SMS Gateway: Definition, Uses, and How They Work

TL;DR

A short message service (SMS) gateway bridges computers and mobile phones, letting businesses and individuals send or receive text messages without a physical handset. Modern gateways are software-based, support bulk messaging, protect sender privacy, and come in several types — direct, Subscriber Identity Module (SIM)-based, and spreadsheet-driven. Choosing the right vendor involves weighing factors like API availability, international reach, free trials, and fee structures. Compliance with the Telephone Consumer Protection Act (TCPA) is mandatory before launching any SMS campaign.

What is an SMS gateway?

An SMS gateway allows your computer to send or receive text messages. A variant of this system will enable you to use a multimedia messaging service (MMS) for more complex communications.

You want to send a text message, but you don't want to use your phone. It's not impossible! You'll just need an SMS gateway. An SMS gateway is an interface, typically provided in app or computer program form. Use it, and your message can shoot from your computer to a phone (or vice versa).

How have SMS gateways evolved from hardware to software?

Years ago, SMS gateways were offered as hardware. You'd pick up a physical tool and use it to do your work. Now, you must select a vendor partner, install some kind of software, and you're ready to go.

Multiple types of SMS gateways exist, including:

• Direct. Vendors offer programming that can translate your notes into text messages, and you'll get responses from phones on your computer. Most vendors offer multiple protocols to choose from. 
• Gateway. Start with a SIM card, and install it within your SMS gateway. All of your messages will seem like they originate from your phone. 
• Spreadsheet. Begin with a list of numbers in software on your computer, and use the gateway to send the same note to each one. 

Any message you send through the SMS gateway is limited to 160 characters. If you have more to say, your note could get sheared into multiple messages. And you have no control over which comes first.

Longer, more complicated messages benefit from multimedia messaging service (MMS) apps. You won't run into character limits with this solution. 

How are SMS gateways used?

Why should you bother with yet more software when your phone is always within reach? SMS gateways come with plenty of benefits almost anyone might need.

For example, about 49 million customers have opted into receiving SMS notes from brands. If you're on the marketing team, you don't want to tap out messages to each and every subscriber. An SMS gateway can dramatically reduce your workload.

You may also need to send a text message to someone without revealing your private phone number. SMS gateways help you to protect your privacy.

What features do SMS gateway vendors offer?

SMS gateway vendors offer tantalizing features, such as:

• Reliability. Your cell service may come and go, but your vendor is always online.
• Dedicated numbers. Your messages always seem to come from one number, so they're less likely to head into spam folders.
• Multiple users. Everyone on your team could log on and work, even if you're all on at the same time.
• Expanded reach. Some services let you reach overseas clients without added global charges.

What are the legal requirements for SMS marketing?

While your company might be eager to jump on the messaging train, remember that you must have client consent before messaging begins. That requirement is part of the Telephone Consumer Protection Act, and violating it can be expensive.

Papa John's learned that with a class-action lawsuit about unwanted texts that could have cost the company more than $250 million.

How can you send texts from your computer using email?

Log into your computer, and you can send text messages to a phone with an SMS gateway or MMS gateway. In some cases, you don't even need software to make it work.&

Here's how to get started:

1. Compose. Don't use fancy HTML or scripting. Write in plain text only.
2. Research. You must determine the recipient's phone number and provider. With that, you can use this domain chart to fill out the "to" box.
3. Prepare. Type in your recipient's phone number, the "@" symbol, and the provider domain. Keep these all squished together, so they look like an email address.
4. Send. When you're done composing, shoot that note out.

Which SMS gateway should you use?

Many companies want your SMS gateway business, and that means you have plenty to choose from.

Sorting the clever from the crooked isn't easy, especially if you're new to this form of messaging. Consider these notes. Most vendors also provide an application programming interface (API) for deeper integration.

We're just scratching the surface of features and comparisons here. For more in-depth reporting, check out SMS Comparisons. This company specializes in comparisons within this space.

Frequently asked questions

What is the character limit for messages sent through a short message service (SMS) gateway?

Messages sent via an SMS gateway are capped at 160 characters. If your message exceeds this limit, it may be split into multiple separate messages, and you have no control over the order in which they are delivered. For longer or richer content, a multimedia messaging service (MMS) gateway removes this character restriction.

Do I need special software to send a text from my computer?

Not always. You can send a text message from your computer using a standard email client by addressing the email to the recipient's phone number combined with their carrier's domain (formatted like an email address). However, for bulk messaging or business use cases, a dedicated SMS gateway software solution is recommended.

What are the legal requirements before sending short message service (SMS) marketing messages?

Before sending any SMS marketing messages, you must obtain explicit consent from your recipients. This is a requirement under the Telephone Consumer Protection Act. Failing to comply can result in significant financial penalties — as illustrated by a class-action lawsuit against Papa John's that could have exceeded $250 million in damages.

What is the difference between a direct short message service (SMS) gateway and a Subscriber Identity Module (SIM)-based gateway?

A direct SMS gateway uses vendor-provided software and protocols to translate and deliver messages between computers and phones. A SIM-based (or 'gateway' type) solution uses a physical SIM card installed in the gateway device, making outgoing messages appear as though they originate from a standard mobile phone number.

How do I choose the right short message service (SMS) gateway vendor?

When evaluating vendors, consider whether they offer an application programming interface (API), support international markets, provide a free trial, require prepayment, and charge setup or monthly fees. Vendors like Bulk SMS, Click Send, Twilio, and Clickatell each have different fee structures, so comparing them side by side — using resources like SMS Comparison — can help you find the best fit.

Can multiple team members use the same short message service (SMS) gateway account simultaneously?

Yes. Many SMS gateway vendors support multi-user access, allowing everyone on your team to log in and send messages at the same time. This makes SMS gateways particularly useful for marketing teams managing large subscriber lists, as it eliminates the need for individuals to send messages from personal devices.

References

SMS Gateway: From Email to SMS Text Message. (August 2019). Lifewire.

45 SMS Marketing Statistics Your Customers Wish You Knew. (October 2020). G2.

Papa John's SMS Practices Could Cost It Over $250 Million in Damages. Marketing Dive.

How to Send a Text Message From Your Email Account. (July 2021). DigitalTrends.

SMS Gateway Providers Comparison 2021. (May 2021). SMS Comparison.