E-Invoicing via KSeF - Comply with Poland's Electronic Invoice Mandate

Poland KSeF 2.0 Manual Update 2026

Poland's KSeF 2.0 Manuals have been updated ahead of the 2026 mandatory e-invoicing rollout, strengthening compliance and governance rules. Changes include aligned exclusions under final regulations, API-only certificate applications, clearer VAT and double-invoice guidance, updated verification data, and formal attachment procedures. Businesses should review ERP integration and KSeF compliance before 2026.

Mandatory Notifications for Invoice Attachments in Poland's KSeF 2.0

businesses must notify the tax authority before sending invoices with attachments in KSeF 2.0. Approval via e-Urząd Skarbowy is required (up to 3 business days). Only tax-related data is allowed in attachments. Companies must ensure ERP integration and KSeF API compliance to avoid disruptions before the 2026 mandate.

KSeF Poland Exemptions

Poland's KSeF system requires domestic B2B invoices to be issued in structured FA (3) XML format. Limited exemptions apply, including certain transport, toll, financial, and foreign self-billing cases. Exempt invoices are valid but not submitted to KSeF and receive no KSeF ID. Businesses must correctly classify transactions and ensure proper ERP integration for full 2026 compliance.

Official draft of FA3 data schema Published

Poland is advancing digital tax administration with the National e-Invoicing System (KSeF), which will soon mandate e-invoicing for all businesses. Central to this initiative is the FA3 data schema, a new standardized XML format designed to replace the current FA2 schema. The FA3 schema aims to enhance transparency, reduce tax fraud, and streamline business transactions by ensuring all e-invoices.

Release of KSeF 2.0 API Documentation and Other Guidelines

On June 30, 2025, the Polish Ministry of Finance (MoF) released KSeF 2.0 API documentation, along with supplementary guidelines detailing the use of QR codes, offline mode operations, and KSeF certificates.

The update includes:

KSeF 2.0 API Documentation: The API documents will help service provider to prepare for the API testing on KSeF 2.0 test environment which will be available from September 30, 2025.

Offline Mode: To issue the invoice outside KSeF and later sending it to the system before a deadline. There are four types of offline mode- Offline24, offline, failure and total failure mode.