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.

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SMS API

Trusted by 46,000 customers to deliver world class mobile messaging services

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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, setting up and integrating into your existing systems is straightforward for developers and no-code teams alike.

Built by developers, for developers. Integrate our APIs 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.

{
    "accountReference" : "EXUK0000",
    "name": "name",
    "characterSet": "GSM",
    "channel": "SMS",
    "from": "71460491",
    "validity": "2025-07-19T09:07:12.190Z",
    "messageType": "MarketingAndResearch",
    "body": {
        "text": "example",
        "templateId": ""
    },
    "recipients": [
        {
            "msisdn": "+4470000000000",
            "variables": {
            },
            "metaData": {
            }
        }
    ],
    "metaData": {
        "zsuvhhn": "niqloaf",
        "xljgmvj": "akwenax"
    }
 }
No commitment, 30 day free trial

Begin your journey by opening a free Esendex account today and get 25 SMS credits.

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Ready? Set? Go!

Learn how to get your service up and running with our simple quickstart guides.

Read our API docs

Not a coder? We’ve got you covered

Our managed services team can help you set up and run your SMS API quickly. From initial configuration to testing and live deployment, we’ll make sure everything is in place so you can start sending messages with confidence.

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“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 Officer, Software at Houseful

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Discover the full power of our SMS API with 25 free messages over 7 days, no credit card required.

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Why choose Esendex?

Having us in your corner ensures that you can support your customers and your business – whatever comes your way.

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20+ years of experience

Industry leading support

An expert and reliable partner

Security and compliance

Solutions designed for you

Flexible and scalable options

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.

One-time password (OTP)

Verify users quickly with secure single-use SMS codes for logins and transactions.

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.

Two-way API

Customers can reply to your text messages for support, confirmations, and updates.

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?

Our SMS API supports multiple languages including cURL, C#, PHP, Java, Ruby, Node and Go. Find out more in our developers’ section.

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.

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Start your free trial

Discover the full power of our SMS API with 25 free messages over 7 days, no credit card required.

START FREE TRIAL