KSeF penalties: duty in 2027, fines from 2028?

From 1 January 2027, KSeF is mandatory for all taxpayers, with no 10,000 PLN limit. The Ministry of Finance wants to move the art. 106ni VAT Act fines to 1 January 2028, but that is only a draft, and without a new act the fines start in 2027.

Legal status as of 7 October 2026

Ministry of Finance: penalty deferral extended (16.09.2026) Draft UD477 on RCL

The draft moves art. 106ni paras. 1-3 and 5-7 to 1 January 2028, and the act itself is to take effect on 31 December 2026. That leaves one day for publication, so time is short.

What ends on 31 December 2026

In 2026 the art. 145m limit applied: up to 10,000 PLN gross of sales per month could be invoiced outside KSeF. At year end it expires together with art. 145n (cash register invoices and receipts with a NIP). From 2027 there are no cash register invoices, and a receipt with a NIP is no longer a simplified invoice. We covered the limit in our article on the 10,000 PLN limit.

There are few permanent exceptions. Art. 106ga para. 2 of the VAT Act covers, among others, sellers with no seat or permanent establishment in Poland, invoices to private individuals not running a business, special procedures and the art. 113a exemption, and the Ministry of Finance regulation (Dz.U. 2025 item 1740, § 2) adds, among others, invoices for toll motorway travel and single tickets for passenger transport. The VAT exemption under art. 113 does not exclude you from KSeF.

MoF regulation on cases with no structured invoice duty (Dz.U. 2025 item 1740)

What is penalised and how much

Art. 106ni para. 1 lists three situations:

1. You did not issue a structured invoice in KSeF.
2. In emergency mode, during unavailability or in offline24 mode, you issued an invoice that does not match the template.
3. You did not send an invoice issued in offline24, emergency mode or during unavailability on time.

The deadlines behind point 3 are the next working day for offline24 and for unavailability (counted from its end), and 7 working days from the end of an outage in emergency mode.

The fine is up to 100% of the VAT shown on the invoice issued outside KSeF. If the invoice shows no VAT, it is up to 18.7% of the total amount due. The head of the tax office imposes it by decision, you pay within 14 days of delivery, and the money goes to the state budget.

For Ania it looks like this. A 12,300 PLN gross invoice with 2,300 PLN VAT issued outside KSeF has a ceiling of 2,300 PLN. A 500 PLN invoice from a VAT-exempt taxpayer has a ceiling of 93.50 PLN. That is a maximum, not a rate: the office applies the Code of Administrative Procedure rules on administrative fines, including art. 189d (factors for setting the amount), and where the violation is of negligible weight and has stopped it may issue a warning instead (art. 189f). These violations do not lead to fiscal crime or fiscal offence proceedings (para. 4).

VAT Act, consolidated text, art. 106ni

If UD477 passes and if it does not

The last row concerns a total outage. Invoices from it are not entered into KSeF afterwards, so the draft's explanatory memorandum speaks of eliminating an "oczywisty błąd" (obvious error).

No fine is not no consequences

The Ministry wrote plainly: "Odroczenie kar nie oznacza braku obowiązku stosowania KSeF" (deferring fines does not mean KSeF need not be used). In 2027 the National Revenue Administration is to support and remind first, but officials "będą reagować w przypadkach wystawiania faktur poza KSeF" (will react to invoices issued outside KSeF) and check whether not using the system leads to unreliable tax settlement.

The seller still owes the VAT on an invoice issued outside KSeF, and according to the Ministry the breach falls, as a rule, on the issuer.

The buyer, such as your accountant Ms Krystyna, is in a better position. In its "Najczęstsze pytania" (frequently asked questions) the Ministry states that the right to deduct remains, provided the art. 86 conditions are met and no art. 88 negative conditions apply. A missing KSeF invoice is there a "formal defect", and the buyer need not ask the seller to issue one. At the same time such an invoice is a "warning signal" and may raise the risk that the whole transaction is checked. Only the sentence on sanctions is limited in time ("za 2026 rok nie będą nakładane sankcje za błędy popełnione podczas korzystania z KSeF", meaning no sanctions for mistakes made while using KSeF in 2026). The deduction answers carry no time limit.

In practice: keep proof of the transaction (payments, protocols, correspondence) and note the suppliers who still invoice outside KSeF.

Ministry of Finance: KSeF, frequently asked questions

What to do before 1 January 2027

Check that your invoicing software supports KSeF emergency and offline24 modes. The art. 106ni point 3 deadlines are short, so you need a procedure for when the system is unavailable. Offline mode needs a type 2 KSeF certificate obtained beforehand.

Tokens are allowed by the regulation until 31 December 2026 (§ 13). The KSeF 2.0 Handbook part I (06.08.2026, p. 26) says the Ministry "zdecydowało o zachowaniu tej metody uwierzytelniania na czas nieokreślony" (decided to keep this authentication method indefinitely) and that the regulation "zostanie odpowiednio znowelizowane" (will be amended accordingly). The amendment has not been published yet. So do not rely on a token alone; we explain the differences in certificates vs tokens in KSeF.

If you generate XML yourself, check it in the ksefuj.to validator before sending.

A sole trader unsure where to start? Begin with KSeF for sole traders (JDG).