B2G invoices in PEF: submission to KSeF and assignment of a number

This guide is for sole traders who issue B2G (Business to Government) invoices through PEF. It covers only the connection between such invoices and KSeF, not how to determine whether using either system is mandatory.

Previously, PEF and optional KSeF operated separately

The Ministry of Finance explains that PEF and the optional version of KSeF operated as separate systems. This describes the earlier model, which the Ministry distinguishes from the rules for B2G invoices during the mandatory KSeF period. Source: Ministry of Finance — “Scope of mandatory KSeF”, section “KSeF and PEF” (in Polish).

Two conditions for an invoice issued in PEF

According to the Ministry’s explanation, during the mandatory KSeF period, a B2G invoice issued in PEF is recognised as a structured invoice once both conditions have been met:

• it has been submitted to KSeF;
• it has been assigned a KSeF number.

Creating the document in PEF alone therefore does not mean that these two conditions have been met. Issuing an invoice in PEF should not be equated with submitting it to KSeF and having a number assigned. This distinction follows from the Ministry’s explanation concerning KSeF and PEF (in Polish).

Making the invoice available to the counterparty

The Ministry also links making the invoice available to the counterparty to these same conditions: B2G invoices issued in PEF are made available to the counterparty after submission to KSeF and assignment of a KSeF number. This is how the process is described in the “KSeF and PEF” section on the Ministry’s website (in Polish).

Optional organisational checklist for sole traders

As an organisational aid, we suggest establishing separately:

• Has the invoice issued in PEF been submitted to KSeF?
• Has it been assigned a KSeF number?

This is an optional recommendation for organising information, not an additional legal obligation or technical instructions for checking the document.