KSeF
Guides
Simple explanations of KSeF and invoicing in Poland. We write them for people who run a JDG.
KSeF explained for foreigners running a JDG
This guide explains what KSeF is, who must use it, and what changes if you run a sole proprietorship (JDG) in Poland and invoice in English.
KSeF deadlines 2026-2027 and what they mean for a JDG
This guide gives a clear timeline of the KSeF dates from 2026 to 2027. It explains what each date means for a sole proprietorship in Poland.
How to get a KSeF certificate
This guide gives a high-level procedure to log in to the official KSeF app, generate an authentication certificate, and keep the key file and password safe.
Invoicing foreign clients from Poland
This guide explains currency, the NBP exchange rate, reverse charge wording, VIES checks and bilingual invoices for a JDG with clients abroad.