Queue an SMS to go out at a specific future time or date — appointment reminders, drip campaigns, delayed notifications. One extra field on the same send request, billed only when it actually sends, cancel anytime before then.
# Same SMS send request - just add send_at curl -X POST https://app.6xcom.com/api/sms/send \ -H "X-API-Key: YOUR_API_TOKEN" \ -H "Content-Type: application/json" \ -d '{"to":"+15551234567","from":"6XBusiness","message":"Reminder: your appointment is at 2pm today.","send_at":"2026-09-10T09:00:00Z"}'
Full reference, error codes, and the cancel/list endpoints: SMS Send API docs →
Book something today, remind the customer the morning of — no manual follow-up needed.
Queue a sequence of messages spaced out over days or weeks, set once and forget.
Trigger a message now, deliver it at a better time for the recipient's timezone or schedule.
No separate scheduling system to learn - add send_at to the SMS send request you already use.
Nothing is charged when you schedule a message - only when it actually goes out.
List every pending scheduled message and cancel any of them before their send time.
Combine scheduling with a bulk send for a whole campaign that goes out exactly when you want.
Add one extra field, send_at, to the same SMS send request you'd normally use — the message queues instead of sending immediately and goes out automatically at that time.
At actual send time, not when you schedule it — if you cancel before it sends, you're never charged for it.
Yes — any message still pending can be cancelled before its scheduled send time, and you can list all your pending scheduled messages at any time.
Any future date and time — the message queues and sends automatically on schedule, checked every minute.
Bulk SMS sends a batch to many recipients right away; Scheduled SMS delays when a message (single or as part of a batch) actually goes out — the two work together, not as alternatives.
Scheduling itself has no extra fee — you pay the normal per-message SMS rate at the moment it actually sends, same as any other message on your account.
Register free, and start scheduling messages with the same SMS API you'd use to send right now.
Need to know when it's delivered? Pair scheduled sends with Webhooks to get a real-time push the moment each message lands.
Webhooks →