Poland Publishes Official Timeline for KSeF 1.0 to KSeF 2.0 Transition

On August 29, 2025, the Polish Ministry of Finance published the official roadmap for the transition from KSeF 1.0 to KSeF 2.0, confirming key dates across testing, pre-production, and production environments ahead of mandatory e-invoicing.

The transition starts with the shutdown of the KSeF 1.0 Test environment on September 1, 2025. As a result, no testing will be possible until the KSeF 2.0 Test environment opens later in September.

Environment Timeline

• September 1, 2025: KSeF 1.0 Test environment shut down
• September 30, 2025: KSeF 2.0 Test environment opens for open API testing
• October 15, 2025: KSeF 2.0 Pre-production (Demo) environment becomes available for API connections
• January 26, 2026: KSeF 1.0 Production environment discontinued, ahead of the planned maintenance window from January 26 to 31, 2026
• February 1, 2026: KSeF 2.0 Production environment goes live, aligned with the start of the mandate

Additional System Updates

• A new Certificates and Permissions (MCU) module will launch on November 1, 2025, enabling permission management and the submission and download of KSeF certificates.
• The KSeF Taxpayer Application will be introduced in phases. It will be available in the Test environment from November 3, 2025, and in the Demo environment from November 15, 2025.
• KSeF 2.0 API documentation has been published to support system integrators and software providers during preparation.

With KSeF 2.0 becoming mandatory from February 1, 2026, taxpayers and vendors should align development, testing, and deployment plans with this confirmed transition schedule.