B2B E-Invoicing to Become Mandatory Starting February 2026

Mandatory B2B E-Invoicing Starts in 2026: Poland’s KSeF system becomes mandatory for large taxpayers from February 1, 2026, and for all others from April 1, 2026, aiming to digitize invoicing and improve VAT compliance.
KSeF Platform Functionality: KSeF validates, stores, and assigns IDs to structured XML invoices, supports both real-time and offline issuance, and serves as a 10-year archive, enhancing transparency and tax audit readiness.
Incentives and Exemptions Introduced: To encourage adoption, VAT refund times are reduced to 40 days, and JPK_FA reporting may be waived. Offline issuance remains optional until end-2026; B2C invoicing via KSeF is voluntary.
Updated Technical Framework and Timeline: KSeF 2.0 updates include a new FA(3) schema, revised API, and integration testing starting September 30, 2025. A new regulation will replace the 2021 framework with modern features like QR codes.
Grace Period for Penalties: No penalties will apply for invoice-related errors until December 31, 2026. Mandatory use of KSeF invoice numbers in payments is postponed until January 1, 2027, with no fines before July 31, 2026.

E-invoicing