MESSAGING API
SMS API built for speed and scale
Send and receive text messages with our powerful SMS API designed for developers and no-code teams. With rapid set up, reliable delivery and security built in, businesses can send confidently with the Esendex SMS API.
Integrate our API with your existing systems to scale and automate your customer communication, ensuring the right text message is sent at the right time.
Everything you need from an SMS API
Lightning quick
SMS is the fastest way to reach any mobile phone. Use our API for delivery in seconds and a setup process that sees your first message sent on the same day.
Reliable performance
Rest assured that time-sensitive text messages will be delivered securely and on-time, with industry leading performance and built-in compliance, including GDPR and ISO 27001.
Effortless integration
With our quickstart guides and 24/7 professional support, set up and integration into your existing systems is straightforward for developers and no-code teams alike.
> 5bn messages
Each year over five billion messages are delivered through our messaging API by businesses worldwide.
99.9% uptime
Scale your messaging without experiencing dips in performance. Rely on 99.9% uptime for reliability during peak times.
< 2 hours
Most teams send their first live message in under two hours with our straightforward set up, integration and expert support.
Built by developers, for developers. Integrate our SMS API for simple, real-time communication
Use our API documentation to integrate Esendex’ services into your systems within minutes. Here’s how to send an SMS:
// The POST v1/messages endpoint allows you to send a message to a single contact in one request.
// The message can also be sent via different channels; including SMS, Whatsapp and RCS.
curl -X POST 'https://api.esendex.co.uk/v2/messages' -H 'X-Api-Key: {{your-key-here}}' -H 'Content-Type: application/json' -d
{
"accountReference": "EXxxxxxxxx",
"name": "name",
"characterSet": "characterSet",
"channel": "channel",
"from": "from",
"validity": "2025-07-30T09:38:04.4517739+00:00",
"messageType": "messageType",
"body": {
"text": "text",
"templateId": "templateId"
},
"recipients": [
{
"msisdn": "msisdn",
"variables": {},
"metaData": {}
}
],
"addressBook": {
"contacts": [
{
"id": "id"
}
]
},
"metaData": {}
}
No commitment, 30 day free trial
Begin your journey by opening a free Esendex account today and get 100 SMS credits.
Ready? Set? Go!
Learn how to get your service up and running with our simple quickstart guides.
Not a coder? We’ve got you covered
Our managed services team can help you set up and run your SMS API at no extra cost. From initial configuration to testing and live deployment, we’ll make sure everything is in place so you can start sending messages with confidence.
“Our estate agent customers need to send appointment reminders and property transaction updates reliably and on time. With SMS from Esendex, texts land straight into the hands of the agent’s clients when they are most valuable to them.”
Riccardo Dawson – Chief Operating Office, Software at Houseful
Let’s start sending, together.
Discover the full power of our mobile messaging platform.
Why choose Esendex?
Having us in your corner ensures that you can support your customers and your business – whatever comes your way.
20+ years of experience
Industry leading support
An expert and reliable partner
One-on-one with everyone
Flexible and scalable options
Solutions designed for you
Get the most out of SMS with our powerful API
Notifications and alerts
Send instant updates on orders, deliveries, and service changes to keep customers informed.
Two-factor authentication (2FA)
Protect user accounts with secure one-time passcodes sent quickly by SMS.
Marketing campaigns
Deliver personalised promotions and offers directly to your customers’ phones.
Appointment reminders
Reduce missed appointments with clear and timely SMS reminders.
Automate messages
Set up intelligent workflows to automate responses and manage customer journeys by SMS.
Surveys and feedback
Collect valuable insights with quick customer surveys sent by SMS.
FAQs
How do I know if my message has been delivered?
Our API provides real-time delivery receipts so you can track the status of every message you send.
Is the SMS API secure and GDPR compliant?
Yes. Our platform is fully compliant with GDPR and ISO 27001, with encryption in transit and at rest.
What kind of support is available during and after integration?
You’ll have access to 24/7 support from our expert team, plus free setup assistance if you need it.
Can I send messages internationally using the API?
Yes. Our SMS API supports global delivery to over 190 countries with the same reliability and speed.
What programming languages are supported?
We provide clear examples in JavaScript, Python, Java, C#, PHP and cURL in our support docs to help you integrate quickly.
Is there a sandbox or testing environment available?
Yes. You can test and simulate messages safely using our dedicated sandbox environment.
Do I need coding skills to use the API?
No. While developers can integrate directly, no-code teams can use our tools and guided setup.
Are there templates or pre-configured integrations available?
Yes. Our API works with platforms like Salesforce and Zapier, alongside pre-built message templates.