Poland’s Finance Ministry has published a VAT amendment bill (government project no. UD477) that would bring two major changes from 1 January 2027. First, the obligation to issue invoices through KSeF would extend to every active VAT payer. Second, cash registers would lose the ability to issue invoices at all, leaving only receipts at the point of retail sale, with every invoice having to go through KSeF instead. Financial penalties for not using KSeF would be postponed until the end of 2027, but that does not mean businesses can skip preparing for it.

What changes for cash registers from 1 January 2027

From the new year, a cash register will no longer be able to issue an invoice, only a receipt, and anyone who needs an invoice will have to get it through KSeF. Michał Sosnowski, business development director at Exorigo-Upos, notes that this is a minor change for customers but a revolution for cash register manufacturers and retail chains, since invoicing features have to be stripped from the software, daily reporting has to be rebuilt, and hundreds of device models have to go through certification again at the Central Office of Measures. Crucially, there is no transition period at all, the switch has to happen exactly at midnight between 31 December and 1 January. For anyone running a sole proprietorship (JDG) with retail sales, this is a signal to check now whether their register and point-of-sale system will be ready in time.

How tax authorities will check KSeF compliance

The bill sets out a two-step supervision process. First, the National Revenue Administration (KAS) will individually notify taxpayers and remind them of the KSeF invoicing duty. If a business ignores the reminder, KAS will check whether avoiding KSeF is leading to irregularities in output and input VAT. Zuzanna Niełacna, an accounting and tax expert at fillup k24, warns that VAT-exempt businesses are not invisible to the tax office because of this, since if a seller fails to send an invoice to KSeF but the buyer records it in their own books, the tax office will still find out through cross-checking transactions. This mechanism complements the automatic data matching we describe in our article on how the tax inspectorate will automatically spot your B2B contracts.

What penalties still apply despite the delayed sanctions

Monika Piątkowska, a tax advisor at e-pity, explains that once the protective period ends, issuing an invoice outside KSeF can eventually trigger a penalty of up to 100% of the tax shown on that invoice, or up to 18.7% of the total amount due if no tax is shown. Even during 2027, taxpayers can still be penalised for other mistakes, such as a mismatch between the PDF visualisation and the invoice’s XML structure, or accidentally entering the same document into circulation twice, which authorities can classify as a so-called empty invoice carrying criminal liability under the criminal code. Kajetan Kubicz of LTCA points out that micro-entrepreneurs will be immediately visible to the tax office, since invoices issued outside KSeF must be flagged as BFK in the JPK_VAT report. The underlying tax these invoices document is covered in our article on VAT in Poland.

Legal status as of 1 October 2026. The changes described are a published bill amending the VAT Act (government project no. UD477). Postponing KSeF penalties until the end of 2027 and ending cash register invoicing from 1 January 2027 are currently a bill, not law in force, and may still change during the legislative process.

Author: Walery Kusznirski, in-house legal practitioner at MojaFirma.