Austria is introducing mandatory registration for alphanumeric SMS Sender IDs from 1 October 2026 as part of a broader effort to reduce SMS fraud, sender impersonation, and scam messaging.
The new requirements are being introduced by RTR (Rundfunk und Telekom Regulierungs-GmbH), Austria's telecommunications regulator, and follow a growing global trend towards stronger sender verification for business messaging.
All businesses sending Application-to-Person (A2P) SMS messages to Austrian mobile subscribers using an alphanumeric Sender ID must ensure their Sender IDs are registered and approved before enforcement begins.
Numeric sender IDs (VMNs and short codes) are not affected by this regulation.
What is a Sender ID?
A Sender ID is the alphanumeric name shown as the sender of an SMS message such as a brand or organisation name.
It is the unique identification that appears on the recipient’s mobile device as the sender of the message, enabling recipients to recognise the origin of the message and supporting trust.
Sender ID requirements
Sender IDs used in Austria must meet the following requirements:
Sender IDs must be between 1 and 11 characters long.
Sender IDs must contain at least one letter.
Sender IDs must clearly relate to the company, brand, service, or institution using them.
Sender IDs are case-sensitive. Variations in upper and lower case letters may be treated as separate Sender IDs (for example, BRAND and Brand).
Allowed characters are:
A-Z
a-z
0-9
Spaces
_
&
Umlauts (Ä, Ö, Ü, ä, ö, ü) and ß are not supported.
Dots (.) are not supported.
Generic Sender IDs without a clear company or brand connection may be rejected. Examples include:
Info
SMS Info
Delivery
OTP SMS
Sender IDs may not start with a + sign and may not contain spaces at the beginning or end.
Numeric-only Sender IDs and Sender IDs that may be confused with a phone number are not permitted.
A short justification is required for each Sender ID registration request.
Sender ID registration process
We manage the Sender ID registration process on your behalf, guiding you through each step to ensure a smooth experience.
Complete our Sender ID registration form where you provide the required Sender ID and business information.
Submit any supporting documentation requested.
We submit the Sender ID registration to the relevant Austrian operators for inclusion in the RTR registry.
RTR reviews the registration request.
Once approved, the Sender ID is added to the national registry and becomes eligible for use.
Registration review and activation
RTR reviews submitted Sender IDs and verifies that:
The Sender ID clearly identifies the business.
The organisation has the right to use the Sender ID.
Supporting information is accurate and complete.
Following approval, new registrations become active only after a mandatory waiting period. Businesses should allow sufficient time for registration, review, and activation before planning SMS campaigns.
What happens if a Sender ID is not registered?
If an alphanumeric Sender ID is not registered, messages will not be delivered to Austrian mobile subscribers.
Global trend
Austria is not alone. The sender ID registration approach reflects a broader international move towards sender verification:
Singapore – introduced in 2023.
Ireland – introduced in 2025.
Australia – introduced in 2026.
Spain – upcoming in 2026.
United Arab Emirates – alphanumeric Sender ID registration has been in place for many years.
Register your Sender IDs
Use our Sender ID registration form to submit your Austrian Sender ID registration request to Dotdigital.
We recommend submitting registration requests as early as possible to allow time for review and approval before enforcement begins.
Questions about Sender ID registration?
If you have questions about Sender ID registration or SMS sending in Australia, contact your Customer Success Manager or email us at support@dotdigital.com.