Duplicity

What should I do if I receive a duplicate e-invoice?

⚠ Machine-translated answer, not yet manually reviewed. For the exact wording, see the Slovak original.

Short answer

Do not silently discard the document and do not post or pay it again. Mark it as a possible duplicate and compare the supplier, invoice number, amounts, date, payment reference and XML hash. Then establish whether it is a repeated delivery of the same document or a different document using an incorrect invoice number.

Identity

Supplier and number

The first test is the same supplier and invoice number.

Content

Amount and date

Compare the total amount, VAT, currency and maturity.

Hash

Same or changed XML

The same hash means the same file; changed hash requires attention.

Payment

Duplication blocking

A duplicate document may not create a second payment order.

Detailed explanation

Duplicates may arise due to technical issues such as repeated delivery, re-export from the portal, or a supplier error. The system should be able to distinguish between identical XML files and similar invoices. It is important to prevent duplicate accounting and payment.

As set out in the Act

Correct accounting and VAT deduction require that the same document is not processed more than once. The electronic format allows for better control of duplicates via identifiers and hashes, provided this data is retained.

Practical examples

  • The same XML document was received twice via the delivery channel; the second receipt is marked as a duplicate.
  • The supplier sent a corrected XML file with the same number without explanation, so the company is requesting clarification.
  • The accounts department has already recorded the invoice; the system will block the new import.

Most common mistakes

  • “I’ll simply delete the duplicate invoice.” Even the decision regarding duplication must have an audit trail.
  • “The same number always means the same document.” The content and hash must also be compared.
  • “If the second invoice is in XML, it’s probably the correct one.” The format does not determine the order or correctness.

Conclusion

Place a possible duplicate on hold, compare and document it so that it cannot produce duplicate posting or payment.

Legal basis

  • Act No. 431/2002 Coll. on accounting, verifiability of accounting records
  • Act No. 222/2004 Coll. on VAT
  • Internal control rules for duplicates

Related questions

    This is not legal advice. Sources: Act No. 222/2004 Coll. on VAT, Slovak Financial Administration e-invoicing FAQ, OpenPeppol BIS Billing 3.0 and the Slovak e-Invoicing Centre’s internal validation model. Verified on 7 July 2026.