# 📦 Download invoice as UBL 2.1 XML Download an invoice as UBL 2.1 XML (Peppol BIS 3.0 compliant). Returns the invoice as a UBL 2.1 XML document that can be used for e-invoicing via Peppol network or other UBL-compatible systems. Args: invoice_id: The invoice ID (or draft_id) to export Returns: UBL 2.1 XML document with application/xml content type Endpoint: GET /invoicing/invoices/{invoice_id}/ubl Version: 1.0.0 Security: APIKeyHeader ## Path parameters: - `invoice_id` (string, required) ## Header parameters: - `X-PDP-Client-Id` (string, required) ID of the PDP Client for which the operation is performed ## Response 401 fields (application/json): - `error` (string, required) - `code` (integer, required) - `trace_id` (string, required) ## Response 200 fields ## Response 404 fields ## Response 422 fields