Bulk send

Send the same message to many numbers in one request.

Use bulk send when the text is identical for every recipient. Pass an array of E.164 phone numbers and one message body. Each number is queued and billed independently.

POST/api/v1/messages/bulk

Parameters

sender_idstringrequired: Sender ID UUID
phonesstring[]required: Array of E.164 phone numbers (max 10 000 per request)
messagestringrequired: SMS text sent to all numbers

curl -X POST "https://bulksmsapi.inline.co.ke/api/v1/messages/bulk" \
  -H "Authorization: Bearer YOUR_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
  "sender_id": "sid-uuid",
  "phones": [
    "+254712345678",
    "+254723456789"
  ],
  "message": "Flash sale ends tonight! Visit acme.ke"
}'

Response

200: OK

{
  "success": true,
  "data": {
    "queued": 2,
    "parts": 2,
    "created_at": "2026-05-11T09:00:00Z"
  }
}

Sending to contact groups?

For large sends to saved audiences, use campaigns instead, they target contact groups and give you a cost estimate before dispatch.