KSeF 2.0 Under Scrutiny: System Rejects Invoices, Ministry of Finance Changes Interpretations

The implementation of the National e-Invoice System in version 2.0 is characterized by numerous technical problems that genuinely hinder business operations. Entrepreneurs report situations where formally correct documents do not reach the repository or are rejected without a clear reason. Experts point out that one of the reasons may be errors in XML file encoding, which forces issuers to resend invoices. This generates enormous operational risk, as these documents may have already been booked in companies' internal systems before receiving a rejection notification from the government gateway. Poland is one of the first European Union countries implementing mandatory e-invoicing on such a large scale, following solutions from Italy, where a similar system has been operating since 2019. The market situation is worsened by an unexpected change in the position of the Ministry of Finance regarding documents issued by entities exempt from VAT. As recently as autumn, the tax authorities allowed the use of traditional receipts, but the latest guidelines deem them insufficient. This means that from April 1, 2026, small entrepreneurs and sole proprietors will find themselves in a kind of tax trap, forced to use a system that still exhibits instability. Although the ministry assures that throughout the entire 2026 it will not impose sanctions for errors in using KSeF, entrepreneurs fear penalties for other formal shortcomings. „Those who create and implement this system predict that it will not work well because they foresee asymmetry from the start.” — Roman Kluska An additional threat is the activity of cybercriminals who exploit the confusion surrounding the new platform. Fake emails impersonating tax authority messages are reaching entrepreneurs' inboxes, aiming to extort data or financial resources. In response to these challenges, the tax administration plans to launch a broad series of training sessions for various industries in March, aimed at familiarizing taxpayers with the new technical and legal requirements. 2026-02-01: large enterprises, 2026-04-01: small and medium-sized enterprises 0 zł — will be the sanctions for KSeF errors throughout 2026 Change in Sales Documentation Rules for VAT-Exempt Entities: : → ; : → [{"dataISO": "2026-02-25", "date": "February 25, 2026", "event": "Free Online Training on KSeF Implementation"}, {"dataISO": "2026-03-01", "date": "March 2026", "event": "Start of Ministry Training Cycle for Industries"}, {"dataISO": "2026-04-01", "date": "April 1, 2026", "event": "KSeF Obligation for Smaller Firms"}] Emphasizing implementation chaos and the oppressiveness of the tax authorities towards the smallest entrepreneurs. | Highlighting the tightening of the tax system and the protective nature of no sanctions in the first year.