The low cost SMS API for developers

Pay only for delivered messages

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Most SMS API companies charge for undelivered texts

At the SMS Works, we only bill you for delivered text messages.

Watch our 60 second video to find out why you've been paying too much.

Don't Pour Away Your SMS Credits

On average, 18.5% of SMS credits are wasted.


Undelivered Texts

Almost all SMS companies charge you for undelivered texts, when they haven't been charged themselves. We will not charge you for undelivered texts.

Messages Just Too Long

For messages that are just longer than 160 characters you'll be charged 2 SMS credits. Our AI message optimiser can help you to avoid this.

Unicode Characters & Emojis

Special characters use more credits. Our unicode and emoji filters will help to strip these out before your messages are sent.
The University of Oxford
Severn Trent

Remarkably Low SMS API Pricing

Our prices are amongst the lowest in the UK. Message costs start at 3.95 pence + VAT and go as low as 3.55 pence for larger volumes.

Savings over 30%

On average, our customers save over 30%. Compare us with other SMS Gateway companies on our price comparison table. Contact us for a quote if you'd like us to beat an existing price.

High Volume Customers

For high SMS volume customers, sending and receiving over 50,000 texts a month, we offer even lower rates. With our free SMS API, you only pay for SMS credits; there’s no contract or minimum order.

Only Pay for Delivered Messages

We only charge you for delivered messages. Failed texts are credited straight back to your account.

Additional Savings

Almost all SMS companies charge for failed texts, when they haven't been charged themselves. You can save as much as 18% by not paying for undelivered texts.

Detailed Delivery Reports

Our delivery reports give you a detailed outcome of all texts sent, including refunded SMS credits.
GMB Union
KIA Motors
Clydesdale Bank
Hammsersmith & Fulham
My Urban Jungle

Fast, Reliable, Robust

We've invested heavily to make our UK SMS API as reliable as it can possibly be. Our platform has been built to withstand the rigours of the most demanding applications.

Secure & Compliant

We understand that data protection and security are crucial to you. We've gone the extra mile to ensure that our platform exceeds all the data protection requirements under GDPR. All our data centres and servers are UK based.

Keeping Customers Happy

Read SMS API testimonials from our customers.
SMS API platform

Comprehensive SMS Insights

SMS Insights uncovers hidden stories in your SMS activity.

What's going on?

A series of automated charts and tables provide actionable insights into your SMS campaigns.
Dive deep into the data and reveal ways in which you can reduce costs, increase effectiveness and elimate wastage. Check out our short video which shows how we can help you.

Reliable Tier 1 Connections

We only use the most reliable tier one connections, direct to UK networks. Text messages sent within the UK stay in the UK.

No Grey Routes

We never use international or SMS grey routes to send and receive SMS. Although grey routes may seem like a great, low-cost SMS option, they are notoriously unreliable.
Swansea City
MRI Real Estate Software
Marshall Motor Group

Simple & Easy to Set Up

No set-up fee. No contract. Simple, pay-as-you-go service.

No-contract SMS API

Free Test Account

Your free SMS account comes with 50 free text credits. Let us know if you need more.

If you'd like to be able to receive replies to your texts, you can also have a 1 week free trial of a UK reply number.

SMS API sample code

Copy & Paste API Snippets

We’ve put together a comprehensive range of ready to go scripts in the most common languages. Simply copy and paste.

Whatever your preferred language, our goal is to make your SMS integration as fast and simple as possible.

SMS API support

Fast, attentive support

If you have questions that aren't quite covered by the https API documentation, we always get back to support queries within the hour.

Our objective is to have you up and running with your SMS integration in the shortest time possible.

Two-way Conversations With Your Customers

Low cost reply numbers (long codes)

Receive SMS replies to your text campaigns with a low cost reply number. SMS Replies can be routed back to you by email or we can simply post replies to a URL of your choice.

Free trial

Our free 7-day trial allows you to test the long code service before making any kind of commitment.

SMS Short Codes

A keyword on our 88440 shortcode allows you to add a text response option to your marketing channels.

What's included

  • No setup fee

  • Replies forwarded to URL or Email

  • Just a 3-month minimum term

  • Configurable auto-responses

SMS autoresponse
SMS credit overdraft

Peace of mind

You want to be sure that your SMS will continue to send,
especially when you're concentrating on something more important.

SMS Credits Overdraft

SMS Credits Overdraft

Running out of SMS credits is one of our customers' biggest concerns. The last thing you need is crucial texts to stop because of an admin issue.

Credits don't expire

Once you've bought SMS credits from us, they won't expire. Surprisingly, some SMS providers remove your credits if they haven't been used after 12 months.

SMS API Features & Tools

Our Rest API is stacked with tools, designed to make working with us as simple as possible. Whether you’re a freelance developer, or working in a large team, our tools are quick and easy to use.

Receive Delivery Reports

Every SMS marketing campaign you send generates a delivery report. Delivery reports can be accessed both via the HTTPS API and by logging into your account.

Schedule a text campaign

SMS via API campaigns can be scheduled to run on the date and time of your choosing. Send one message at a time or several as a batch.

