errorubl-2.1

UBL-CR-003:Duplicate invoice line ID

Each invoice line must have a unique ID within the invoice. Duplicate IDs found.

We can fix this automatically

AUTO-FIX

Auto-fix: Remove the disallowed element from the invoice XML. No data loss occurs because EN16931 explicitly prohibits this element.

No manual changes needed
Upload and Fix Now

Why This Error Matters

Invoice will be rejected by PEPPOL/EN16931 validators. Safe to remove - this element is explicitly prohibited and contains no required business data.

How to Fix It

1

Check line IDs

List all InvoiceLine/ID values

2

Find duplicates

Look for repeated numbers

3

Renumber

Use sequential unique numbers (1, 2, 3...)

Code Example

<cac:InvoiceLine>
  <cbc:ID>1</cbc:ID>
  <!-- unique per line -->
</cac:InvoiceLine>
<cac:InvoiceLine>
  <cbc:ID>2</cbc:ID>
  <!-- different from first -->
</cac:InvoiceLine>

Technical Details

XPath: /Invoice/cac:InvoiceLine/cbc:ID

Common Causes

  • Source ERP exports full UBL 2.1 instead of EN16931 subset
  • Generic UBL template includes optional elements not needed for e-invoicing
  • Conversion from another format added unsupported elements
  • Manual XML editing introduced non-standard elements
  • Invoice software not configured for EN16931 compliance

Commonly Seen In

All invoicing software

Frequently Asked Questions

Each invoice line must have a unique ID within the invoice. Duplicate IDs found.
Ensure each invoice line has a unique identifier. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.
Yes, UBL-CR-003 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 UBL-CR-003 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including duplicate invoice line id.
UBL-CR-003 is commonly seen in exports from All invoicing software. These software packages sometimes generate invoices that need adjustment to meet full compliance standards.

Related Errors

BR-16

Invoice line must have an identifier

UBL-CR-001

Invalid XML Syntax

Last updated: 16 January 2026

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