Poland is entering a new era of digital compliance. Starting in 2026, e-invoicing via the National e-Invoicing System (KSeF) will become mandatory for B2B transactions, fundamentally changing how businesses operate and report VAT.
This shift is not just about compliance; it’s about future-proofing your business for a digital-first economy.
Key facts at a glance:
Mandate timeline
- February 2026: Mandatory for taxpayers with turnover above PLN 200M (EUR 46M).
- April 2026: Mandatory for all remaining taxpayers.
- Scope: Applies to all B2B invoices under Polish VAT law, including corrective and advance invoices. B2C, and certain document types (like railway tickets), are excluded from the mandate.
- Model: Clearance model—suppliers must send invoices to KSeF for validation and clearance.
- Archiving: Both suppliers and buyers must archive invoices for at least five years; KSeF stores them for 10 years. As always with archiving, there are exceptions that require longer storage time.
Supplier checklist: Are you ready?
- Register with KSeF: Ensure your legal entities are registered on the KSeF platform.
- Be ready for a manual process or obtain API credentials: Acquire your KSeF API key and provide it to your e-invoicing provider (e.g., Basware).
- Prepare invoice data: Ensure all invoice data meets the FA_VAT 3 format and Polish content requirements.
- Work with KSeF: Use a compliant solution (like Basware) to automatically convert and transmit invoices for clearance or do it manually if your invoice volume is low.
- Archive properly: Set up processes to archive invoices for at least five years outside KSeF if needed (for example, for documents not processed by KSeF).
- Self-billing: If applicable, establish formal agreements and KSeF authorizations for self-billing scenarios.
- Consider delivery methods: Your buyer should pick up the cleared invoice directly from the KSeF portal but may request that you send additional data through an alternative channel.
Buyer checklist: What should you do?
- Connect to KSeF: Be ready to check for and retrieve cleared invoices directly from the platform.
- Verify clearance: If receiving invoices outside KSeF, always check for clearance evidence. The KSeF-assigned number must be present on the document.
- Process and archive: Ensure your AP process can handle cleared e-invoices and archive them as required.
- Communicate requirements: If you need invoices delivered outside KSeF, provide correct endpoint addresses to suppliers. A reason for this could be that you require more data than KSeF is able to transmit.
Why this matters
The Polish e-invoicing mandate is more than a regulatory hurdle—it’s a catalyst for digital transformation. Businesses have the potential to benefit from streamlined processes, reduced fraud risk, and improved VAT compliance. By leveraging advanced solutions like Basware, organizations can turn compliance into a competitive advantage, ensuring resilience and agility in a rapidly evolving market.
The future of invoicing is digital, compliant, and connected. Are you ready to lead? Download our Buyer’s Guide to Invoice Compliance Solutions to explore evaluation criteria, key questions, and strategies for compliance success.
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