Messaging API
Unify your communications with our multichannel API
Businesses today rely on multiple channels – including SMS, RCS, WhatsApp, email and voice – to deliver engaging communications. Our multi-channel API allows you to manage all these channels in one place, so you can choose the most appropriate one for your message type and customers’ preferences.
Seamlessly connect our powerful multichannel API with your business systems to unlock new messaging capabilities and analytics that drive improvements.
Security and scalability come as standard with our industry-leading multi-channel API, which has been designed for both developers and no-code teams, and can be up and running within hours.
The Esendex multi-channel API is build-once, so users benefit from continuous support, regular updates and new features that improve usability and performance.
Everything you need from a multichannel API
Fast integration
Our multichannel API has been designed to integrate with your business applications quickly – and be up and running in a matter of hours. Quickstart guides and 24/7 professional support make it easy for developers and no-code teams to implement the API.
Secure
Protect your customers’ data across multiple channels. Esendex is ISO 27001 accredited – helping you protect customers’ data and comply with GDPR.
Single access point
Add and manage multiple channels from a single access point for ease and compliance.
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 email 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 email:
// 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 email 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.
“Operationally, WhatsApp offers significant engagement opportunities – from outbound notifications, reminders and status updates to marketing and promotions. The combination of chatbot automation and WhatsApp has also had a direct impact on our bottom line”
Lucie Riley – Chief Operating Officer, Rhenus Home Delivery
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 every channel with our powerful API
Flexible
Use your customers’ preferred channels and reduce friction as they move between them.
One view of performance
By bringing all your communications channels together, you can quickly identify areas for improvement using advanced reporting tools.
Consistent customer experiences
Deliver a consistent brand experience for customers as they move across channels, with SMS, RCS and WhatsApp deployed from a single platform.
Easily connect to industry-standard applications
Integrate with industry-standard marketing, CRM, ecommerce and other platforms
Automate routine tasks
Automate repetitive and time consuming tasks linked to a conversation, giving agents more time to communicate with the customer.
Preview and test
Quickly preview emails to ensure they render on mobile, desktop and across all major email clients. Our A/B testing tool checks up to 10 variants at a time, so you can hone your offers and design to send the best email, every time.
FAQs
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Is the multichannel API secure and GDPR compliant?
Is the multichannel API secure and GDPR compliant?Yes. Your customers’ data is protected to the highest standards because Esendex is ISO 27001 accredited and supports compliance with GDPR.
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( Missing number ) How many applications integrate with the multichannel API?
We offer [insert number] integrations, which allow users to easily manage conversations – from automated reminders to two-way customer service messaging.
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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.
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What programming languages are supported?
JavaScript, Python, Java, C#, PHP and cURL are all supported, enabling fast integration.
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Is there a sandbox or testing environment available?
Yes. You can test and simulate messages safely using our dedicated sandbox environment.
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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.
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Are there templates or pre-configured integrations available?
Yes. Our API works with platforms like Salesforce and Zapier, alongside pre-built message templates.
