Poland Sets 2027 Deadline: Simplified Invoices Must Move from Cash Registers to KSeF

Poland will temporarily allow simplified invoices issued from cash registers—including receipts with a buyer’s NIP—to remain outside the mandatory KSeF system until 31 December 2026. Starting 1 January 2027, all simplified invoices must be issued through KSeF, ending the option to generate them directly from cash registers.

The introduction of the National e-Invoicing System (KSeF) in Poland is coming with a few temporary exceptions for simplified invoices. As a reminder, a simplified invoice is an invoice that can be issued from cash registers, in accordance with the fiscalization rules.

Important changes and deadlines:

• Until December 31, 2026: fiscal receipts that include the buyer's Tax Identification Number (NIP) are treated as simplified invoices. Crucially, these receipts will be exempt from the mandatory KSeF system. This means businesses can continue to issue them via traditional cash registers.

From January 1, 2027: the rules change. All simplified invoices—including receipts with an NIP—will be required to be issued through the KSeF system. This means that it will not be possible to issue simplified invoices from cash registers