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GST

GST Registration Threshold Australia — When You Must Register

When businesses must register for GST in Australia, the $75,000 registration threshold, voluntary registration, and what to do when you reach the threshold.

Updated June 2026·Written & reviewed by a CPA-qualified accountant·Based on public ATO guidance·General information only
Independent guide: Based on publicly available ATO guidance — not affiliated with the ATO. Tax law changes frequently — for your specific situation, consult a registered tax agent.

Frequently Asked Questions

When do I have to register for GST in Australia?

You must register for GST if your business has a GST turnover (gross income from sales) of $75,000 or more in any 12-month period, or if you expect to reach that threshold. The threshold is $150,000 for non-profit organisations.

Should I register for GST voluntarily if I am under the threshold?

Voluntary registration can make sense if your customers are businesses (they can claim your GST back), you have significant GST expenses you want to claim, or you want to appear more established. The downside is the administrative obligation to lodge BAS.

How long do I have to register for GST after reaching the threshold?

You must register within 21 days of becoming aware you have reached or will reach the $75,000 threshold. If you register late, you are liable for GST on all taxable supplies from the date you should have registered.

What is a BAS and when do I need to lodge one?

A Business Activity Statement (BAS) reports your GST collected and paid to the ATO. Most small businesses lodge quarterly. You must lodge even if the figures are zero. The ATO may automatically put you on monthly lodgement if your turnover exceeds $20 million.

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General information only. This guide provides general information about Australian tax law and does not constitute personal tax advice. Tax laws change and individual circumstances vary. Always consult a registered tax agent (registered with the Tax Practitioners Board) for advice specific to your situation. Taxplain is not a registered tax agent.