E-invoicing in Poland: KSeF, FA(3) format, mandate 2026
Poland is rolling out e-invoicing through its national KSeF system: large companies from 1 February 2026, all others from 1 April 2026. The thing to know first: the Polish format is called FA(3) and is a national XML of its own, not the EN 16931 syntax from the Peppol world. KSeF works on a clearance model, the invoice is cleared centrally before it counts.
KSeF mandate: large companies (turnover above PLN 200 million, 2024) from 1.2.2026, all other VAT businesses from 1.4.2026, micro businesses and penalties from 1.1.2027. 2026 without fines. Format: FA(3), a national XML through the central KSeF platform, not EN 16931 / Peppol. Vera produces EN 16931 invoices for the EU standard and cross-border cases, but no FA(3) and no KSeF submission.
When does e-invoicing become mandatory in Poland?
The law was signed in September 2025. The mandate is staggered by size and runs through KSeF (Krajowy System e-Faktur), the system of the Ministry of Finance.
| Date | Obligation | Who |
|---|---|---|
| 1 Feb 2026 | Issue through KSeF | Large companies, turnover above PLN 200 million (2024) |
| 1 Apr 2026 | Issue through KSeF | All other VAT-registered businesses |
| 1 Jan 2027 | Micro businesses plus penalties | remaining groups, strict enforcement |
FA(3) and KSeF vs EN 16931
The Polish format is FA(3), a structured XML that replaces the older FA(2) schema from January 2026. Submission runs centrally through KSeF, which validates and clears the invoice. FA(3) is a national format and not the EN 16931 syntax UBL or CII used by Peppol BIS and XRechnung.
What Vera does for Poland, and what it does not
Vera makes sense for Poland where the EU standard counts: cross-border B2B invoices to EN 16931 and preparing for the ViDA reporting requirements from 2030. The purely Polish domestic case through KSeF is covered by a national provider.
FAQ
When does e-invoicing become mandatory in Poland?
Large companies (turnover above PLN 200 million, 2024) from 1.2.2026, all other VAT businesses from 1.4.2026, micro businesses plus penalties from 1.1.2027. 2026 is a transition period without fines.
Which format does Poland use?
The national FA(3) format, which replaces the FA(2) schema from January 2026, submitted through KSeF. FA(3) is not identical to EN 16931 or Peppol BIS.
What is KSeF?
KSeF (Krajowy System e-Faktur) is Poland's national e-invoicing system. Invoices are uploaded centrally, validated and cleared. B2B and B2G run through it.
Can I produce a KSeF invoice in the FA(3) format with Vera?
No. Vera produces e-invoices to EN 16931. FA(3) and KSeF submission are a separate national system Vera does not serve. For that you need a solution connected to KSeF.
Are there already penalties in Poland in 2026?
No. 2026 is a transition period without financial penalties. Strict enforcement starts on 1 January 2027.
EN 16931 invoices for the EU standard
For cross-border B2B invoices to EN 16931, Vera produces XRechnung, Factur-X and Peppol BIS in the browser, validated before download. The Polish domestic case through KSeF is covered by a national provider.
Create one nowFree for 5 invoices / month · Pro 29 € / month · 27 EU countries