Send invoice via email

Sends an invoice to the customer via email as a PDF attachment. The invoice must have a contact with a valid email address set.

What happens when you send an invoice:

1. Invoice PDF document is generated
2. Invoice status changes from “New” to “Sent”
3. Sending date (sentAt) is recorded as the current date
4. Sending type is set to “Email” (indicating email sending)
5. Contact recipient is recorded (from invoice contactId)
6. Payment due date (dueDate) is calculated based on:
   • Organization-specific payment terms (invoiceDueDays), or
   • Workspace default payment terms (defaultInvoiceDueDays)
7. Status change timestamp and user are recorded
8. Email is sent to the contact’s email address with PDF attachment
9. The payment term starts running from this point

Important restrictions:

• Only invoices with status “New” or “Sent” can be sent
• Invoices that are “Paid” or “Cancelled” cannot be sent
• The invoice must have a contact with a valid email address
• Use POST /billing/setInvoiceContactId to set the contact if needed

Use cases:

• Send invoice to customer via email
• Automate invoice delivery
• Track invoice sending and payment terms

What is returned:

• Success response confirming the invoice was sent

curl -X POST "https://leadtime.app/api/public/billing/invoices/sendInvoice" \
  -H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
  "id": "123e4567-e89b-12d3-a456-426614174000"
}'

const response = await fetch("https://leadtime.app/api/public/billing/invoices/sendInvoice", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_ACCESS_TOKEN",
    "Content-Type": "application/json"
  },
  body: "{\n  \"id\": \"123e4567-e89b-12d3-a456-426614174000\"\n}"
});

import requests

response = requests.post(
    "https://leadtime.app/api/public/billing/invoices/sendInvoice",
    headers={
        "Authorization": "Bearer YOUR_ACCESS_TOKEN",
        "Content-Type": "application/json"
    },
    data="{\n  \"id\": \"123e4567-e89b-12d3-a456-426614174000\"\n}",
)

{
  "success": true
}