errorEN 16931

BR-15:Invoice line quantity required

The Amount due for payment (BT-115) is required.. Check the `cbc:PayableAmount` element in your invoice XML.

Severity
Fatal
Rule set
EN 16931
Country
All EU
Fix type
BLOCKED

Engine Classification

Financial or legal field · Modification blocked by policy

Reason: Line amounts require manual verification. Changes affect tax calculations and invoice totals. Verify the correct values in your invoicing system before correcting.

What is BR-15?

BR-15 is a fatal validation rule defined in the EN 16931 specification. It validates the InvoicedQuantity 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:InvoicedQuantity

This error requires manual correction — financial fields are protected by policy.Test This Error ↓

Why This Error Matters

Invoice rejected. This tells the buyer exactly what to pay and is essential for payment processing.

BR-15 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: BR-15
  • ·Specification: EN 16931

How to Fix It

1.

Set quantity

Number of units invoiced

2.

Add unit code

Use UN/ECE Rec 20 codes (C62, EA, KGM, etc.)

3.

Common units

C62=unit, EA=each, KGM=kilogram, MTR=meter

Before / After

Failing XML
<cac:LegalMonetaryTotal>
  <!-- cbc:PayableAmount is missing -->
</cac:LegalMonetaryTotal>
Corrected XML
<cac:LegalMonetaryTotal>
  <cbc:PayableAmount>valid-value</cbc:PayableAmount>
</cac:LegalMonetaryTotal>

Technical Reference

XPathXPath: /Invoice/cac:InvoiceLine/cbc:InvoicedQuantity
SpecEN 16931
StrategyBLOCKED: This is the payment amount. We never auto-calculate because it may involve prepayments, deposits, or adjustments that only your accounting system knows about. Must come from source.

Code Example

<cbc:InvoicedQuantity unitCode="C62">10</cbc:InvoicedQuantity>

Common Causes

  • ·Payable amount not calculated in source system
  • ·Prepayment/deposit deductions not factored in
  • ·PayableAmount field not mapped in export template
  • ·Partial payment scenario not handled in calculation
  • ·Rounding adjustment not applied to final amount

Seeing this in production? The API handles BR-15 automatically. See the fix response →

Commonly Seen In

All invoicing software

Frequently Asked Questions

Each invoice line must have an invoiced quantity with unit of measure.

Add InvoicedQuantity with unitCode attribute. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.

Yes, BR-15 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 BR-15 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including invoice line quantity required.

BR-15 is commonly seen in exports from All invoicing software. These software packages sometimes generate invoices that need adjustment to meet full compliance standards.

See Also

EN 16931 Validator

Check your invoice now

Related Errors

BR-14

Invoice line net amount required

BR-16

Invoice line must have an identifier

Last updated: 27 February 2026

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