Bulk messaging

Contacts, phonebooks, campaigns, and batch sends

Bulk traffic uses a dedicated expansion queue so campaigns do not block transactional sends.

Contacts Phonebook Campaign Bulk batch

requestPOST /bulk-sms

{
  "campaignId": "c0ffee00-0001-4000-8000-000000000001",
  "contactListId": "c0ffee00-0002-4000-8000-000000000002",
  "text": "Hello {{FIRST_NAME}}, your offer expires tonight.",
  "scheduledAt": "2026-08-11T09:00:00Z"
}

Phonebook snapshot

Recipients are expanded into trackable messages by the bulk worker.

Schedule or start

Pass scheduledAt, or start later with PATCH …/start.

Per-recipient export

Filter batch messages and download CSV results.