The buyer’s guide to SMS APIs

The number of mobile devices operating worldwide is expected to hit 18.2 billion by 2025 – an increase of 4.2 billion since 2020. So it should come as no surprise that mobile messaging is fast becoming a sought-after addition to a business’ communications strategy.

But not every business has the time or resources to design and implement their own bespoke messaging solution or integrate third-party software. 

This is where SMS APIs, solutions that enable you to offer business messaging capabilities without needing to deploy an additional piece of software, come in.

If you’re wondering how to choose the right SMS API to meet your business needs, you’ve come to the right place. From tips on how to choose an API and subsequently, an API provider to deciding whether an API is even right for you, this online resource will cover what you need to know and more.

Do I need an API?

An SMS API is a solution that allow businesses to seamlessly connect their existing software to the new communications channel. This allows you to benefit from the functionality of the comms channel but from within your own software. No need to learn a new software interface or processes. Plug in your new comms channel and be ready to start sending messages.

If you need to send text messages frequently, in high volumes, or messages that need to be customized (such as multiple dynamic fields like locations and reference numbers), an API may be ideal. 

The following types of businesses typically use a messaging API:

  • Those with their own custom software that was developed in house.
  • Those in the software provider sector – they develop and distribute their own software.

Both will have back-end access and the freedom to integrate the API to their own solution(s).

Want to learn more about SMS APIs?

Our programmable SMS API service allows you to send and receive text messages in bulk, globally to customers.

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Choosing an API provider: Top tips

If you don’t have the resources to develop a messaging platform from scratch or deploy third party software, an API might be an ideal alternative. In addition to giving you time and resources back, you will also benefit from more/better functionality, the ability to scale up or down, improved cost efficiency, security, and more.

The next step is choosing an SMS API provider. But how do you pick one when so many claim to be industry leaders and offer ‘best in class’ APIs? Here are some top tips to help you choose the right provider for your needs…

A customer-centric implementation

Will the implementation revolve around your business and its unique challenges and requirements? The right provider will partner with you, spending time to understand your needs and helping to solve them by fitting message sending capabilities alongside your existing tech in a way that best suits your business.

Secure network routing

Can the provider ensure high quality, secure network routing for your text messages? Ask the following questions:

Learn more about grey routing and why businesses should care

At Esendex, we have direct connections to all major networks which not only ensures secure message delivery to local and international customers, but also via the fastest and highest quality routes.

Image of a group of cartoon people, representing the fact that WhatsApp is widely used to connect groups of people


The availability of the SMS API is important. While no provider can confidently and accurately claim 100% uptime, the most reputable and reliable ones will consistently achieve an uptime of 99.99% availability.

If downtime occurs, they will either let you know in advance or if it’s unexpected, they’ll keep you updated while they work to resolve the issue. And to reduce the likelihood of this issue causing downtime again, they should also perform root cause analysis.


What does your prospective API provider offer by way of reporting capabilities? At Esendex, we provide message delivery status and for MMS, you’ll also be able to see read and click rates.

Network coverage

Does the API provider have network coverage in your markets? Network coverage can impact the deliverability of your messages as much as an unstable, unsecured network infrastructure.

24/7 support

Does the API provider offer 24/7 support to help with any issues that may arise? You may not need to reach out to the support team very often, but it’s good to know that they’re there should you need them. 

The right provider will offer a range of support options round-the-clock to suit your business needs (which may change over time).

At Esendex, not only are our experts available 24/7, but our white-glove support is offered to all. When you become an Esendex customer, you gain access to our full range of support options at no extra cost.

Minimum usage requirements

Will the API provider charge you even if you’re not sending messages? Some providers charge monthly fees regardless of whether you’re using their services while others may charge just for the number of message credits you buy.

API’s ease of use

How user-friendly is the API? Many providers – including us – will claim that their API is user-friendly, easy to set up and use. But how true are those statements really? 

Here are some factors you should look for when deducing the API’s overall ease of use:

A cartoon person looking at their phone while walking

Coding language compatibility

Can the SMS API adapt to various coding languages? From CSS to Java, search for an API that will be compatible with different languages.


How easy is it to scale the API up or down? Your business may change over time. The right API provider will not only offer a robust infrastructure that ensures the API can handle spikes in traffic, but they can also support you with your changing business needs.

Automation capabilities

What automation capabilities can your API support? Here are a few examples of the types of tasks a messaging API should be able to deliver:

Free trial offering

Does the API provider offer a free trial? A free trial is the best way to determine whether or not an API is right for your business. 

Activate the trial, send a few messages, explore the functionalities available to you, examine the reporting capabilities, speak to customer support to gauge their expertise – whatever you decide to do, this will help you get a feel of the API and the provider and how both might work with your business.

Give Esendex a try

Activate your 7-day free trial today and start exploring the Esendex SMS platform and feature-rich capabilities.

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Why work with Esendex

We are a messaging solutions provider with more than 20 years of expertise under our belt, gained from working with a variety of organizations across a range of industries. It’s not just about deploying a messaging solution – our aim is to ensure it’s the right fit for your business, whether it’s an API that allows you to automate your customer comms, a bespoke piece of software, or a combination of both.

Here are a few of the benefits of partnering with Esendex:

Be empowered to send high quality, high performing messages

Did you know that 60% of consumers globally would like to receive critical information, such as payment reminders, account updates, or emergency alerts (e.g. changes to business hours), via SMS? Using our API, you can start sending the reminders and alerts that your customers are asking for.

Think along the lines of:

  • Delivery notifications
  • Order/service updates
  • Appointment and booking reminders
  • Marketing alerts (e.g. back in stock alerts)

Gain peace of mind that your messages have been securely delivered 

Our smart routing and direct connections to major networks mean that we can choose the route that ensures your messages are delivered securely and efficiently. We also never use grey routes.

Because your messages will never change hands before they reach your recipients, you can be sure that they will arrive both quickly and securely. That means your customers and employees (if you’re sending internal communications) will consistently receive the service they expect and your brand’s reputation remains protected.

Receive local support

Esendex might be a global messaging solutions provider, but we’re still committed to ensuring our customers receive local technical support. You will always speak to someone in your own country. 

Additionally, you’ll be assigned to a dedicated account manager, receive a review of your business and technical requirements, have the ability to seek support round-the-clock and more.

Have conversations with customers

While being reminded of upcoming appointments/events or informed of changes to opening hours are very useful, allowing customers to reply to you and engage in conversation is what will help you build long-lasting relationships. Our messaging API will allow you to use your existing tech to send and receive messages as part of a conversation.

Better understand your individual customers

With our API, you can track metrics like send and delivery status and even click and read rates with MMS messages. Add metadata to these messages (e.g. campaign names) and you can use it to analyze responses from individual customers or specific groups. 

Armed with this information, you can then continuously improve the deliverability and quality of your messages.

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APIs: The chance to enhance your communication strategy without deploying additional software

A messaging API gives you the opportunity to gain message sending capabilities without actually having to implement an additional piece of software. Access all the features of this new comms channel from the comfort of your existing solution.

Looking for an API that’s reliable, scalable, and lightweight? At Esendex, we have more than 20 years of experience in helping organizations like yours maximize the benefits of mobile messaging (like SMS). We will get to know your business needs and introduce SMS messaging in a way that best suits you. 

Are you ready to get started?

To learn more about the Esendex API or APIs in general and whether they’re suitable for your business, reach out to us today.