How to Cancel an Invoice in KSeF After Issuance?

You issued an invoice in KSeF (Poland's national e-invoicing system), and a moment later you notice it went out twice, or to the wrong customer. You want to cancel the invoice in KSeF, so you look for a "cancel" or "delete" button. There isn't one. Once an invoice has a KSeF number, it is a record in a central government system, not a draft in your software.

What you do next depends on the stage. Before a KSeF number is assigned, you fix the data and resend. After it, you issue a corrective invoice, sometimes a "zero correction". This matters now: most Polish businesses have been invoicing in KSeF since 1 April 2026, and the smallest sole proprietorships (JDG), with up to PLN 10,000 gross in monthly invoiced sales, join on 1 January 2027 (inFakt, in Polish).

I write as a software founder, not as an accountant. This is not tax advice. Where interpretation of the law is involved, I link the source; for your own case, ask your accountant. Status as of 15 October 2026.

Why you can't cancel an invoice in KSeF

A structured invoice counts as issued the moment KSeF validates its structure and assigns a KSeF number (SaldeoSMART, in Polish). From then on it cannot be edited or deleted, even if it was issued entirely by mistake with no underlying transaction (Prawo.pl, in Polish). The buyer cannot reject or withdraw it either (ksef.pl, in Polish).

Correction notes (noty korygujące), which buyers used to issue to fix formal errors, are gone too. The provision (Article 106k of the VAT Act) was repealed from 1 February 2026, so only the seller can fix an invoice (Poradnik Przedsiębiorcy, in Polish).

So in KSeF, "cancel" means "correct". The original invoice stays in the system permanently, and a correction with its own KSeF number sits next to it.

Before the invoice gets a KSeF number

You can only cancel up to the moment a KSeF number is assigned (mBank, in Polish). Before that, the system has no invoice to correct:

Invoice state What it means What to do Draft, not sent Exists only in your software Edit or delete it there Processing KSeF has not assigned a number yet Wait for the result; withdraw the submission if your software allows Rejected KSeF did not assign a number Fix the data and resend Offline24, not yet in KSeF Must be sent by the next business day at the latest (Akademia LTCA) Submit it; you can issue a correction only after it receives a KSeF number (PIT.pl)

In Biurko you can cancel a submission that KSeF has not yet accepted. Once it is accepted, a correction is the only route.

After the number: a corrective invoice instead of cancellation

A correction to a structured invoice must carry the KSeF number of the invoice it corrects (Article 106j(2)(2a)) and is itself issued as a structured invoice or in offline24 mode (Article 106j(4)), per the VAT Act. The Ministry of Finance publishes its own guidance in the KSeF Q&A. Which correction to use depends on the error:

Error How to correct Typo in a name or address that does not change who the buyer is A standard corrective invoice with only the corrected data (Grant Thornton, in Polish) Wrong price, quantity or VAT rate A correction reducing or increasing the invoice (PIT.pl) Wrong buyer NIP (tax ID) A zero correction to the wrong NIP, then a new invoice with the right NIP (PIT.pl) Invoice with no transaction, or issued twice A zero correction (Fakturownia, in Polish)

"Zero correction" is a practical term. The VAT Act does not name it as a separate invoice type (Grant Thornton). Use it when the invoice should not exist in the legal flow at all. If the sale really happened and the buyer is correct, zeroing and reissuing can raise questions with the tax office (Infor, in Polish).

Example (illustrative). The Polish subsidiary of a German group sends the same PLN 12,000 net consulting invoice twice, from two different systems. Both receive KSeF numbers. The second one documents nothing, so the subsidiary issues a zero correction to it. The correction and the second invoice both stay visible in KSeF, and the buyer's accounts payable team must not book the duplicate. If it already did, it has to correct its input VAT (Infor).

