SMS Guidelines for Australia
MCC: 505
Dial code: 61
The Australian Communications and Media Authority (ACMA) has introduced new requirements for alphanumeric sender IDs under the Telecommunications (SMS Sender ID Register) Industry Standard 2025, effective from 1 July 2026.
Under the new framework, alphanumeric sender IDs used for messaging traffic sent to Australia must be registered with the ACMA Sender ID Register.
What’s changing
All sender IDs must be registered with the ACMA Sender ID Register.
Existing registrations under the current carrier-based system will no longer be valid.
Messages sent using unregistered sender IDs will be transmitted with the sender ID “Unverified”.
Sender ID requirements:
Your sender ID must be clearly linked to your business and meet ACMA requirements. Acceptable sender IDs include:
Your registered business name (or a clear abbreviation);A registered trademark; or
A domain name that you own.
If your sender ID does not directly match one of the above, you must provide supporting evidence demonstrating its connection to your business, such as branding usage, domain ownership, or another verifiable association.
If the registration is being made on behalf of a customer, a signed Letter of Authorisation (LOA) must also be provided confirming the authority to submit the registration.
What you need to do
Please complete the attached form and return it to alpha_sender_id@telnyx.com, together with a copy of your business registration. Telnyx will submit the sender ID registration on your behalf via the ACMA portal. Once the registration has been submitted, you will be required to confirm it before it becomes effective.
You'll need to provide the appropriate contact details depending on your organisation type:
Entity Contact (for ACMA confirmation) — for companies with an Australian Business Number (ABN)
This contact will receive a confirmation request from ACMA and must be able to access the ACMA portal to complete the registration. They will require a digital myID to complete the registration. They must also be listed as an authorised contact on the ABR (or approved by one). If your organisation's authorised contacts on the ABR are not up to date, this contact will not be able to access the register.
You can check or update your organisation's authorised contacts on the ABR.
Senior Representative (for international companies without an ABN)
The contact provided must be a senior representative of the company — such as a director, officer, or other individual who would appear on official company registration documents. We use a third-party vetting service to verify that this person is a duly authorised representative of the company on behalf of ACMA.
If you have previously registered a sender ID with Telnyx, we will contact you directly with the next steps.
After 1 July 2026, messages sent using sender IDs that have not completed registration will be transmitted with the sender ID "Unverified" until the registration process has been completed.
Additional recommendations:
Consent (Proof for Opt-in) should be obtained before sending any communications, i.e. Marketing SMS
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.