Guidelines
We've compiled regulatory and compliance information to help ensure you're communicating effectively and compliantly around the world.
Locale Summary | |
---|---|
Locale name | United Kingdom |
ISO code | GB |
Region | |
Mobile country code | 234, 235 |
Dialing code | +44 |
Guidelines | |
---|---|
Two-way SMS supported | Yes |
Number portability available | Yes |
Twilio concatenated message support | Yes* |
Message length | Inbound: GSM 3.38=160, Unicode=70 Outbound: GSM 3.38=160, Unicode=70 |
Twilio MMS support | Converted to SMS with embedded URL |
Sending SMS to landline numbers | Twilio will not check whether the number is a landline and will attempt to send it to our carrier for delivery. Some carriers will convert the SMS into text-to-speech messages via voice calls. |
Compliance considerations | SMS-to-voice functionality is in widespread use in the UK, and as a result, Twilio will not reject messages sent to landlines. Please be aware of this fact because it may not be the desired behavior for your application. If this is not the desired behavior, Twilio Support can help. ________________________________________________ Sending cannabis related content is strictly prohibited. _________________________________________________ Message delivery to M2M numbers is on best-effort basis only. _________________________________________________ Twilio strongly encourages customers to review proposed use cases with qualified legal counsel to make sure that they comply with all applicable laws. The following are some general best practices:
_________________________________________________ BT introduced within 2023 strict regulations in order to reduce fraudulent messaging and smishing attempts. Messages sent to BT subscribers with sender IDs related to specific brands will be blocked by default so customers are required to allowlist Alpha Sender IDs related to the specific brands before sending messages with them. Please find more details inBT Protected Brands |
Phone Numbers & Sender ID
Alphanumeric
| Pre-registration | Dynamic |
---|---|---|
Operator network capability | Not Required | Supported |
Twilio supported | --- | Supported |
Sender ID preserved | --- | Yes |
Provisioning time | N/A | N/A |
UCS-2 support | N/A | Supported |
Use case restrictions | N/A | Twilio will start blocking on 06/06/2024 messages submitted from "MEF-Protected Sender IDs" for which customers have not provided an LOA letter. In case you are experiencing delivery issues related to a MEF-Protected Sender ID, please reach out to senderid@twilio.com to provide the LOA proving that you are legitimate and authorised carrier of the traffic related to the specific Sender ID. For more information, visitMEF Protected Sender ID Instructions for UK A to Z (Upper case) |
Best practices | N/A | Protected Sender IDs: Generic Sender IDs: Please refrain from using generic sender IDs like SMS, TEXT, InfoSMS, INFO, Verify, Notify etc to avoid being blocked by network operators. Starting from the 1st November of 2023 the following Alphanumeric Sender IDs will be added to the above list: |
Long codes and short codes
| Long code domestic | Long code international | Short code |
---|---|---|---|
Operator network capability | Supported | Not Supported | Supported |
Twilio supported | Supported | Not Supported | Supported |
Sender ID preserved | Yes | N/A | Yes |
Provisioning time | N/A | N/A | 8-12 weeks |
UCS-2 support | Supported | N/A | Supported |
Use case restrictions | Virgin Mobile no longer support SMS to UK landline numbers | Several UK networks, with EE, Telefonica and SKY being the most notable ones, are actively filtering A2P traffic submitted from International Longcodes. It is strongly recommended to avoid sending from International Longcodes to prevent blocking or filtering. Twilio will stop supporting International Longcodes starting from the 1st of June of 2023 | Short codes can only message users on carriers within the countries in which they are provisioned. AlthoughTwilio can provision short codes in multiple countries, if your customers are not located in the UK, you should not obtain a UK short code. Short codes require express consent from end users before any SMS can be sent; if you cannot obtain consent then you should not use a short code. Twilio and/or the carriers will not support certain types of campaigns, including:
Note: Campaigns dealing with age-restricted content (alcohol, gambling, etc.) are allowed, but will be evaluated on a case-by-case basis by UK carriers. |
Best practices | N/A | It is strongly recommended to use Alphanumeric Sender ID when sending one-way Application-To-Person (A2P) traffic to the United Kingdom (UK). To support two-way requirement to carry on a conversation, Twilio offers Shortcode and Domestic Longcodes. | Refer to our FAQ for short code best practices: https://support.twilio.com/hc/en-us/articles/223134887-Requirements-for-UK-short-codes. |
For the benefit of all our customers, these guidelines are provided to help you comply with applicable requirements and to help ensure Twilio's platform remains compliant with global telecommunications ecosystem requirements. These guidelines represent our current understanding of common compliance requirements generally applicable to Twilio and its customers, and do not constitute legal advice. By posting these guidelines, Twilio makes no assurances regarding the legal compliance of your application built using our APIs. You are expected to understand and abide by all compliance obligations applicable to your specific application. You should check these pages regularly for updates as telecommunications ecosystem requirements continue to evolve and change, and the information below may be updated or changed without notice.