Download the legal or original invoice

When working with invoices, it is important to differentiate between:

• Legal invoice file: the final official file that was delivered (issued invoices) or received (received invoices).
• Original invoice file: the first file received by B2Brouter for that invoice (for issued invoices, this is typically an imported source file; for received invoices, this is the invoice received from the issuer).
• Exporting an invoice to a specific format: B2Brouter generates a document from the invoice data (it may differ from the legal/original file).
• Attachments: additional files linked to the invoice (PDFs, etc.). Attachments are not the invoice itself.

Depending on what you need, you will either:

• Call a direct download endpoint (for example, /invoices/{INVOICE_ID}/as/original), or
• Use a download path returned in the invoice JSON (for example, download_legal_url or attachments[].link).

Prerequisites

• An API key with access to the invoice’s project/account.
• The internal B2Brouter invoice.id (you can obtain it from list endpoints).

Step 1: Get the invoice payload (optional but recommended)

Call Get invoice to retrieve the invoice JSON and locate the relevant fields:

curl --request GET \
  --url https://api-staging.b2brouter.net/invoices/{INVOICE_ID}.json \
  --header 'X-B2B-API-Key: {YOUR_API_KEY}' \
  --header 'X-B2B-API-Version: {YOUR_API_VERSION}' \
  --header 'accept: application/json'

Issued invoices: legal file via download_legal_url (IssuedInvoice / IssuedSelfInvoice)

After an issued invoice is sent, the response can include download_legal_url, which points to the legal file delivered to the receiver (for example, the exact XML submitted to a network/platform, or the legal PDF).

download_legal_url is a relative path (not a full URL), for example:

{
  "invoice": {
    "download_legal_url": "/attachments/download/{ATTACHMENT_ID}/{FILENAME}"
  }
}

Received invoices: original/legal file via /invoices/{id}/as/original

For received invoices, the original file is also the legal file. Download it directly with:

GET /invoices/{INVOICE_ID}/as/original

Attachments (both issued and received): attachments[].link

The invoice JSON can include an attachments array. Each entry contains a link you can use to download the stored attachment.

attachments[].link is a relative path (not a full URL), for example:

{
  "invoice": {
    "attachments": [
      {
        "link": "/attachments/download/{ATTACHMENT_ID}/{FILENAME}",
        "content_type": "application/pdf"
      }
    ]
  }
}

For a deeper explanation of attachments and legal PDFs, see: Manage invoice attachments.

Step 2: Download the file

The URL fields returned by the API (download_legal_url, attachments[].link) are relative paths. Prefix them with your environment base URL.

Download using download_legal_url (issued invoices, legal)

curl --request GET \
  --url "https://api-staging.b2brouter.net{download_legal_url}" \
  --header 'X-B2B-API-Key: {YOUR_API_KEY}' \
  --header 'X-B2B-API-Version: {YOUR_API_VERSION}' \
  --output legal_invoice

Download using attachments[].link (attachments)

curl --request GET \
  --url "https://api-staging.b2brouter.net{attachment_link}" \
  --header 'X-B2B-API-Key: {YOUR_API_KEY}' \
  --header 'X-B2B-API-Version: {YOUR_API_VERSION}' \
  --output attachment_file

Download using /invoices/{id}/as/original (original)

curl --request GET \
  --url "https://api-staging.b2brouter.net/invoices/{INVOICE_ID}/as/original" \
  --header 'X-B2B-API-Key: {YOUR_API_KEY}' \
  --header 'X-B2B-API-Version: {YOUR_API_VERSION}' \
  --output original_invoice

Notes

• For received invoices, /invoices/{INVOICE_ID}/as/original returns the file received from the issuer (original = legal).
• For issued invoices, /invoices/{INVOICE_ID}/as/original only works when the invoice has an original file (for example, imported XML). If the invoice was created directly from a JSON payload, there may be no original file to download.

Related endpoints

• Get invoice
• Get an invoice with a specific document type
• Get received invoice (list)