Poland’s Ministry of Finance Launches the KSeF 2.0 API Test Environment
On 30 September 2025, Poland’s Ministry of Finance launched the test (integration) environment for the KSeF 2.0 API. The open testing phase is designed to enable financial and accounting software providers to verify how their systems interact with the National e-Invoice System (KSeF) and to ensure readiness for the upcoming mandatory use of the system.
Technical Support and the KSeF 2.0 Manual
Entities using the test environment can obtain technical support via an online application form. The technical support team is available on business days between 7:00 a.m. and 7:00 p.m.
In addition, the Ministry of Finance has published the KSeF 2.0 Manual – a four-part comprehensive document explaining the key principles and functionalities of the National e-Invoice System. The manual includes:
- Part I – general information about the system, including key implementation dates, authentication methods, and the access rights model
- Part II – processes for issuing, receiving, and accessing e-Invoices, assigning KSeF numbers, and guidelines for correctly completing the FA(3) structure
- Part III – additional functionalities, such as sending invoices with attachments, operating in offline mode, handling VAT RR invoices, self-billing, and reporting scam invoices
- Part IV – invoicing rules applicable to local government units and VAT groups, as well as invoicing within enforcement and public procurement procedures
The manual is available on the KSeF website.
Next Steps in the KSeF 2.0 Rollout
- 15 October 2025 – Launch of the pre-production (DEMO) environment
- 1 November 2025 – Launch of the Certificates and Authorizations Module (MCU), enabling users to apply for system certificates
- 15 November 2025 – Release of the test and pre-production (DEMO) versions of the KSeF 2.0 Taxpayer Application
- 1 January 2026 – Activation of the notification module for invoices with attachments in the e-US system (electronic tax office platform)
- 1 February 2026 – Launch of the production version of the KSeF 2.0 system
There’s more you should know about e-invoicing in Poland – learn more about the new and upcoming regulations.
