ACMA SMS Sender ID Rules
Text messaging has become one of the fastest and most effective ways for client-facing businesses to stay in touch — confirming appointments, sending reminders, sharing document links, or promoting an event. But if your business sends branded text messages and you haven't registered with the Australian Communications and Media Authority's (ACMA) new SMS Sender ID Register, there's a good chance your clients are already seeing those messages labelled "Unverified."
What's changed
From 1 July 2026, ACMA's SMS Sender ID Register came into effect. It was introduced to combat the growing problem of SMS impersonation scams by verifying the identity of businesses and organisations that send text messages under a branded sender ID — your business name, rather than a mobile number. Any branded sender ID that isn't registered is now automatically labelled "Unverified" and grouped alongside other unverified traffic, including genuine scam messages. There's no grace period, so if your business hasn't registered yet, this may already be affecting how your messages are received.
Why it matters for client trust
For any business that runs on client relationships — law firms very much included — trust is everything. Clients receive text messages containing appointment reminders, requests for information, document signing links and payment notifications. If those messages are grouped with unverified senders, clients may be less likely to open them, click through, or act on them at all. Beyond the anti-scam intent, registering your sender ID is also a simple way to reinforce your credibility and make sure important communications are recognised as genuinely yours.
What to do now
The good news is that registering is still straightforward, even after the deadline has passed:
Identify whether your business sends SMS using a branded sender ID rather than a mobile number.
Speak to your SMS provider, CRM, practice management software or marketing automation platform about registering your sender ID — many providers can register on your behalf or point you to the process.
Check that your Australian Business Register (ABR) details are current, particularly your authorised contact and service-of-notice email addresses, since these are used to verify your registration.
Review every system that sends texts on your behalf, including booking platforms, client communication tools and marketing automation software — each sender ID needs to be registered individually.
If your business uses more than one sender ID, make sure each one is covered.
ACMA already has form on this — and the fines are real
To be clear: failing to register your sender ID doesn't itself trigger a fine — the immediate consequence is the "Unverified" label. But the underlying obligation it's designed to reinforce, properly identifying yourself when you text customers, is exactly the kind of thing ACMA has already handed out multi-million dollar penalties for under the Spam Act 2003. A few recent examples:
TAB/Tabcorp was fined $4,003,270 in April 2025 after an ACMA investigation found thousands of SMS and WhatsApp messages to VIP customers lacked adequate sender information or a working unsubscribe option, with some sent without consent at all.
TAB/Tabcorp was fined again in July 2026, this time $2.7 million, for telemarketing calls without proper caller ID and for continuing to email and text customers who had already unsubscribed.
Betfair was fined $871,660 in July 2025 for sending marketing messages without consent and without a functional unsubscribe link.
Commonwealth Bank was fined $7.5 million in 2024, the largest spam penalty issued to date, after sending over 170 million marketing messages without proper consent or unsubscribe mechanisms.
Pizza Hut was fined $2.5 million in 2024 for more than 10 million non-compliant marketing messages sent without consent.
The common thread across all of these is basic sender identification, consent and unsubscribe hygiene — the same fundamentals the Sender ID Register exists to shore up. If your business is at risk of showing up as "Unverified," it's a good moment to check the rest of your SMS and email compliance too, not just the registration itself.
The bigger picture
This change is a timely reminder that clients are becoming more cautious about digital communications generally, and that trust, transparency and compliance in how you communicate directly affect whether your messages get seen, opened and acted on. Registering a sender ID might sound like a small administrative task, but for a business built on relationships, it's one worth doing properly — and promptly.
Key takeaways
ACMA's SMS Sender ID Register took effect on 1 July 2026 — if you haven't registered a branded sender ID, your texts are likely already labelled "Unverified."
There is no grace period, so register as soon as possible.
Confirm your ABR details are accurate and current.
Audit every platform that sends SMS on your business's behalf.
Keep complying with the Spam Act for all marketing messages — ACMA has fined businesses (including TAB, twice) millions of dollars for exactly these kinds of sender ID, consent and unsubscribe failures.
If you run an SME and want a hand thinking through your client communications, privacy obligations or broader compliance risk, our team can help. Get in touch with Connected Legal & Commercial for a chat.
Book a free 15-minute call to discuss your situation.
Connected Legal + Commercial is a Sydney-based commercial law firm. This article is general information only and does not constitute legal advice. For advice specific to your situation, please contact us.