Download Offline Invoice

GET /invoices/{environment}/offline/{id}

Downloads an offline invoice document in the selected format. Unlike online invoices, offline invoices support an additional cert document type for the certificate QR code.

Path Parameters

Parameter	Type	Required	Description
environment	string	✅	test, demo or prod
id	string (uuid)	✅	Offline invoice ID

Query Parameters

Parameter	Type	Default	Description
docType	string	xml	Document format

Allowed docType values

Value	Description
xml	Signed XML (or unsigned if not yet signed)
pdf	PDF with 2 QR codes: invoice QR (KOD I) and certificate QR (KOD II)
qr	Invoice QR code as PNG image (KOD I — OFFLINE)
cert	Certificate QR code as PNG image (KOD II — CERTYFIKAT)

Response 200 — XML

{
  "id": "uuid",
  "invoiceNumber": "FV/2026/01/001",
  "docType": "xml",
  "contentType": "application/xml",
  "content": "PD94bWwg...base64...",
  "fileName": "FV-2026-01-001.xml"
}

Response 200 — PDF

{
  "id": "uuid",
  "invoiceNumber": "FV/2026/01/001",
  "docType": "pdf",
  "contentType": "application/pdf",
  "content": "JVBERi0...base64...",
  "fileName": "FV-2026-01-001.pdf",
  "qrLinkInvoice": "https://qr-test.ksef.mf.gov.pl/invoice/...",
  "qrLinkCertificate": "https://qr-test.ksef.mf.gov.pl/certificate/..."
}

PDF with 2 QR codes

The offline invoice PDF contains two QR codes when available:

• KOD I (invoice QR) — verifies the invoice content hash
• KOD II (certificate QR) — verifies the signing certificate

The PDF also includes an "OFFLINE" watermark to distinguish it from online invoices.

Response 200 — QR / Cert

{
  "id": "uuid",
  "invoiceNumber": "FV/2026/01/001",
  "docType": "qr",
  "contentType": "image/png",
  "content": "iVBORw0...base64...",
  "fileName": "FV-2026-01-001-qr.png",
  "qrVerificationUrl": "https://qr-test.ksef.mf.gov.pl/invoice/..."
}

For docType=cert, the response has the same structure but with "docType": "cert", file suffix -cert-qr.png, and qrVerificationUrl pointing to the certificate verification URL.

Error Codes

Code	Description
400	Invalid docType or missing QR data
401	Unauthorized
404	Offline invoice not found
500	PDF generation error