The final schema FA_VAT (3), developed after multiple public consultations with businesses, will replace the currently applicable version FA_VAT (2) and enter into force on February 1, 2026.
The new API documentation enables integrators to prepare for testing in the KSeF 2.0 TEST environment, which will be available from September 30, 2025. The released materials include:
- API specification in OpenAPI 3.0.4 (JSON) format
- Interactive documentation listing endpoints, parameters, schem…