Poland prepares for Mandatory B2B E-Invoicing with new KSeF Tools- Certificates and Authorizations Module (MCU)

Starting February 1, 2026, Poland mandates B2B invoicing via the National e-Invoice System (KSeF). To support this, the Ministry of Finance released key tools, including the MCU for managing access and digital certificates, which are essential for KSeF 2.0 access.

Starting February 1, 2026, Poland will require businesses to use the National e-Invoice System (KSeF) for B2B invoicing. To help companies get ready, the Ministry of Finance has launched key tools and updates. As a reminder, in the middle of October 2025, a demo version of the KSeF 2.0 API was released, allowing businesses to test their financial systems with real authentication methods. November 1, 2025: The Ministry launched the Certificates and Authorizations Module (MCU), a tool for managing access to KSeF.

The MCU lets users:

• Manage system permissions
• Apply for digital certificates
• Download issued certificates

These certificates act as electronic proof of identity and contain sensitive company or personal data. They will be required to access KSeF 2.0 starting February 2026. New authorizations can no longer be granted through the old KSeF 1.0 Taxpayer Application.All new permissions must be managed through the MCU.