Poland National E-Invoicing (KSeF) Compliance and Archiving Requirements
Poland’s National e-Invoicing System (KSeF) has been mandatory for public procurement (B2G) since 2019 and will be rolled out for all business-to-business (B2B) transactions in phases from February 2026. Every Polish taxpayer must issue, submit and retrieve legally valid e-invoices via KSeF, following specific formats, deadlines and archiving rules.