12. Sept. 2025
Poland’s Ministry of Finance announced the important transition timeline for the National e-Invoicing System (KSeF). The KSeF 1.0 test environment will close on September 1, and the new KSeF 2.0 test environment will launch on September 30. The mandatory system will begin on February 1, 2026.
Poland’s digital invoicing infrastructure is undergoing a groundbreaking transformation. The roadmap announced by the Ministry of Finance focuses on completely renewing the country’s electronic invoice system.
Critical Transition Dates
September 1, 2025: KSeF 1.0 test environment closes. New users will have to wait for the KSeF 2.0 test environment.
September 30, 2025: KSeF 2.0 open API testing begins. Financial-accounting system providers will be able to test their software for compatibility with the new system.
October 15, 2025: Users will be able to integrate with the pre-production (DEMO) environment via API KSeF 2.0.
January 26, 2026: Final usage date for KSeF 1.0 production version. A technical break will occur between January 26-31.
Important Innovations in November
The Certificate and Authorization Module (MCU) will launch on November 1, enabling the granting of permissions necessary to use the National e-Invoicing System from February 1, 2026.
Starting November 3, users will be able to test the KSeF 2.0 Taxpayer Application in the test environment. On November 15, the application will be made available in the pre-production environment.
“Wednesdays with KSeF” Education Program
Starting in September, the Ministry of Finance will launch the “Wednesdays with KSeF” training series covering all voivodeships. The trainings, lasting until mid-December, will inform taxpayers about issuing and receiving invoices in KSeF, downloading certificates, and using free tools.
Current KSeF 1.0 production users can continue using the system until the technical break between January 26-31, 2026. From February 1, 2026, the Ministry of Finance will launch the target version of the system: KSeF 2.0.