Fiscal subject related
E-invoicing in Poland: as of 1st September, the test version of the National e-Invoice System (KSeF) 1.0 has been officially deactivated, paving the way for the launch of KSeF 2.0, the next-generation platform designed to improve invoice processing and integration with commercial accounting systems.
Transition Timeline:
· September 1, 2025: KSeF 1.0 test environment deactivated. New users must wait for access to the KSeF 2.0 test system.
· September 30, 2025: Open testing of the KSeF 2.0 API begins, allowing software providers to evaluate system compatibility.
· October 15, 2025: Users can begin integrating with the pre-production (DEMO) environment via the new API.
· January 26–31, 2026: Scheduled maintenance break for the current production system.
· February 1, 2026: Official launch of the KSeF 2.0 production system.
KSeF 2.0 introduces improved capabilities for exchanging data between the national platform and third-party invoicing systems. The new API is designed to streamline integration, improve security, and support broader adoption across Poland’s financial and business sectors.
The Ministry has already published the full API documentation to assist developers and integrators in preparing for the transition. It is available at:
https://ksef.podatki.gov.pl//ksef-na-okres-obligatoryjny/wsparcie-dla-integratorow/
Also, it is important to mention that the Polish president on 27 August 2025 signed and completed the adoption of the KSeF e-invoicing amending legislation. The legislation, which amends the VAT Act, will be shortly published in the official SEJM as the final step.
This sets the launch date for phase one of the Polish e-invoicing mandate for 1 February 2026. Smaller companies join the mandate on 1 April 2026.
Other news from Poland
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