After the National E-Invoicing System (“KSeF”) takes effect, businesses will have to make sure their JP_VAT files contain KSeF identification numbers for invoices, called KSeF IDs. A relevant regulation by the Minister for Finance and Economy which imposes such duty was sent for promulgation yesterday (Regulation of 12 December 2025 to amend the regulation amending the regulation on details to be disclosed in goods and services tax returns and records) and will enter into force one day after the promulgation date.

In accordance with the regulation, as of February 2026, when submitting their JPK_VAT file:

  • a supplier required to use KSeF to issue invoices will have to make sure their JPK_VAT file contains the KSeF identification number (KSeF ID) for each of its sales invoices;
  • if the supplier is unable to state the KSeF ID at the time of JPK_VAT submission, it will have to ensure the file contains the following codes, as appropriate:
  • OFF – where the invoice was issued under the KSeF malfunction procedure (no KSeF ID and failure of invoice submission to KSeF);
  • BFK – where the invoice is not a structured invoice in accordance with the law (e.g. it is a VAT invoice issued by a VAT-registered entity whish has not established its business and has no fixed establishment in Poland or by a small business that is not required to start issuing structured invoices until April 2026 but will use BFK code for its sales in JPK submission for February);
  • DI – for sales evidence other than an invoice (e.g. charge of output tax on employee compensation or benefits) and for invoices issued in the offline24 process which still do not have their KSeF IDs at the time of JPK-VAT submission).

Where the JPK submission shows DI code for an invoice issued offline, you will have to file amended JPK_VAT with the KSeF ID for the invoice once you obtain that number.

  • The customer will have to make sure its purchase records contain the KSeF IDs for purchase invoices even if it is not yet required to use KSeF IDs as supplier for its sales invoices until 1 April 2026.

Those changes require modifications in the schema of JPK_VAT with declaration disclosures.

If this issue pertains to your business and you are interested in our assistance, please contact us.

This blog post is provided for general information purposes to keep you up-to-date with changes in tax law, tax rulings by authorities, case law of courts and interesting commentaries. Doradztwo Podatkowe WTS&SAJA shall not be held legally liable for any acts or omissions resulting from reliance on such information.