Step by step: correcting an invoice that has a KSeF number

1. Find the KSeF number of the original invoice. You need it to link the correction.

2. Choose the type of correction from the table above.

3. Issue the correction in KSeF. For a zero correction, net, VAT and gross values of every line go to zero (mBank). A correction to an invoice with a wrong NIP is addressed to that same wrong NIP (JPK.info.pl).

4. For repeated corrections, point to the original. In the DaneFaKorygowanej section you always give the KSeF number of the original invoice, not of an earlier correction (PIT.pl).

5. For a wrong NIP, issue a new invoice with the correct buyer data.

6. Check the status and the UPO (Urzędowe Poświadczenie Odbioru, the official receipt confirmation) of the correction. Only then is the matter closed.

[screenshot: Biurko invoice list with the "Correct to zero" action on an invoice that has a KSeF number]

How to report the correction for VAT and JPK

This is the step most people skip, and where mistakes happen. Each point below should be confirmed with your accountant:

• A reducing correction issued in KSeF. You lower the tax base in the period in which you issued the correction. You do not need documentation of an agreement with the buyer (PIT.pl).

• Wrong NIP or a duplicated invoice. In individual interpretations of the Director of the National Revenue Information (KIS), the zero correction and the new invoice are reported in the period of the original invoice, because the error existed from the start (podatki.biz, in Polish, Akademia LTCA). An individual interpretation binds only the applicant.

• The buyer. After receiving a zero correction, the buyer must correct its input VAT (Infor).

• An invoice with no transaction. Authorities warn of the risk under Article 108(1) of the VAT Act, the so-called empty invoice (PIT.pl).

Checklist: an error in a KSeF invoice

• Check whether the invoice already has a KSeF number. If not, fix it and resend.

• Record the KSeF number of the original invoice.

• Decide whether the error concerns the buyer's NIP. If so, plan a zero correction and a new invoice.

• Do not zero an invoice when a standard data correction is enough.

• Issue the correction inside KSeF, not outside it, and keep the UPO.

• Report the correction in VAT and JPK in the right period, after checking with your accountant.

Summary and next step

Nothing in KSeF is cancelled or deleted. Before a number, you fix and resend; after it, you issue a correction; for a wrong NIP, you issue a zero correction plus a new invoice. KSeF penalties under Article 106ni are currently due from 1 January 2027, but a draft published on 1 October 2026 would move them to 1 January 2028 (draft on gov.pl). It is not law yet, and the obligation itself stays.

In Biurko you create a zero correction from the invoice itself, and you pull buyer details from the registry by NIP, which lowers the risk of a typo. Try Biurko free for 14 days at biurko.io.

FAQ

Can I delete an invoice from KSeF?

No. An invoice that received a KSeF number stays in the system permanently. You cannot delete or edit it, even if it was issued by mistake. You can only issue a corrective invoice, a zero correction if needed. Both the original and the correction remain visible in KSeF.

Can the buyer reject an invoice in KSeF?

No. The buyer has no technical way to reject or withdraw an invoice received through KSeF. If it is wrong, the buyer has to ask the seller for a correction. Since 1 February 2026 buyers also cannot fix data themselves with a correction note, because notes were repealed.

Can I issue a correction note for a KSeF invoice?

No. The provision on correction notes (Article 106k of the VAT Act) has been repealed since 1 February 2026. Every correction, including a typo in an address, is issued by the seller as a structured corrective invoice. The buyer can only report the error, and the seller then issues the correction in KSeF referencing the original KSeF number.

Does a zero correction remove the invoice from KSeF?

No. A zero correction sets the invoice values to zero, but the original stays in the system. Both documents are visible in KSeF, each with its own KSeF number. The correction must reference the KSeF number of the original invoice.

What if I issued an invoice with the wrong NIP in KSeF?

Issue a zero correction to the wrong NIP, then a new invoice with the correct NIP. KSeF makes the invoice available to whoever holds the NIP you entered, so a standard data correction is not enough. Under KIS interpretations, report both documents in the period of the original invoice.