KSeF FA(3) e-invoice API for Poland

FA(3) XML

KSeF FA(3) e-invoice API for Poland

Polish National e-Invoice System (KSeF) structured invoices in the FA schema. Generate and validate payloads ready for Krajowy System e-Faktur submission.

Legal compliance dates

Poland · KSeF 2.0
Structured FA invoices for B2B through the Ministry of Finance gateway
EU · EN 16931
Map from Peppol / UBL / CII into the national FA schema
Cross-border · Optional
Use convert endpoints when the buyer is outside KSeF

Sample JSON payload

{
  "invoice": {
    "number": "FA/2026/0042",
    "issueDate": "2026-09-04",
    "currency": "PLN",
    "seller": { "name": "codecafe24 Sp. z o.o.", "nip": "5252345678" },
    "buyer": { "name": "Acme Polska", "nip": "1132456789" }
  }
}