SMS Guidelines for Austria including MCC and Dial Code. Get more messaging details here.
SMS Guidelines for Austria
MCC: 232
Dial Code: 43
The Austrian Regulatory Authority for Broadcasting and Telecommunications (RTR) has introduced new requirements for alphanumeric Sender IDs under § 5b KEM-V 2009 (10th amendment), effective from 1 October 2026.
Under the new framework, alphanumeric Sender IDs used for messaging traffic sent to Austria must be registered in the public Sender ID directory maintained by RTR. The registry has been open for registrations since 1 July 2026.
What's changing
- All alphanumeric Sender IDs must be registered in the RTR Sender ID directory.
- From 1 October 2026, unregistered alphanumeric Sender IDs will be blocked by Austrian operators and messages will no longer be delivered to Austrian recipients.
- To meet the deadline, registration information must be submitted by 16 September 2026, as RTR requires 14 days for processing and review.
Who needs to register?
You must register your Sender ID if you send any type of SMS traffic to Austria using an alphanumeric Sender ID. This applies to all message types, including:
- OTP and authentication messages
- Customer notifications
- Delivery updates
- Appointment reminders
- Marketing messages
- Transactional messages
- Service alerts
- Information messages
The message type does not change the requirement. If an SMS is sent to Austria with an alphanumeric Sender ID, the Sender ID must be registered.
Sender ID requirements
Your Sender ID must be clearly linked to your business and meet RTR requirements. Sender IDs must:
- Be 1–11 characters long and contain at least one letter
- Use only the following characters: A–Z, a–z, 0–9, +, -, &, _, and spaces
- Spaces are allowed inside the Sender ID, but not at the beginning or end
- Not contain umlauts, "ß", or unsupported special characters
- Clearly relate to the company, brand, or service using it
Generic Sender IDs such as "Info", "News", or "Delivery" may be rejected if they do not clearly connect to the registered company, brand, or service. A maximum of 40 alphanumeric Sender IDs per holder is allowed for Austria.
Registration requirements
To register an alphanumeric SMS Sender ID for Austria, you must provide the following:
- Customer or company name
- Legal entity name
- Company address
- Country code
- Contact email
- Sender ID (the exact alphanumeric string)
- Reason or justification for using the Sender ID — must be provided in German. This is a public field in the directory and should describe the legitimate connection between the Sender ID and the owner (e.g. brand name, trademark, or service description)
- Confirmation that the Sender ID is connected to the company, brand, or service
- Austria SMS traffic use case
If the registration is being made on behalf of a customer, a signed Letter of Authorisation (LOA) must also be provided, on the owner's letterhead, confirming the authority to submit the registration and clearly referencing the Sender ID string.
All registered Sender IDs and holder information are publicly visible in the RTR Open Data register.
What you need to do
Please complete the registration form and return it to alpha_sender_id@telnyx.com, together with the required information listed above. Telnyx will submit the Sender ID registration on your behalf to RTR.
Before submitting, make sure you have:
- Listed all alphanumeric Sender IDs used for SMS traffic to Austria
- Checked that each Sender ID follows the length and character rules
- Confirmed that each Sender ID contains at least one letter
- Confirmed that each Sender ID clearly relates to your company, brand, or service
- Added a short justification for why each Sender ID is used
- Checked that all company and holder information is correct and up to date
The public RTR directory can be searched at https://data.rtr.at/pages/open-data/tk-sms to check existing registrations by Sender ID or registered owner.
What happens if a Sender ID is not registered?
From 1 October 2026, unregistered alphanumeric Sender IDs will be blocked and SMS messages using them will no longer be delivered to Austrian recipients. This applies to all SMS traffic types — authentication, alerts, notifications, reminders, marketing, and all other customer or user SMS communication flows.
Additional recommendations
Consent (Proof for Opt-in) should be obtained before sending any marketing communications.
Traffic should include clear Opt-Out options.
Please make sure to always refer to our Acceptable Use Policy for Messaging.
For more information on Alpha Sender ID registration kindly reach out to alpha_sender_id@telnyx.com.