From June 7, 2025, all SMS Sender IDs to Spain must be registered. Unregistered IDs are blocked, which impacts SMS delivery.
This article explains what's changing, who is affected, and how to submit your Sender ID for compliance through Omnisend.
Before You Begin
This applies if you send SMS messages to Spanish mobile numbers using an alphanumeric (branded) Sender ID.
Required for: Promotional campaigns, transactional messages, and automated notifications sent via Omnisend.
Authorized representative: Ensure this person has a Spanish digital certificate or eIDAS ready before you submit. They'll need it to confirm the registration in the Spanish regulator's portal. Without this confirmation, your Sender ID remains unregistered.
After you register your Sender ID, use that value as your SMS Sender Name in Omnisend. Learn more about SMS Sender Name.
⚠️ Already in effect: Sender ID registration in Spain has been mandatory since June 7, 2025. Messages sent with unregistered alphanumeric Sender IDs are blocked by Spanish mobile operators.
What's Changed
Spain now requires all alphanumeric Sender IDs to be registered before they can send messages to Spanish mobile numbers. This protects consumers from SMS fraud and brand impersonation.
Key changes:
All alphanumeric Sender IDs used in Spain must be registered before they can send.
Sender IDs must match your registered company name, trademark, domain, or another lawful identifier.
Messages sent with unregistered Sender IDs are blocked at the operator level, and they will not be delivered.
💡 What's an alphanumeric Sender ID? It's the branded name (letters and numbers, up to 11 characters) that appears as the sender name in your SMS. For example, "Omnisend" or "YourStore".
Who Is Affected
You are affected if you send A2P (Application-to-Person) SMS messages to Spanish mobile numbers using an alphanumeric Sender ID. This includes:
Promotional campaigns (e.g., sales, offers)
Transactional messages (e.g., order confirmations, shipping updates)
Automated notifications (e.g., abandoned cart reminders, workflow messages)
Note: If you only send SMS with a numeric Sender ID (phone number) or a short code, registration is not required.
Required Information for Spain Sender ID Registration
Omnisend submits your Sender ID registration through Twilio, our certified telecommunications provider, on your behalf. You'll need to provide:
Sender ID: The exact name customers will see (e.g., "YourBrand"). Must match your registered company name, trademark, or domain.
Company Details:
Legal entity name, exactly as it appears in an official authority register;
Business address;
Website URL.
Authorized Representative Details:
Full name;
Role/title;
Work email address;
Confirmation that this person holds a Spanish digital certificate or eIDAS to access the regulator's portal.
Legal Representative Details: Required by the Twilio Console submission. Provide full name, role, and contact details.
Use Case Description: Brief explanation of how you use SMS (e.g., "Promotional campaigns and order updates for e-commerce customers").
Omnisend prefills sample messages and estimated monthly volume when submitting on your behalf.
💡 International senders: Your registration is submitted through Twilio, Omnisend's certified telecommunications provider, to ensure compliance with Spanish requirements.
How to Submit Your Sender ID Registration
Omnisend handles the registration process with the Spanish regulator on your behalf. To start:
Step 1. Go to Store Settings → SMS.
Step 2. You'll see a notification to resolve your Sender ID for Spain compliance → Click the link to open the Sender ID registration form.
Step 3. Fill out the form and provide the required information (listed above) → Click Submit.
Once submitted, the status will change to "Submitted". Omnisend forwards your registration to Twilio, which submits it to the Spanish regulator.
Next step: The regulator will email your authorized representative with instructions to confirm the registration in the regulator's portal. A Spanish digital certificate or eIDAS is required to log in.
You'll receive an email notification once your Sender ID is verified or if any issues arise.
⚠️ Action required by your authorized representative: The Spanish regulator requires your authorized representative to confirm the registration directly in the regulator's portal. Until they do, your Sender ID is not registered and messages from it remain blocked. Make sure their digital certificate or eIDAS is ready before you submit, and that they are watching for the regulator's email.
Track Your Registration Status
After submitting your form, you can track your registration status under Store Settings → SMS:
Action required: You haven't submitted your registration yet.
Submitted: Your registration has been submitted and is awaiting confirmation by your authorized representative in the regulator's portal.
Verified: Your Sender ID is approved and compliant. You'll receive an email confirmation.
Rejected: Your registration was not approved. You'll receive an email notification. To resubmit, return to Store Settings → SMS and complete the form again with updated information.
FAQ
What if I'm not based in Spain?
You still need to comply if you send to Spanish mobile numbers. Omnisend submits international registrations through Twilio as a certified provider.
What if my authorized representative doesn't have a Spanish digital certificate or eIDAS?
The Spanish regulator requires a Spanish digital certificate or eIDAS to confirm registrations in their portal. If your authorized representative doesn't have one, they'll need to obtain it before you submit. Contact a Spanish digital certificate provider or eIDAS issuer for assistance.
How long does registration take?
Verification typically takes up to 2 weeks after your authorized representative confirms in the regulator's portal. We recommend submitting at least 3–4 weeks before you plan to send.
What happens if I don't register?
Messages sent with unregistered alphanumeric Sender IDs are blocked by Spanish mobile operators. This is already in effect as of June 7, 2025.
Will I be notified when my verification status changes?
Yes. You'll receive an email when your Sender ID is verified or rejected. You can also check the status anytime under Store Settings → SMS.
What happens if my registration is rejected?
Reach out to our Support Team to confirm the rejection reasons. Then, you'll need to resubmit the form again in Store Settings → SMS. Make sure all documents are complete and your Sender ID is clearly linked to your registered business name, trademark, or domain.
Can I use multiple Sender IDs?
Yes. But each Sender ID must be registered separately. Repeat the submission process for each one.
💬 Need help? Contact our support team via live chat or email at [email protected].