curl --request POST \
  --url https://{your-subdomain}.neetoinvoice.com/api/external/v2/clients/{client_id}/invoices/{invoice_id}/send \
  --header 'Content-Type: application/json' \
  --header 'X-Api-Key: <x-api-key>' \
  --data '
{
  "recipient_ids": [
    "128c1dfc-b29f-4fda-9a05-8a90e197b81b"
  ],
  "subject": "Invoice INV-2026-042 from Your Company",
  "message": "Please find attached your invoice for the services rendered.",
  "attach_pdf_invoice": true,
  "send_me_a_copy": false,
  "email": "oliver@example.com"
}
'

const options = {
  method: 'POST',
  headers: {'X-Api-Key': '<x-api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    recipient_ids: ['128c1dfc-b29f-4fda-9a05-8a90e197b81b'],
    subject: 'Invoice INV-2026-042 from Your Company',
    message: 'Please find attached your invoice for the services rendered.',
    attach_pdf_invoice: true,
    send_me_a_copy: false,
    email: 'oliver@example.com'
  })
};

fetch('https://{your-subdomain}.neetoinvoice.com/api/external/v2/clients/{client_id}/invoices/{invoice_id}/send', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://{your-subdomain}.neetoinvoice.com/api/external/v2/clients/{client_id}/invoices/{invoice_id}/send"

payload = {
    "recipient_ids": ["128c1dfc-b29f-4fda-9a05-8a90e197b81b"],
    "subject": "Invoice INV-2026-042 from Your Company",
    "message": "Please find attached your invoice for the services rendered.",
    "attach_pdf_invoice": True,
    "send_me_a_copy": False,
    "email": "oliver@example.com"
}
headers = {
    "X-Api-Key": "<x-api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

{
  "message": "Invoice 'INV-2026-042' emailed to billing@acme.example.com and ap@acme.example.com.",
  "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "number": "INV-2026-042",
  "sent_date": "2026-10-15",
  "recipient_emails": [
    "billing@acme.example.com",
    "ap@acme.example.com"
  ]
}