Sender ID Regulation in United Kingdom FAQs

This article addresses the sender ID requirements for sending SMS messages to recipients in United Kingdom.

The ever-increasing smishing & phishing attacks on individuals in the United Kingdom have prompted Mobile Network Operators to implement more decisive measures and restrictions in order to protect the general public against fraudulent activity instigated by malicious actors.

Here, we answer your questions about how to ensure the Sender IDs you use to reach recipients in the UK are compliant to provide unimpeded SMS delivery.

What are the Sender ID requirements when sending SMS to recipients in the United Kingdom (+44)?

1. Organisations are encouraged to use their brand names as part of AlphaNumeric Sender IDs.

2. SMSs sent using Generic Sender IDs, including any variations of these (capitalised, lowercase or a combination) will be blocked. E.g, ALERT, Info, PassCode, etc

3. SMSs sent using international long numbers or non-UK registered short codes will be blocked.

4. Alphanumeric Sender IDs can only selected special characters:

   1. Period/Full Stop ‘.’

   2. Dash ‘-’

   3. Underscore ‘_'

   4. Space ‘ ‘

   5. Ampersand ‘&’

5. SMSs sent with Sender IDs containing special characters outside of the allowed special character set will be blocked. Such characters include the likes of : @ , ! ; % $ * ( ) + = “ < >, etc.

What are the recommended compliant Sender ID types for 1-way and 2-way SMS message delivery to recipients in the United Kingdom?

Organisations sending SMS to UK mobile recipients (+44) for 1-way communication should use alphanumeric sender IDs that are centralised to their own company brand/product.

Organisations sending SMS to UK mobile recipients (+44) for 2-way communication have the option of using either UK (+44) long numbers or shortcodes (starting either with a 6 or 8) that are issued by Mobile Network Operators in the United Kingdom.

You can approach your Whispir CSM if you intend to make use of either a UK (+44) longn umber or shortcode to address your 2-way communication needs.

How is blocking of SMS rolled out by the Mobile Network Operators and when can we see these measures being implemented in the United Kingdom?

The blocking of SMS with certain Sender ID types will be rolled out in phases, with the first phase of blocking activity having started in July 2023. We expect additional phases of more stringent Sender ID blocking activity to be rolled out from September 2023 onwards.

It is important to note that each of the United Kingdom Mobile Network Operators (MNOs) applies their own business rules, that they implement through unique algorithms to which blocking of SMS is applied when looking at the Sender ID. To avoid experiencing different message delivery across different MNOs, we recommend that you ensure your Sender IDs comply with all the requirements of a Sender ID format as described above.

Here at Whispir, we’re committed to guiding you through responding and adapting to these new regulations for sending SMSs to recipients in the United Kingdom. If you have any additional questions, or need to obtain a compliant Sender ID please get in touch with your Whispir Customer Success Manager who can help guide you through this process.