How to send bulk SMS in Australia

1. Choose an SMS provider

Compare the published price per message at the monthly volume you expect to send, because that price falls as monthly volume rises. Our price comparison ranks every provider that publishes an Australian rate at 1,000, 15,000, 125,000 and 250,000 messages a month.

Check whether you need two-way replies, email to SMS or an API before you commit to any provider. Bulk SMS needs no software installed: providers run a web app you log in to in a browser, an API for developers, and in many cases email to SMS.

2. Get consent for every number

Get consent from every person on your list before you send them a single commercial message. The Spam Act 2003 governs commercial text messages in Australia, and the ACMA enforces it. Every commercial message needs consent from the recipient, express or inferred, and you have to be able to show it.

Remember that the obligations fall on the business sending the message, not on the SMS provider, and that choosing a compliant provider does not move the duty.

Our guide to the Spam Act covers the consent rules in more detail.

3. Decide how your message will show who sent it

Decide between a sender ID and a number before you write a word of the message. A sender ID is your business name shown at the top of a text instead of a number, and it runs 2 to 11 characters. A sender ID cannot receive replies, so send from a number when you want recipients to reply.

Choose between the two kinds of number. A dedicated virtual mobile number carries a monthly fee on top of the message rate, and it stays the same across campaigns. A shared number is usually included at no extra cost, though the number can change.

Register your sender ID on the ACMA SMS Sender ID Register through each SMS provider you send with, a requirement since 1 July 2026. Registration is open. An unregistered sender ID is replaced with the word "Unverified", and the message is still delivered.

4. Write the message

Identify your business in the message and give accurate contact details, because every commercial message must clearly identify who sent it. Add a functional unsubscribe, commonly a line such as "Reply STOP to opt out". The law requires a working unsubscribe, and the exact wording is a convention rather than a legal form. Do not send passwords, full card numbers or health details in a text, because a standard SMS is not end-to-end encrypted.

Count your characters before you send anything. A single SMS holds 160 characters when every character is in the standard GSM-7 character set of plain letters, numbers and common punctuation. The whole message switches to UCS-2 encoding when it contains any character outside that set, such as an emoji, many accented letters or curly quotation marks. A single SMS holds 70 characters in UCS-2.

Expect a longer message to travel as linked parts. Each part holds 153 characters in GSM-7, or 67 in UCS-2, because some space in each part carries the information that joins them back together on the phone. Providers count each part of a long message as one message when they charge. Some GSM-7 characters count as two: the euro sign, square brackets, curly braces, the backslash, the tilde, the caret and the vertical bar.

5. Upload your list

Add your recipients in the provider's web app, which you will often do by uploading a spreadsheet file of mobile numbers. Developers can add recipients through the provider's API instead.

A list of staff goes into the web app in the same way as a list of customers.

6. Send a test, then send or schedule

Send the message to your own phone first, before anything goes to the list. The test shows how the message looks on a real phone and how many parts it uses, which is the number of messages you will pay for. Trim the wording and test again when the message runs longer than you want.

Send the campaign to the full list once the test message satisfies you. The web app sends it now or schedules it for later.

7. Check delivery and handle opt-outs

Check the delivery reports once the campaign has gone out to your list. The provider reports whether each message was delivered, using the delivery receipt the mobile network returns, and campaign reports are built from those receipts.

Act on every opt-out that comes back. Honour each unsubscribe within 5 working days, and keep the unsubscribe live for at least 30 days after the message is sent. The law sets both timeframes.