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What are the guidelines for two-way messaging in the United Kingdom?

What two-way messaging options are available?

Clickatell offers the following dedicated two-way number options in the UK:

  • Dedicated long number – You choose a 10-digit long number from a list of available numbers.

  • Dedicated random short code – You’ll be assigned a random 5-digit number.

A short code is country-specific and you'll only be able to use it to send and receive messages in the UK.

What are the expected provisioning times?

Clickatell holds stock of long numbers and they are therefore available immediately after purchase.

Short codes require approval from all supported mobile carriers. We'll procure the short code and coordinate the approval process on your behalf. This process can take around 8-12 weeks.


What are the costs involved?

Only applicable to our self-serve clients. If you are on one of our paid packages, please reach out to your account manager or our support team.

Both long numbers and short codes usually have once-off application fees, as well as monthly subscription fees. You pay a per-message fee for all outgoing messages that you send from your number, but all incoming messages are free.

To see estimated pricing, go to the Clickatell pricing estimator, choose the United Kingdom, select your two-way messaging option of choice, and indicate your expected outbound message volumes.


Which two-way messaging option is best for my business?

Long numbers

A UK long number is a flexible and cost-effective option and can be successfully applied for almost all two-way messaging use cases.

  • Appointment reminders Reduce the number of “no-shows” by sending appointment reminders for medical appointments, vehicle servicing, real estate agents, recruitment agencies, or any other service-related business. For example Your dental appointment with Dr. Smith is scheduled for 9 January, 14:00 pm. Reply cancel or confirm.

  • Customer alerts and notifications - Improve customer experience with timely and instant notifications. For example Hi Adele. Your flight SA34009 will be delayed for 2 hours. We apologize for any inconvenience. Please have a free coffee on us at Coffee Café with coupon 38274.

  • Opt-out compliance – Use a long number as a way for recipients to opt-out of your list with a simple keyword to comply with ICO regulations.

  • Booking and payment confirmationsInstant confirmation on purchase or booking set your customer’s mind at ease. For example: Thank you for your purchase at We've received your payment for order #82492. To track your order, reply with your order no.

Short codes

Short codes are generally used by larger brands with significant two-way messaging volume requirements. A short code is short and therefore very recognizable which makes it a good option if you want potential customers to reach out to you first. Advertise your short code to ensure that your customers know how to reach you.

  • Competitions – text-to-win competitions are a great way to get exposure for your brand. For example: "Text ‘XX BRAND NAME’ plus your name+email address to 60777 to win a trip for four to Disneyland. See for terms."

  • Lead generation – SMS is a very cost-effective way to make it really easy for potential customers to show interest. For example: "SMS your name to 38264 and we’ll call you back with a quote."

  • Opt-in for marketing lists – For example: "SMS your name to 82625 to receive our monthly discount coupons."


Best practices

Here is a short checklist of general best practices for SMS campaigns to keep in mind if you are sending out marketing messages.

It is recommended that you use a dedicated two-way number in the UK for your brand. A dedicated long number or short code provides better control and visibility for your brand as well as a better customer experience for your customer. Sharing a number with other businesses means that your customers will have to correctly type a specific keyword pre-registered by your business in the body of the SMS for the message to be routed to you correctly. By using a dedicated number, your customers will start to recognize and trust messages sent from your number as the messages will likely all display in the same thread.

It is also recommended to whitelist URLs that will be included in the message from the brand to customers to ensure successful delivery. Please reach out to your Account Manager or contact our Support team to learn more.


Regulatory information


Applying for a two-way number

Sign up for a Clickatell Platform account here and apply for a two-way number from within your account. Here are step-by-step guides if you need any help along the way:

During the festive season, some network carriers in the United Kingdom implement a freeze period on short code processing. The freeze period usually ranges from mid-December to mid-January. It is therefore recommended that short code provisioning and amendments/migrations are done before the freeze period to avoid delays.


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