Invoicing in Poland and KSeF: what a sole trader must do

Since 2026 Poland is moving all business invoices to the national e-invoicing system KSeF (Krajowy System e-Faktur). For a small sole trader the key dates are 1 April 2026 and 1 January 2027.

KSeF dates

• 1 February 2026 – issuing in KSeF mandatory for taxpayers whose 2024 sales (incl. VAT) exceeded 200 million zł; receiving invoices through KSeF mandatory for everyone.
• 1 April 2026 – issuing in KSeF mandatory for all other taxpayers.
• Until 31 December 2026 – you may still issue invoices outside KSeF (paper or electronic) if the total gross value of invoices you would have to issue in KSeF does not exceed 10,000 zł in a month. Once one invoice takes you over that, that invoice and all later ones go through KSeF, even if a later month is lower.
• 1 January 2027 – KSeF mandatory for everyone, including the smallest businesses.

Penalties: the Ministry of Finance announced (16.09.2026) and the Council of Ministers adopted a bill (20.10.2026) deferring penalties for KSeF errors until 31 December 2027. At the time of checking this is a government bill, not yet law. The duty to use KSeF does not change.

Not sent to KSeF: pro forma invoices, internal documents, credit/debit notes (noty). Correction notes (noty korygujące) were abolished from 1 February 2026.

VAT exemption: the 240,000 zł limit

Under art. 113(1) of the VAT Act a business based in Poland is VAT-exempt if its sales (excluding VAT) did not exceed 240,000 zł in the previous or current tax year. Some activities cannot use this exemption regardless of turnover – they are listed in art. 113(13) (for example certain goods and some services such as legal and advisory services). Being VAT-exempt does not free you from KSeF for invoices you issue to businesses.

What an invoice must contain

In KSeF the structured invoice format (FA) enforces the required fields – seller and buyer data with NIP, date, numbering, description, net amounts, VAT rate or exemption basis. The Ministry of Finance provides free tools for issuing invoices in KSeF (listed on ksef.podatki.gov.pl); commercial invoicing software connects through the KSeF API.

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