January 1, 2027, will mark the completion of the implementation of the Polish mandatory e-invoicing system. Poland began the process of introducing mandatory B2B electronic invoicing in 2023, when the President signed legislation amending the VAT Act.
The original plan envisaged that all VAT-registered businesses would be required to issue and receive e-invoices through the National e-Invoicing System (KSeF) from July 2024. However, technical and implementation challenges led to delays in the rollout. On March 31, 2025, the Polish Ministry of Finance responded to a parliamentary inquiry concerning the implementation timeline, outlining the key dates and next steps for introducing mandatory e-invoicing.
The Final Stage of Implementing KSeF
From January 1, 2027, Poland will require all taxable persons to issue invoices through the KSeF system. Until December 31, 2026, taxable persons may issue invoices outside KSeF, either on paper or electronically, provided that the total monthly value of sales, including VAT, covered by those invoices does not exceed PLN 10,000 (around EUR 2,300).
Another important change concerns receipts containing a Tax Identification Number. From January 1, 2027, these receipts will no longer qualify as simplified invoices, meaning businesses will need to adapt their invoicing procedures accordingly.
In its latest announcement, the Tax Administration Chamber in Wrocław reminded businesses to prepare for the new requirements. To help with this, taxable persons can consult the official KSeF website. The “Understand KSeF 2.0” section provides practical guidance, answers to frequently asked questions, and information on how to issue and access invoices under the updated system.
Conclusion
With the final stage of KSeF implementation approaching on January 1, 2027, businesses operating in Poland must proactively adapt their financial systems and processes. Understanding the updated timelines, adjusting invoicing practices, and leveraging official resources will be essential to ensure compliance and a smooth transition to mandatory e-invoicing.
