Getting the basics right protects your brand, your deliverability and your budget. This is a plain-English overview of what applies.
The three rules in every commercial message
Australian marketing SMS is regulated under the Spam Act 2003, overseen by the Australian Communications and Media Authority (ACMA). Three requirements apply to every commercial message.
1. Consent
You must have the recipient’s consent before sending a commercial message. Consent can be express — someone has clearly opted in — or, in limited cases, inferred from an existing relationship where the message is directly relevant to it.
The regulator’s clear preference is express consent, because it removes any doubt. Inferred consent is a narrow exception, not a default. Whichever applies, you should keep a record of how and when consent was obtained.
2. Identify yourself
Every commercial message must clearly identify the business that authorised it, using your correct legal name, or your business name and ABN. Your identifying details must stay accurate for at least 30 days after the message is sent. This obligation remains yours even when another provider sends the message on your behalf.
3. A working way to opt out
Every commercial message must include a functional way to unsubscribe. It has to be simple and low or no cost — a reply such as “Reply STOP to opt out” is acceptable. You cannot require someone to log in or hand over extra personal information to opt out. Once someone opts out you must stop sending to them promptly, and the opt-out facility must keep working for at least 30 days after the message.
ACMA enforces these rules with substantial penalties. Australian businesses across banking, retail, betting and other sectors have paid fines running into the millions for sending messages without proper consent, or without a working unsubscribe option. A missing opt-out link or an unverified consent record is not a technicality — it is the exact failure the regulator has repeatedly acted on.
The newer rule: registering your sender ID
There is now an additional requirement specific to SMS. From 1 July 2026, businesses using a branded sender ID — your organisation’s name shown at the top of the message instead of a phone number — must have that sender ID registered on the ACMA SMS Sender ID Register.
The register exists to stop scammers impersonating trusted brands in text messages. Messages sent using an unregistered branded sender ID are labelled “Unverified” by carriers, and may be blocked. That label sits next to your name in the recipient’s message list, which undermines exactly the trust a branded sender ID is meant to build.
We can assist you to register your sender ID. If you use, or plan to use, your business name as the sender on Australian SMS, this needs to be in place.
A note on alpha headers and replies
A branded (alphanumeric) sender ID has one practical limitation worth planning around: if it is anything other than a valid mobile number, it cannot receive replies. If your message asks the recipient to respond, you need a reply-capable number rather than a branded name, or a clear alternative way to respond such as a link or a phone number in the message. If you need a suitable reply number that also covers opt-out options, talk to us and we can supply one.
A short pre-send compliance check
- Do we have express (or valid inferred) consent for everyone on this list?
- Can we show when and how that consent was obtained?
- Does the message identify our business correctly?
- Is there a clear, low-cost opt-out, and will we action opt-outs promptly?
- If we use a branded sender ID, is it registered?
- If we expect replies, are we using a reply-capable number?
Meeting these does not only keep you compliant. It also tends to improve results, because messages people agreed to receive, from a sender they recognise, are the ones that get read.