Hatice Ozcan
Jul 8, 2025
KSeF 2.0 and FA(3) Finalized – Poland Kicks Off E-Invoicing Rollout
Poland is officially moving ahead with its e-invoicing mandate. On June 30, the Ministry of Finance released the complete technical documentation required for businesses and software providers to begin implementing the updated KSeF platform (Krajowy System e-Faktur).
The Polish e-invoicing model follows a three-corner structure: invoices are sent by the issuer to the KSeF system, validated, assigned a unique number, delivered to the recipient, and archived for 10 years.
Implementation Tools Now Available
The newly published package builds on earlier drafts and now includes:
Final KSeF 2.0 API specifications
SDKs for Java and .NET
Sample integration code
Full OpenAPI documentation
Developer guides and support materials
All resources are available via the KSeF portal, and the Ministry strongly encourages companies to begin preparation and testing in the sandbox environment.
Timeline and Rollout Plan
June 25, 2025: Legislation submitted to Parliament
September 30, 2025: Test environment and API testing phase begins
November 2025: Production environment goes live, issuer certificates issued
February 1, 2026: FA(3) becomes mandatory for large taxpayers (2024 turnover > PLN 200M / ~€47M)
April 1, 2026: Extended to all other businesses (with some exceptions)
January 2027: Final deadline for micro-businesses and full KSeF integration including POS systems
There will be a grace period until January 2027, during which no penalties will apply for non-compliance.
With the full technical framework now in place, the time for businesses to act is now. Early implementation will ensure smoother onboarding and compliance when the mandate becomes enforceable.