — the invoice must be corrected and re-sent before it can reach the recipient.
Peppol access points and tax authorities reject invoices where line amounts do not match the calculation formula. This is a financial accuracy issue that auditors will flag.
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.
Review your Invoice XML structure and correct the issue described by this rule. Check relevant cbc: and cac: elements per EN 16931 (PEPPOL-EN16931-R120). This error involves a protected field — Invoice Navigator flags it in your pipeline so your team can correct it at the source.
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.
PEPPOL-EN16931-R120 involves a financial or legal field that cannot be auto-modified by policy. Invoice Navigator detects and flags this error immediately, but the correction must be made manually in your ERP or invoicing software.
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Last updated: 31 March 2026
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