The Commission for Communications Regulation (Comreg) requires all sender IDs used to send SMS to Irish phone numbers (+353) to be registered. This applies to direct senders and to third-party organisations sending on behalf of others. This article covers which sender ID formats are permitted for Ireland and how to complete the registration process with Comreg.
Learn more in Comreg’s documentation.
Before you start
⚠️ From 3rd July 2025, any SMS messages sent to +353 numbers from unregistered sender IDs will be blocked completely.
Permitted sender IDs for Ireland
For sending to Ireland, numeric sender IDs are not permitted. You must use an alphanumeric from name, which must:
be a minimum of three characters and a maximum of 11 characters.
consist of the following permitted characters only:
a–z (lowercase and uppercase, in any combination)
0–9
@, !, #, %, &, (, ), *, +, ,, -, ., /, :, ;, <, =, >, ? or a space character
characters containing an Irish language fada, where technically feasible
not contain any other non-permitted characters, including any accented characters other than the Irish fada.
contain at least one letter.†
not be comprised predominantly of numbers.†
not be generic — for example, SMS, Verify, Dentist, or Flowers would not be permitted.
not be sensitive, offensive, or obscene.
not contain trailing or leading spaces.
not be likely to cause confusion to recipients.
This requirement doesn't apply to permitted Network Dialable (short) numbers.
Your registered sender ID must be unique to your organisation. If your current sender ID is already registered to another organisation, you can:
use a variant of this sender ID which is not currently registered.
appeal to Comreg and provide evidence that the sender ID should be registered to you.
Register your sender ID
Before you start
If your organisation isn't registered in Ireland and doesn't have a CRO number, you must have your company registration documents ready to upload. Combine multiple files into a single ZIP file before uploading.
The process differs depending on whether you are a direct sender (the Sender ID Owner, or SIDO) or a third party or partner sending on behalf of other organisations..
Direct senders
To register your sender ID with Comreg:
Select Sign up.
Select I’m applying to be a Sender ID owner.
Expand the Organisation type drop-down menu and select your business type, then enter your website address in the Organisation Web Address field.
If your company is not registered in Ireland, select the I don’t have a CRO number checkbox. You’re prompted to upload your company registration documents. Select Upload documentation.
Provide the requested business information for:
Registered address
Contact details
This person must approve the sender ID registration which they receive by email.
Business address
If this is the same as your registered address, select the Use the same as Registered Address check box.
Select Next.
Enter the Sender ID you want to register.
You can disregard Assign 3rd Party_. To register another sender ID, select Add Another Sender ID and enter the details._
Select Next.
Read the confirmation information, select the I have read and agreed to the Sender ID Registry Terms and Conditions check box
Complete the Captcha.
Once you have completed this process, Comreg review your application and send the registered contact an activation email so they can set up a password for the account. This email also contains information on whether your sender ID is approved.
After approval
Once your sender ID is approved:
Log into your registry account.
Select My Sender IDs from the homepage. Your sender ID shows as Approved.
Under Actions, select OPA Authorisation, then select Dotdigital EMEA Ltd.
Take a screenshot of the approved Sender ID, and email this to your Dotdigital Customer Success representative.
From here, we ensure the approved sender ID is correctly set up on your Dotdigital account.
You can register additional sender IDs from the My Sender IDs page. If you register multiple sender IDs, send the details of each to Dotdigital so we can set them up on your account or accounts.
Third parties and partners
If you send SMS on behalf of other organisations, there are three ways to ensure sender IDs are properly registered:
Register a single sender ID for your partner organisation, and include the name of the organisation you are sending on behalf of in the message. Example You're a partner organisation, Company A, that sends SMS messages on behalf of a large number of schools. Sender ID: CompanyA Message: ABC School: We are closed today due to adverse weather.
Complete the registration process for each of the organisations you send for. Comreg emails the contact you've listed for each organisation. They need to log in to their registration account and select Dotdigital as their Originating Participating Aggregator (OPA).
Advise each of the organisations you send for to register their own sender ID. The nominated person at each organisation needs to follow the guidance above for direct senders. This means each organisation takes responsibility for its own registration, with less manual data input for your team.
After approval
Once the sender ID approval process is complete, confirm this to Dotdigital and let us know which Dotdigital account each sender ID is used in.