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KSeF / FA3

Krajowy System e-Faktur

What is KSeF?

KSeF (Krajowy System e-Faktur) is Poland's national e-invoicing system. It mandates the issuance, receipt, and storage of invoices through a centralized platform managed by the Polish Ministry of Finance. All B2B invoices will be required to go through this system from 2026.

Mandatory Timeline

DateMilestone
1er février 2026Mandatory for large companies (revenue > 200M PLN)
1er avril 2026Mandatory for all VAT-registered businesses

Source: Polish Ministry of Finance (podatki.gov.pl)

FA3 Format

The FA3 format (Faktura ustrukturyzowana) is the official XML schema used by KSeF. It defines the mandatory structure for electronic invoices in Poland.

Technical Specifications

  • Format: XML compliant with FA(3) schema
  • XSD Schema: available on gov.pl
  • Encoding: UTF-8
  • Max size: 16 MB per invoice

Need help with KSeF?

We support you in achieving compliance: data mapping, XSD validation, demo environment testing.

Disclaimer

The information presented on this page is provided for informational purposes and may change. Always consult official sources for the most up-to-date information.