Poland requires corrective invoices in KSeF when payment dates change
Poland's tax authority ruled that both incorrect payment dates on invoices and later agreed changes must be corrected through KSeF corrective invoices. The correction does not affect VAT or the amount due, but creates an audit trail.
The Polish Director of National Tax Information has clarified that payment date errors and subsequent payment term changes must be documented through corrective invoices in KSeF, Poland’s e-invoicing system. The correction is formal and does not alter the VAT base or gross invoice value.
Poland’s tax authority has ruled that both incorrect payment dates on invoices and later agreed changes to payment terms must be corrected through the KSeF e-invoicing system.
The Director of National Tax Information issued the guidance on 10 July 2026 (ruling reference 0114-KDIP1-1.4012.365.2026.1.MM). It covers two situations: an invoice issued with the wrong payment date from the start, and an invoice where the parties later agreed to extend the deadline through amendment or email.
When a corrective invoice is required
Article 106j(1)(5) of Poland’s VAT Act requires a corrective invoice when an error is found in an invoice item. The tax authority’s analysis clarifies that “invoice item” is not limited to mandatory information. It can include optional details that are material to the commercial relationship.
Payment dates are commercially material because they determine when payment is due and affect interest calculations, collection processes and enforcement. An incorrect payment date should therefore be corrected. A subsequent agreed change should also be reflected so the invoice remains aligned with the parties’ current arrangement.
How to issue the corrective invoice
Where the original document was issued as a KSeF structured invoice, the corrective invoice should generally also be issued through KSeF. It should:
- Identify the original KSeF invoice
- Show the correct payment date
- Explain whether the correction results from an original error or a later agreement
The correction does not affect the VAT base, output tax or gross consideration. It should therefore be distinguished from value corrections that affect the tax period or require adjustments by the customer.
What businesses should do
Businesses should incorporate a KSeF step into payment-term amendment procedures. Treasury, credit-control and sales teams should not amend contractual due dates without notifying the invoicing function. Systems should also distinguish a changed payment date from amendments to price, discounts or consideration, which may have different VAT-reporting consequences.
The corrective invoice creates a formal audit trail but does not change the taxable amount or the amount the customer owes.