Send invoices and documents on WhatsApp

Invoices sent by email are often filtered, and paper copies are easily lost. A PDF in a WhatsApp conversation is easy to find again and to forward, and the customer can ask a question in the same thread.

Common documents

• Invoices and receipts after a purchase or payment
• Tickets and boarding passes for events and travel
• Statements for accounts, subscriptions and utilities
• Reports and certificates, such as service reports and course certificates
• Quotations and contracts for review and approval

Example template

A template with a document header can be sent at any time, including to customers who have not messaged you recently:

[PDF: Invoice INV-2291.pdf] Hi {{1}}, please find attached invoice {{2}} for {{3}}. Payment is due by {{4}}. Reply to this message with any questions. [ Pay now ]

“Pay now” is a URL button that opens your payment page.

Sending documents automatically

curl -X POST "$HELLO_API_URL/v1/<your-phone-number-id>/messages" \
  -H "Authorization: Bearer $HELLO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to": "+61412345678",
    "type": "template",
    "template": {
      "name": "invoice_ready",
      "language": { "code": "en" },
      "components": [
        { "type": "header", "parameters": [
          { "type": "document", "document": {
              "link": "https://example.com/invoices/INV-2291.pdf",
              "filename": "Invoice INV-2291.pdf" } } ] },
        { "type": "body", "parameters": [
          { "type": "text", "text": "Alex" },
          { "type": "text", "text": "INV-2291" },
          { "type": "text", "text": "$420.00" },
          { "type": "text", "text": "15 October" } ] }
      ]
    }
  }'

Within an open 24-hour window, for example when the customer has just asked for a copy, you can send the file as a plain document message without a template.

Private files

If documents should not be available at a public URL, upload the file to Hello first and send its media_id instead of a link. A media ID remains valid for about 30 days.

Recommendations

• Use descriptive file names, such as “Invoice INV-2291.pdf” rather than “doc_88213.pdf”.
• Include the key details in the message text, such as the amount and due date, so customers do not need to open the file.
• Keep document messages transactional. Send promotions separately as marketing messages.
• Check delivery status. Hello shows whether each message was delivered, read or failed.