---
search:
  tags:
    - billing
    - POST
seo:
  description: >-
    Sends an invoice to the customer via email as a PDF attachment.… Reference
    for the POST /billing/invoices/sendInvoice endpoint in the Leadtime Public
    API API.
sidebar:
  badge: POST
  label: Send invoice via email
title: Send invoice via email
type: openapi-operation
---
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

<Operation source="api-reference" id="invoicescontroller-sendinvoice" />