Skip to main content

When to Use Short code vs Toll-Free SMS

Should you use short code or toll-free sms? We compare the two to help you answer.

More about Programmable SMS

When to Use Short code vs Toll-Free SMS

Short code

A short code is a five or six digit telephone number used to send and receive SMS and MMS messages to and from mobile phones. There are two types of short codes: vanity and random. A vanity short code is a specific set of digits that you choose, while a random short code is assigned to you.

Short codes can send higher volumes of messages, compared to long codes, so wireless carriers individually audit every short code for its intended use. While this approval process typically takes eight to twelve weeks, it means that short codes are not subject to carrier filtering. In fact, short codes are the only way to ensure deliverability of your messages without the risk of them being filtered by carriers.

Due to their high throughput, short codes are subject to a strict set of requirements. The CTIA has a list of rules that all short code programs must follow. For example, there are specific language requirements you must include in your advertisements, terms page, and messages. Interpretation and enforcement of these rules varies from carrier to carrier. Short code programs are subject to random compliance audits conducted by carriers and the CTIA — your short code could get shut down if it doesn’t meet their standards.

There are two costs to consider for using a short code: The cost to lease a short code and the volume cost of sending messages from a short code. Short codes must be leased from a national registry for a minimum of three months at a time. Vanity short codes are easier for consumers to remember, making them more expensive than random short codes. Examples of applications best suited to a short code include marketing communications, large one-to-many notification bursts, time-sensitive alerts, and high volumes of one-to-one transactional notifications.

Toll-Free SMS

Toll-Free Short Message Service (Toll-Free SMS) is used to send text messages from Toll-Free numbers (8XX) to other mobile phones. For businesses with an existing Toll-Free number, you can text-enable it. Having the same number for both voice and messaging means a better user experience for your customers. Use cases with a large volume of SMS marketing messages are not acceptable for Toll-Free.

Toll-Free messaging works best when your use case is person-to-person, such as customer support or sales, with both the sender and the recipient having a conversation via text. However, because Toll-Free numbers can support a higher throughput of messages per phone number than traditional ten-digit numbers, some businesses do choose to use Toll-Free numbers for one-way communications like alerts and notifications.

Short code or Toll-Free SMS?

When deciding between a short code and Toll-Free SMS, the important thing to keep in mind is that they rely on separate sets of infrastructure and spam filters. A responsible communications provider should have a series of checks and balances built into its contract process to ensure that the Toll-Free SMS channel remains spam-free. Though short codes both send and receive messages, the reality is that short code SMS is routed through a different infrastructure than Toll-Free SMS. Consequently, the deliverability of these two forms of communication can differ widely. Locked into a contract with your current voice provider? Most carriers will provide a letter of authorization to take your messaging business to a different provider, allowing you to get started without having to stay on an outdated contract.

Short Code vs Toll-Free SMS

Screen Shot 2019-06-14 at 9.30.36 AM


Both Short Code and Toll-Free can be very effective for SMS based on the right use case. For high volume A2P messages, like appointment reminders or verification messages, short code is the right option to avoid a higher rate of filtering. For use cases where you want to start a customer interaction on SMS and transfer it to a phone call, Toll-Free is a better option. For branded interactions, vanity Toll-Free numbers reinforce brand recognition and make your messages immediately identifiable. One of the trickiest things about short codes is recognizing when you need one. Mass A2P messages are suited for a short code, while Toll-Free numbers come with a lot of industry-mandated red tape for sending A2P high volume messages.Download the data sheet for more information.