Receive Text Replies

Receive SMS replies to your texts using our virtual mobile numbers. Incoming texts can be forwarded to an email address or URL of your choice.

AI Optimisation

Our message optimiser AI uses Chat-GPT to shorten messages that are just over the SMS character limit.

Send Batch SMS

If all of your contacts should receive the same text, then the batch send tool allows you to send a bulk SMS campaign.

Retrieve Messages

Retrieve text messages that match any given search criteria, either via the API or your SMS Works account screen.

Use Dynamic Sender IDs

Send SMS messages with your chosen originator. There are no restrictions and you don't need to register your sender IDs in advance.

Send Long Messages

A standard text is 160 characters long. Our SMS API allows you to send & receive SMS messages of up to 1280 characters. Long text messages arrive as one message.

Global SMS

We connect with networks in over 200 countries. Wherever you're planning on sending and receiving SMS, we're able to deliver.

Comprehensive Error Codes

To help you fully understand why a text is undelivered, we provide more than 25 error codes. This vital info can be used to clean your contact data.

SMS OTP Platform

Generate, send and verify SMS One-Time Passwords, to add extra security to your sign-up forms and transactions.

SMS Credit Overdraft

Remove the worry of running out of credits by organising an SMS credits overdraft. An SMS overdraft is free and allows your account to keep sending text messages when your balance hits zero.

SMS Insights

Our automated charts and tables display actionable insights. Track, measure and share your charts and data to improve the effectiveness of your SMS campaigns.

Webhook Monitor

Sends you an email alert if your incoming SMS or Delivery Report webhooks stop working or are unresponsive.

Unicode Replacement

Automatic replacement of common unicode characters with their GSM equivalents (e.g unicode hyphens and apostrophes).

Emoji Filtering

Optionally configure your account to remove all emojis from your texts, avoiding using more text credits than you intended.

Cambridge University
Department of Transport
Cancer Research UK

Whatever language you choose We've got you covered

Send SMS with cURL
Send SMS with c#
Send SMS with Node
Send SMS with Java
Send SMS with PHP
Send SMS with Python
Send SMS with Ruby
Send SMS with Go

What can an SMS API be used for?

SMS sending services have traditionally been seen as a marketing tool. It’s certainly a highly effective way of getting your message in front of your target audience.

But there are so many other ways that you could use a business SMS service in your business. This is by no means a complete list, but could give you some ideas.

  • SMS Delivery Notifications

    Let your customers know exactly when and where to expect delivery of their order. This can hugely reduce delivery failure rates.

  • SMS for 2FA (2-factor authentication)

    Improve your security by using 2FA SMS. Use SMS to send and receive dynamic codes for secure login or payment transactions.

  • Text Appointment Reminders

    Reduce the number of 'no shows' by sending an SMS appointment reminder 24-hours in advance. Missed appointments can be reduced by up 70%.

  • Job Opportunity Alerts

    Inform candidates about new jobs opportunities with well-timed text alerts. Include an SMS reply option so candidates can register their interest.

  • SMS Customer Surveys

    Gather valuable customer opinion data with short surveys by text. Use the data to improve your customer service and satisfaction.

  • Text Order Confirmation

    Inform customers by text that their orders have been received. Using an SMS HTTPS API, the text can include items ordered and total paid.

  • SMS Customer Support

    Handle customer support and queries by text. Provide instant support and improve your customer satisfaction.

  • Event Invitation

    Increase attendance at your events with a personal invitation by text. Offer discounts to those that respond by SMS.

  • Highlight Important Emails

    Increase read rate of your emails by drawing attention to important emails by SMS. Email read rate can be increased by as much as 55%.

  • SMS Workflows

    Connect The SMS Works with other applications using Zapier. No coding is required. It’s a quick and easy way to automate sending an SMS.


What is an SMS API?

An SMS API (Application Programming Interface) is a set of tools which allows the capabilities of one computer application to be made available to another, so that SMS messages can be sent and received.

The API specifies how software components should interact and follows a set of predefined rules, allowing developers to build SMS-based workflows into their own applications.

What is an SMS API?

How does an SMS API work?

An SMS HTTPS API simplifies the whole process of sending a text from a system to a mobile handset. It acts as a bridge between your organisation and your customers or members of staff.

The SMS API removes the hassle of having to write and deploy specific code to handle the complexities of multiple mobile phone networks that operate different protocols and infrastructures.

How does an SMS API work?
SMS Works FAQs

Frequently asked questions

Contact the SMS Works

The SMS Works

A Fairer Approach to Pricing

SMS API Pricing has dropped by 63% since 2001.

Falling Prices
20 years ago it cost about 9.7 pence to send a business SMS to a mobile number. In 2022, it costs around 3.5 pence. That’s an astonishing drop. In almost all cases, SMS providers simply aren't passing on the price reduction to customers.
Delivered Only
Paying for undelivered texts when your existing provider doesn't have to, isn't a very open way of operating. By looking at your SMS delivery reports you’ll be able to see how much you’re currently spending on failed texts.