Poland’s e-invoicing system is based on a three-corner model, with invoices submitted by the sender to the government-run KSeF (Krajowy System e-Faktur) platform. The platform validates each invoice, assigns it a unique identifier, ensures delivery to the recipient, and archives it for 10 years.
Everything needed for implementation now available
On June 30, the Polish Ministry of Finance published the full set of technical specifications required for businesses and software providers to begin implementation of the KSeF platform. Building on previous developments, including the draft FA(3) schema published in May 2025, the Ministry has now released the complete technical package, including:
- KSeF 2.0 API specifications
- Developer tools and SDKs for Java and .NET
- Integration code examples
- Detailed OpenAPI documentation
- Implementation guidance and supporting materials
With these resources now available, companies and software providers are encouraged by the Ministry to soon start preparing their systems and begin testing within the sandbox environment. All materials can be accessed on the KSeF online portal.
Next steps: Legal process and phased rollout
The legislation draft was submitted to Parliament on June 25 and is expected to be passed into law in July 2025. The planned timeline is as follows:
- September 30, 2025: Test environment release, API and system testing begins
- November 2025: Issuer certificates available, mobile app testing; production environment goes live
- February 1, 2026: FA(3) replaces FA(2), e-invoicing mandatory for large taxpayers (turnover > PLN 200M / ~47M€ in 2024)
- April 1, 2026: Rollout to all other taxpayers (except those listed below)
- January 2027: Deadline for micro-businesses (invoice value < PLN 450 / ~106€ and monthly sales < PLN 10,000 / ~2,364€), POS integration, and mandatory use of KSeF invoice numbers
A grace period will apply until January 2027. during which no sanctions will be imposed for non-compliance with the B2B e-invoicing mandate. With all key specifications now available, companies can (and should!) kick off their implementation.
For more details on e-invoicing in Poland, visit our Country Profile.
