What the message is
The ATO does send SMS and email reminders about overdue lodgements. These are automated nudges generated because a return the ATO expected has not been lodged.
The distinguishing feature of a genuine reminder is what it does not contain. Real ATO reminders do not include links asking you to log in or to make a payment. They tell you something is outstanding and direct you to deal with it through the normal channels.
A genuine reminder is also not a penalty notice. Nothing has been charged at the point a reminder is sent. It is the ATO telling you a year is open before matters escalate.
Why you got it
Usually because a return has not been lodged for a year the ATO is expecting. Employers, banks and Centrelink report income data, so the ATO can see an open year without you having contacted it at all.
Reminders are also commonly received by people who thought they did not need to lodge, or who had an agent in an earlier year and assumed the arrangement continued. Neither is unusual and neither changes what needs to happen next.
And sometimes the message is simply not from the ATO. Scam messages copy this exact wording because it works: it creates urgency about something people already feel uneasy about.
How to check whether it is real
Do not tap the link, whatever the message says. Open myGov yourself and look at your ATO messages and your lodgment status there. If a year is genuinely outstanding, you will see it in your own account, and nothing is lost by taking the slower route.
The ATO never asks for payment by gift card or cryptocurrency, and it does not ask you to pay through a link in an SMS. A message doing any of those things is not from the ATO.
If the message turns out to be genuine, the position it describes is still ordinary and fixable. If it does not appear anywhere in myGov, ignore the message and delete it.
What to do now
Lodge first. Lodging the outstanding return resolves the reminder. There is nothing to reply to and no form to submit in response to the message itself - the flag clears when the year is lodged and assessed.
Then deal with penalties and debt. If the assessment results in tax payable, that is when a payment plan or a penalty remission request comes into play. Where the year results in a refund, penalties are generally not applied to individuals at all.
If you are not certain how many years are open, a free assessment answers that from the ATO's own records rather than from memory, and gives you a fixed fee to clear whatever is outstanding. If the reminder relates to activity statements rather than income tax, see Activity Statement 001 overdue.
Frequently asked questions
Does the ATO really send SMS about overdue tax returns?
Yes. The ATO sends SMS and email reminders about overdue lodgements. Genuine reminders do not contain links asking you to log in or make a payment.
How do I know if the message is a scam?
Check it in myGov rather than through the link. The ATO never asks for payment by gift card or cryptocurrency, and never asks you to pay through a link in an SMS.
Have I already been fined if I got this message?
No. A genuine reminder is a prompt, not a penalty. It is telling you a lodgement is outstanding so you can deal with it.
Do I need to reply to the SMS?
No. Lodging the outstanding return is what resolves it. There is nothing to reply to in the message itself.
Other ATO letters explained
General information only, current at the last reviewed date above. It is not personal tax advice, and your own outcome depends on your circumstances.

