KSeF (Krajowy System e-Faktur) is Poland’s National Electronic Invoicing System, a government-mandated platform for issuing and registering electronic invoices. The system has been introduced to modernize and standardize invoice reporting, improve transparency, and ensure that all VAT invoices are properly recorded in the official tax infrastructure.
From April 1, 2026, all businesses operating in Poland will be required to register their invoices through KSeF. This requirement applies to virtually all VAT taxpayers with a seat or permanent establishment in Poland, regardless of company size.
KSeF is a legal obligation established by Polish tax law. Its primary goals are to:
Standardize the invoicing process across businesses, using a structured electronic format.
Improve accuracy and traceability of tax documents.
Reduce tax fraud and streamline VAT reporting.
Support the digital transformation of tax administration in line with European e-invoicing standards.
Once an invoice is successfully registered in KSeF, it receives a unique KSeF reference number that confirms it has been officially recorded in the government system.
For our clients, the introduction of KSeF does not change the way you receive, use, or account for invoices. Invoices remain fully valid and acceptable for all accounting, tax, and business purposes.
KSeF Reference Number: Each invoice will include a unique KSeF number indicating that it has been registered in the national system.
QR Code: In many cases, the invoice will also include a QR code. This QR code links directly to the official government record for the invoice, allowing you (or your accountant) to verify that all details have been correctly recorded in KSeF.
In normal operations, invoices are transmitted to KSeF online at the time of issuance. However, the regulations also allow for certain offline or emergency modes if the KSeF system is temporarily unavailable or if connectivity issues occur.
In these situations:
The invoice may be signed and issued offline and then submitted to KSeF within the legally required timeframe (e.g., by the next business day).
In such cases, it is possible that two QR codes may appear on the invoice: one linked to the offline issuance and one confirming later registration in the KSeF system.
This ensures full compliance with legal requirements and transparency, even when the standard online submission is temporarily unavailable.
KSeF is a compliance requirement designed to confirm that your invoices are properly registered in the government’s official e-invoicing system. It does not introduce any additional obligations for you as a customer, nor does it affect the validity or usability of the invoice. The presence of the KSeF number and, where applicable, QR codes simply provides an added assurance that the invoice has been officially recorded and is fully compliant with current tax law.