The Polish KSeF System uses a specific inhouse invoice format based on XML, which is called e-invoice FA. The currently supported version is FA(2). A new version, FA(3), is planned to be released in June 2025.

Mandate information

The Polish government introduced the National e-Invoicing System (KSeF) to facilitate electronic invoicing and ensure real-time reporting of transactions. The e-Invoicing model approach that Poland chose is a centralized model.

KSeF will act as a centralized portal for both sending and receiving electronic invoices.

Timeline

February 1, 2026: Mandatory adoption for large taxpayers (annual turnover exceeding PLN 200 million).
April 1, 2026: Full implementation for all remaining taxpayers.

The KSeF Platform

While e-invoices must be transmitted via KSeF, recipients must consent to receive them in this format. If consent is not granted, the issuer is still required to submit the invoice to KSeF but must also deliver a copy through an alternative method, such as email (PDF) or a printed document via regular mail.

The platform follows a credential-based model, meaning only registered users with authorization can access the system. Once authenticated, users can view, issue, receive, and download invoices in a structured format. Taxpayers have the option to grant third-party access, allowing authorized representatives to manage invoices on their behalf.

Businesses can either create invoices directly within the KSeF platform using predefined templates or generate them within their own ERP/accounting system before submitting them to KSeF. The latter option follows standard automatic process that receive data/map/validate/communicate with KSeF.

Once submitted, the invoice undergoes automatic validation and a unique KSeF ID number is assigned to every invoice, confirming its authenticity.

All invoices processed through KSeF are archived for 10 years, allowing businesses to retrieve them as needed. The platform provides a secure and centralized repository for this archiving functionality.

Details

Detail	Value
Official Specification	KSeF Download and KSeF Guthub
Coverage	B2B
Country-Specific Configuration	Poland B2B: Configuration Overview
Country-Specific Extensions	None

In this section

Topic	Description
Poland B2B: Overview	Get an overview of the requirements for Poland B2B.
Poland B2B: Receiver	View the Receiver used for Poland B2B.
Poland B2B: Example Documents	View some example Documents for Poland B2B.
Poland B2B: Configuration Overview	Get an overview of the configurations for Poland B2B.
Poland B2B: Rules	Read about the Rules used by Poland.