From October 1, 2026, all alphanumeric SMS Sender IDs used to send messages to Austrian mobile numbers must be registered in the official Sender ID directory maintained by RTR (Rundfunk und Telekom Regulierungs-GmbH), Austria's telecom regulator. Messages sent with an unregistered Sender ID will not be delivered.
This article explains what's changing, who is affected, and how Omnisend helps you stay compliant.
Before You Begin
This applies if you send SMS messages to Austrian mobile numbers using a custom Sender ID (branded name).
Required for: Promotional campaigns, transactional messages, and automated notifications sent via Omnisend.
Your Sender ID must have a clear connection to your business — only the company authorized to use a name may register and send under it (e.g., only Store XY may use the Sender ID "Store XY").
After registering your Sender ID, use that value as your SMS Sender Name in Omnisend. Learn more about SMS Sender Name.
⚠️ Critical Deadline
Register your Sender ID before October 1, 2026. From this date, messages sent with unregistered Sender IDs will be deleted by Austrian mobile operators; they won't be labeled or downgraded, they simply won't be delivered.
The RTR directory opens for registrations on July 1, 2026. New entries only become valid 14 days after registration, so plan to submit no later than mid-September 2026.
What's Changing
RTR has introduced strict regulation of alphanumeric Sender IDs (via the 10th amendment to the KEM-V ordinance, published March 25, 2026) to protect consumers from SMS scams and sender impersonation. Key changes:
From July 1, 2026: RTR maintains a public directory of all alphanumeric Sender IDs permitted in Austria.
From October 1, 2026: Austrian mobile operators check every incoming alphanumeric SMS against the directory before delivery:
Sender ID not in the directory → the message is deleted (not delivered).
Sender ID in the directory, but ownership cannot be confirmed → the Sender ID is replaced with "Unbekannt" (Unknown) and the message is delivered.
Sender ID registered and verified → the message is delivered unchanged.
New directory entries become valid 14 days after registration.
Registration is done through mobile service providers, who submit Sender IDs to the RTR directory on behalf of businesses. Once registered, the Sender ID can be used across providers - no single provider gets exclusive rights.
💡 Visit the official RTR announcement for full regulatory details.
Who Is Affected
You are affected if you send A2P (Application-to-Person) SMS messages to Austrian 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)
If you only send SMS with a numeric Sender ID (phone number), registration is not required.
International businesses are affected too. The new rules apply regardless of where your business is located - what matters is that your recipients have Austrian mobile numbers.
Sender ID Requirements
To be accepted into the RTR directory, your Sender ID must:
Have a clear, verifiable connection to your business: your registered business name, brand, or trademark.
Follow the standard alphanumeric format: up to 11 characters, letters and numbers only.
Not impersonate or resemble another organization's name.
RTR reviews all new entries and removes any that don't meet the requirements.
How to Register Your Sender ID
Omnisend handles the registration process on your behalf through our certified telecommunications provider, which works with Austrian mobile service providers to enter your Sender ID into the RTR directory.
Step 1. Go to Store Settings → SMS.
Step 2. In the Countries that require sender's name registration section, find the row for Austria with "Action required" status → Click Resolve to open the Sender ID registration form.
Step 3. Fill out the form with your business details and Sender ID → Click Submit.
Once submitted, your registration is processed and entered into the RTR directory. Your Sender ID becomes valid 14 days after it's entered into the directory. You'll receive an email notification once your Sender ID is active or if any issues arise.
💡 International senders: Your registration is submitted through Omnisend's certified telecommunications provider to ensure compliance with Austrian requirements.
Track Your Registration Status
After submitting your form, track your status under Store Settings → SMS:
Action required: You haven't submitted your registration yet.
Submitted: Your registration has been submitted and is being processed. Allow up to 14 days for the entry to become valid.
Verified: Your Sender ID is active 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 Austria?
International businesses sending SMS to Austrian mobile numbers must still register. Omnisend submits your registration via our certified provider network so your Sender ID is entered correctly into the RTR directory.
What happens if I don't register?
From October 1, 2026, messages sent with an unregistered Sender ID will be deleted by Austrian mobile operators. Unlike some other countries, there is no "unverified" label period - undelivered means your customers never see the message.
Why is there a 14-day waiting period?
New directory entries become valid 14 days after registration. This window gives other businesses the opportunity to legally challenge a registration that infringes on their name or brand. Factor this into your timeline and submit before October 1, 2026.
Can I keep using my Sender ID with other SMS providers?
Yes. Once your Sender ID is in the RTR directory, it's registered to you as the owner, and the registering provider doesn't get exclusive rights. You can send it with that ID through any compliant provider.
Can I use multiple Sender IDs?
Yes, but each Sender ID must be registered separately, and each must have a clear connection to your business.
Will my messages be affected if I send from abroad?
Under the new rules, alphanumeric SMS may no longer be routed to Austrian customers from foreign SMS message centers. Omnisend routes your messages through compliant channels, so no action is needed on your side beyond registering your Sender ID.
Will I be notified when my verification status changes?
Yes. You'll receive an email when your Sender ID is active or if your registration is rejected. You can also check the status anytime under Store Settings → SMS.
Need help? Contact our Support Team via live chat or email at [email protected].