From 1st April 2026, Poland will begin rolling out mandatory e-invoicing through the National e-Invoicing System (KSeF). This marks a major shift in how invoices are issued, received, and validated.
Here are the key points for self-employed professionals, contractors, and companies:
Invoices must be issued through KSeF
Invoices will need to be submitted to the government platform first. Once validated, the system assigns a unique invoice number and timestamp.
Structured invoices replace PDFs
Invoices must follow a structured XML format. PDFs can still be shared with clients as a visual copy, but they are no longer the official invoice.
Most VAT-registered businesses are affected
This includes freelancers, sole traders, SMEs, and foreign companies registered for VAT in Poland.
Invoices are legally issued only after system approval
An invoice is considered issued once it is accepted by KSeF not when it is sent to the client.
Why this matters:
Companies and contractors invoicing from Poland will need accounting systems capable of integrating with the KSeF platform.
For many freelancers and international contractors, this means updating invoicing tools or workflows before April 2026.
