KSeF (National e-Invoicing System)

That KSeF (National e-Invoicing System) is Poland’s national e-invoicing system: a central government platform through which, according to the contribution (as of November 2025), the exchange of B2B invoices is exclusively taking place. The KSeF operates as a clearance system with real-time verification of each transaction.

Schedule and start

According to the article (as of November 2025), the obligation applies from 01.02.2026 to large taxpayers with a turnover of more than PLN 200 million and from 01.04.2026 to all other taxpayers. According to a source familiar with the matter, the system processed more than 50,000 invoices in the first few days after the launch on February 1. Initially, the influx overloaded the authentication service (Trusted Profile), which the operators quickly resolved. The source concludes that real-time clearance models make operational problems immediately visible.

Format and archiving

According to the article, Poland uses a single national XML format: e-Faktura. According to the article, the KSeF is responsible for the legal archiving of invoices for 10 years.

In the SAP Business One context

In SAP Business One, the KSeF requirements concern the Polish legal formats (JPK). A new XSD schema for KSeF Invoicing introduces new mandatory markings. The marking NrKSeF carries the KSeF number with 35 characters. Additional markings identify documents on paper or without KSeF (BFK), non-invoice documents (DI), and KSeF downtime (OFF). Only one of these markings is allowed per document. The updated mapping requires SAP Business One 10.0 FP 2602 or later (as of 2026). SAP documents the connection, among other things, in SAP Note 3688380 (PL_KSeF API 2.0). For clearance platforms such as KSeF, Versino recommends SAP BTP Document and Reporting Compliance as an integration layer.

Demarcation

The KSeF is a platform, not an invoice format. According to the post, the format is called e-Faktura. A comparable central platform is the Sistema di Interscambio (SdI) in Italy. See also the Clearance Model (E-Invoice).

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