Poland Transitions to KSeF 2.0: Mandatory
e-Invoicing System Launches February 1st

Poland is set to complete its migration to the updated National e-Invoice System, KSeF 2.0. To facilitate this transition, the Ministry of Finance has announced a final maintenance break for the current 1.0 version during the last week of January.

Transition Timeline:

• January 26–31, 2026: KSeF 1.0 (including the mobile app and authorization module) will be offline. Integrated commercial systems and the e-Microcompany app will also be unavailable.
• January 25, 2026: This is the final deadline for taxpayers to download certificates or assign permissions within the old KSeF 1.0 environment.
• January 28, 2026: The KSeF 2.0 API will be made available for production environment testing, allowing businesses to verify authentication and token generation before the full launch.
• February 1, 2026: KSeF 2.0 becomes the only valid and mandatory system. KSeF 1.0 will be permanently deactivated.

What to do during the break? While the digital system is down, taxpayers can still submit ZAW-FA notifications to their local tax Office to manage basic Access rights. From February 1st, all new authorizations and certificate applications must be processed through the new KSeF 2.0 interface.

https://ksef.podatki.gov.pl/komunikaty-techniczne/komunikat-techniczny-dotyczacy-krajowego-systemu-e-faktur-ksef/