Since July 3, 2025, businesses sending A2P (Application-to-Person) SMS messages to Irish mobile numbers must comply with the new SMS Sender ID Registry rules mandated by the Commission for Communications Regulation (ComReg).
This guide outlines who is affected, what changes are coming, and how Omnisend can help.
Before You Begin
This applies if you send SMS messages to Irish mobile numbers using a Sender ID (branded name).
Required for: Promotional campaigns, transactional messages, and automated notifications sent via Omnisend.
CRO Number: Only required if your business is registered in Ireland. International senders can provide alternative proof of business legitimacy.
After registering your Sender ID with ComReg, use that value as your SMS Sender Name in Omnisend. Learn more about SMS Sender Name.
⚠️ Critical: Unregistered Sender IDs are currently being blocked by Irish mobile operators. Register immediately to restore delivery.
What Changed?
ComReg created an official SMS Sender ID Registry to protect the A2P SMS channel from scams that could harm consumers and organizations.
Key updates:
Only registered Sender IDs can be used for A2P SMS to Irish mobile numbers.
From July 3, 2025: Unregistered Sender IDs will be labeled “Likely Scam”.
From October 3, 2025: Unregistered Sender IDs will be blocked entirely.
Sender IDs must be registered via ComReg’s Sender Registry Portal, accessible only to Participating Aggregators (PAs) or Originating Participating Aggregators (OPAs).
To avoid disruption and protect your sender's reputation:
Register your Sender ID via ComReg’s portal.
Assign Vertex LV and Twilio as your OPA.
Add Omnisend in the Third Parties List.
Ensure all Irish SMS campaigns use a compliant Sender ID.
Who Is Affected?
You are affected if you send A2P SMS messages to Irish mobile numbers and use a Sender ID. This includes:
Promotional campaigns
Transactional messages
Automated notifications
Any branded SMS sent through Omnisend
How to Register Your Sender ID
Follow these steps to register your Sender ID with ComReg:
Step 1. Go to https://senderid.comreg.ie/sender-id-sign-up.
Step 2. Choose "I'm applying to be a Sender ID Owner" and fill in your organization details:
Organization type
Phone number
Email address
Website
Trademark number (if applicable)
Tax number
CRO number (if applicable)
Step 3. Add CRO number (if applicable).
Note: CRO (Companies Registration Office) number is required only for Irish-registered businesses.
If your business is not registered in Ireland, tick "I don't have a CRO Number" and upload acceptable proof of business legitimacy:
Incorporation certificate
Trademark certificate
Charity registration
Irish premises proof
Tax number
Similar documentation
Step 4. Once approved, add your Sender ID in the portal. If registering more than one, click "Add Another Sender ID."
Step 5. In the portal, go to Sender IDs → "OPA Authorisation" → Search for SIA "Vertex LV" → Confirm. Repeat the same steps to add Twilio.
Step 6. In the Third Parties List, add Omnisend.
After assigning Vertex LV and Twilio, Omnisend will register your Sender ID with Irish mobile operators.
How Omnisend Supports Compliance
Omnisend works with Vertex LV and Twilio as the OPA to ensure your registered Sender ID is recognized by Irish mobile networks.
Once you complete registration, assign Vertex LV and Twilio, and add Omnisend as a Third Party, we handle the operator-level setup so your messages are delivered successfully.
FAQ
How long does registration take?
Registration timing depends on ComReg's review of your application. Once approved, Omnisend handles the operator-level setup after you assign Vertex LV and Twilio.
What if I'm not based in Ireland?
You still need to comply if you send SMS to Irish mobile numbers. International senders can provide alternative proof of business legitimacy instead of a CRO number.
Can I use multiple Sender IDs?
Yes, but each Sender ID must be registered separately. Use the "Add Another Sender ID" option in the ComReg portal.
What happens if my registration is rejected?
You'll need to review ComReg's feedback and resubmit your application with corrected information or additional proof of business legitimacy.
Will I be notified when my Sender ID is verified?
Check your ComReg portal account for registration status updates. Omnisend will confirm once operator-level setup is complete.
For exact steps on how to register and assign your Sender ID, refer to ComReg Registry Q&A.