What are SMS short codes?

An SMS short code is a 4, 5 or 6 digit number that is used by organisations to send and receive SMS (or MMS) messages. They are generally advised when sending high-volume, bulk SMS campaigns.

Why do businesses use SMS short codes?

Promotional messages

If you are sending bulk SMS messages to promote your goods or services then you will need a short code.

Short codes are what allow you to execute opt-in campaigns that require “a clear and obvious” response from your customers, e.g.  “Text SUBSCRIBE to 12345 to receive special discounts to your phone”.

Under GDPR, you also need to make it easy for customers to withdraw marketing permissions. e.g. “Reply STOP to opt out”.

In these instances, SUBSCRIBE and STOP are what’s known as keywords. Keywords are particularly important when using a shared short code (more on that below). They also help you segment your audience based on their particular interests and the campaigns they’ve engaged with. 

Bulk campaigns

A long code is the traditional digit phone number with 10 or more digits. These are intended for ad hoc, one-to-one texting. There is a strict limit of one per second when sending from these numbers. 

With a short code, you can send approx. 100 per second, making it far more suited to bulk campaigns and time-sensitive messages that need to go out to a large group of customers.

Furthermore, when you send a large number of texts at once, or typically send a high volume throughout the course of a day, using a long code you run the risk of triggering the network carriers’ spam filters. This means the message won’t reach the intended recipients’ inboxes. As SMS short codes are vetted in advance by the carrier, they are not penalised in the same way.

Rich messages

If you would like to send customers digital vouchers, or even simply images, then you need a short code. Long codes will not allow you to send these multimedia messages at scalel.

Using a short code also reduces the odds of the customer incorrectly entering the wrong number in the first place. This happens surprisingly often!

Are there any advantages to using a long code?

There aren’t any advantages per se, but long codes are of course commonly used by businesses, just not in a promotional capacity. You may prefer to use a long code, and it may even be more suitable for your brand, depending on your specific aims and requirements.

For example, if you want to keep consistency across all of your contact details, then using a short code for certain campaigns or services won’t allow you to do that. You’ll still need to have your long code to make and receive phone calls.

If you have no aspirations to send bulk marketing campaigns, but instead intend to use SMS for one-to-one customer support then there’s no need for a short code. 

Where do you get a short code from?

Short codes are essentially leased from your national telecoms registry. This is something you can look after yourself, but it is recommended that you go through your SMS service provider to get the best rates and to expedite the process.

Shared vs dedicated short code; which is better?

A shared short code is used by multiple brands at the same time. In this arrangement, each brand has specific keywords that only they can use in their campaigns. This allows the messages sent by customers in reply to that short code to be delivered to the right brand.

Typically, a brand will use their own name as the keyword when operating under a shared code. A shared short code has the dual advantage of being cheaper and quicker to set up than a dedicated one.

However, a shared short code does have some serious drawbacks. If one of the brands using it misbehaves or breaks the rules then the code will be added to a blacklist, meaning all of the other brands sending from that code will be affected. For this reason, shared codes are likely to be phased out by carriers at some point soon.

A dedicated short code belongs only to you. Brands will choose this option when they want total freedom over the keywords they can use in their campaigns and are unconcerned about the extra cost.

What is a “vanity” shortcode?

If you apply for a dedicated short code then the number allocated to you will be randomly generated. Alternatively, you can request what’s called a “vanity” short code. This costs more, but allows you to choose your own number (pending availability of course).

You may desire a particular sequence of numbers because it will be easier for customers to remember or because it bears some relevance to your brand.