The platform compares three attributes to determine whether an invoice is a duplicate:

• Invoice date
• Invoice number
• Supplier ID (Chamber of Commerce number or Peppol identifier)

If all three match a previously received invoice, the document is marked as a duplicate and is not forwarded to your accounting software.

Duplicate detection works across all channels. If the same invoice arrives both via Peppol and by email as a PDF, the platform recognises this as a duplicate. The first version is processed; the next is blocked.

This is particularly relevant for organisations that receive invoices through multiple channels. A supplier who sends an invoice both by email and via Peppol will not cause a double posting as a result.

Sometimes a document marked as a duplicate is in fact an original. This can happen if two different invoices happen to share the same invoice number, or if you deliberately want to reprocess the same invoice.

In the platform, you can pass through a blocked duplicate by marking the document as "Mark as original". The invoice is then processed as if it were a new document.

A duplicate may go undetected if the invoice number is recognised differently on the second submission. This can occur if the invoice arrives through a different channel with a different format or scan quality, causing the OCR to interpret the invoice number slightly differently. This is an inherent limitation of recognition on PDF documents.

Tip: if you regularly receive duplicate notifications, check whether your supplier is sending the invoice through multiple channels simultaneously (for example both by email and via Peppol). Agree on a single channel for invoice delivery.