KSeF
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Poland's centralised clearance, modelled on Italy's SdI.
Definition
KSeF receives the invoice in the FA XML schema, checks its conformity and assigns a timestamped KSeF identification number that sets the legal issuance date. The invoice is then made available to the buyer through the system.
The system is reachable by API; authentication can use the Profil Zaufany or a certificate, among others. Voluntary since January 2022, KSeF has been mandatory since 1 February 2026 for the largest companies and since 1 April 2026 for other taxpayers, after the original 1 July 2024 deadline was postponed; some small taxpayers have until 1 January 2027. Since February 2026 invoices follow the FA(3) structure, which replaced FA(2).
Origin
Established by Poland's VAT Act (ustawa o VAT) and operated by the Ministry of Finance / Krajowa Administracja Skarbowa; FA structures published as official XSD schemas.
Example in context
After submitting the FA(3) XML, KSeF returns an Urzędowe Poświadczenie Odbioru (UPO) containing the invoice's KSeF number.
Related terms
- SdI — Italian equivalent.
- Clearance model — KSeF is centralised.