SMS API

Stable

SMS API

Send transactional and marketing SMS messages to any mobile number. From single alerts to bulk campaigns — with automatic formatting, segmentation, and real-time delivery receipts.

Global Delivery

Reach any mobile number worldwide with intelligent routing across multiple carrier networks.

Instant Dispatch

Sub-second message queuing with typical delivery under 5 seconds for Ghana networks.

Sender ID Verified

Only pre-approved alphanumeric sender IDs are accepted — preventing spam and protecting your brand.

Delivery Tracking

Real-time delivery receipts with provider-level feedback and per-message status tracking.

Bulk Messaging

Send to thousands of recipients in one request with automatic batching and rate management.

Smart Segmentation

Messages over 160 characters are automatically split and concatenated on the recipient's device.

Avg Delivery

<5s

On Ghana networks

Max Length

1530

characters (10 segments)

Rate Limit

100/s

per API key

Bulk Limit

10,000

recipients per request

Authentication

All requests require HTTP Basic Auth using your pre-computed Base64 token from the dashboard. See Authentication →

Quick Start

Send your first SMS in under a minute:

Bash

curl -X POST 'https://api.sendexa.co/v1/sms/send' \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Basic YOUR_DASHBOARD_BASE64_TOKEN' \
  -d '{
    "to": "0244123456",
    "from": "MyBrand",
    "message": "Hello from Sendexa! Your order #1234 is confirmed."
  }'

Response

JSON

{
  "success": true,
  "message": "SMS sent successfully",
  "data": {
    "messageId": "exa_sms_1a2b3c4d5e6f",
    "status": "queued",
    "to": "233244123456",
    "from": "MyBrand",
    "segments": 1,
    "cost": 1
  }
}

API Endpoints

POST

/v1/sms/send

Send Message

Send a single SMS to one recipient with full delivery tracking.

Send the same or personalised messages to multiple recipients in one call.

Poll the delivery status of any message using its message ID.

Retry delivery of a failed or undelivered message without rebuilding the payload.

View docs

Message Types

Transactional

Order confirmations, delivery alerts, account notifications, and security codes triggered by user actions.

Marketing

Promotional campaigns, offers, event reminders, and bulk announcements sent to opted-in subscriber lists.

Scheduled

Messages queued for future delivery at a specific ISO 8601 timestamp — ideal for reminders and campaigns.

Sender ID Requirements

Must be 3–11 characters, letters and numbers only (no spaces or symbols)
Must be pre-approved in the dashboard before use
Unapproved or pending sender IDs will be rejected with a 403 error

Delivery Statuses

Status	Meaning	Action
queued	Message accepted, waiting to be sent to carrier	Wait — normal
sent	Handed off to the carrier network	Wait for delivery receipt
delivered	Confirmed delivered to the handset	Success — store the receipt
failed	Carrier rejected or number unreachable	Check error code, consider resend
expired	Message not delivered within validity period	Use /resend endpoint

Common Error Codes

HTTP	Code	Cause
400	`INVALID_PHONE`	Phone number format not recognised
400	`MESSAGE_TOO_LONG`	Message exceeds 1530 characters (10 segments)
401	`UNAUTHORIZED`	Missing or invalid Authorization header
403	`SENDER_ID_NOT_APPROVED`	Sender ID pending approval or rejected
403	`INSUFFICIENT_CREDITS`	Account balance too low to send
429	`RATE_LIMIT_EXCEEDED`	Exceeded 100 req/s — implement exponential backoff

Best Practices

Store the messageId from every response to enable status checks and resends
Use webhooks for delivery receipts instead of polling the status endpoint
Validate phone numbers client-side before hitting the API to save credits
For bulk sends, use POST /v1/sms/bulk — not repeated single sends
Implement exponential backoff when you receive a 429 response
Keep messages under 160 characters when possible to use a single SMS credit