How to register for GST in Australia (2025)

What is GST and who needs to register?

In Australia, Goods and Services Tax (GST) is a 10% tax on most goods and services.

If your small business earns $75,000 or more in GST turnover (or $150,000 for non-profit organisation), you are legally required to register within 21 days of reaching the threshold.

Whether you’re a sole trader, small business owner, or company director, this guide will help you to complete the registration process clearly and quickly.

Why does GST Registration matter?

• It’s required by law: If you earn above the threshold and don’t register, penalties apply.
• It affects your cash flow: You’ll collect GST on sales and pay it to the ATO, but you may be able to claim GST on eligible business expenses.
• It builds trust: Being registered can make your business appear more established to clients, suppliers and partners

Even if your GST turnover is below $75,000, voluntary registration may benefit you if you frequently incur business expenses with GST.

Who must register for GST?

You must register for GST if:

• Your GST turnover is $75,000+ per year (or $150,000+ for non-profit organisation);
• You expect GST turnover to exceed the threshold in your first year;
• You provide taxi, limousine, or ride-sourcing services (e.g. Uber), regardless of your GST turnover; or
• You want to claim fuel tax credits for your business.

If you register voluntarily, you generally need to stay registered for at least 12 months.

How do you register for GST in Australia?

To register, you’ll need an Australian Business Number (ABN). You can register via:

• Online: Through Online Services for Business (ATO Business Portal using myGovID)
• When applying for your ABN via the Australian Business Register
• By calling the ATO on 13 28 61
• With help from a registered tax or BAS agent

Once registered, you’ll get:

• A confirmation notice with your GST details
• The effective date of your registration
• Your ABN details (if you didn’t already have one)

You only need one GST registration per ABN, even if multiple businesses operate under the same ABN (but you can list different trading names if it makes accounting easier).

If you have businesses with multiple related entities, you may register as a GST group or branch).

How do you register an ABN for GST?

If you’re starting a business as a sole trader, partnership or company, you can apply for your ABN and GST registration at the same time. The online Australian Business Register (ABR) form will ask if you expect to exceed the GST turnover threshold, if yes, you can register immediately.

You can also register voluntarily if claiming GST credits makes sense for your situation.

All businesses operating under one ABN will fall under a single GST registration.

How do you register a company for GST?

When setting up a new company, you can apply for an ABN and Tax File Number (TFN) at the same time and choose to register for GST during the process. If the company already has an ABN, you can add GST registration later through the ATO’s online services.

How much does it cost to register for GST?

There is no fee for registering for GST with the ATO. If you use a tax or BAS agent, they may charge a service fee. This is often chosen by businesses that require professional help on managing their registrations or BAS obligations.

How long does GST registration take?

• If you already have an ABN and you register online, approval can be within minutes or a couple of business days.
• Phone or agent applications follow a similar timeline.
• If you’re applying for an ABN and GST at once, processing time can take up to 28 days, though it’s often quicker.

How do you work out your GST turnover?

Your GST turnover is your total business income, excluding:

• GST included in your sales
• Sales to associates (e.g. relatives or related entities)
• Sales not connected with the enterprise
• Input-taxed sales
• Certain overseas or non-payment transactions

You calculate it using:

• Current turnover: This month plus the previous 11 months; and
• Projected turnover: This month plus the next 11 months

If either of the above exceeds the threshold, you must register for GST.

Example:

Barry sells car parts. At the end of May, his gross income for the month was $2,560. Adding this to the previous 11 months, his GST turnover is $31,170, which is under the threshold. However, Barry also needs to calculate his projected turnover for the coming months. If he expects this to reach or exceed $75,000, he must register for GST within 21 days.

What happens if you don’t register for GST?

If you fail to register when required, the ATO can:

• Ask you to pay GST for past sales, even if you didn’t charge customers for it
• Apply penalties and interest
• Backdate your registration up to four years (or even longer if there’s evidence of fraud, evasion, or deliberate avoidance)

Backdated registration means you’ll need to account for GST on previous sales and possibly amend past BAS lodgements.

Are there any special GST registration cases?

Non-residents: Some overseas businesses need to register if selling taxable goods/services in Australia. Identity checks differ for these cases.

GST groups: Related entities can register as one GST group to simplify reporting as long as it satisfies certain requirements

GST branches: Large businesses may register separate branches if it suits their accounting.

Follow the links to discover more on the ATO website.

FAQs

How do I register for GST in Australia?

You can register through the ATO Business Portal using myGovID, during an ABN application, by calling the ATO, or through a registered tax or BAS agent.

How do I register an ABN for GST?

The ABN application includes an option to register for GST, so you can complete both at once.

How much does it cost to register?

There’s no cost to register directly. Agent fees may apply if you use one.

How long does it take?

Online registration is often instant, but it can take a few business days. If applying for an ABN and GST together, expect up to 28 days.

What happens if I don’t register?

The ATO may backdate your registration and charge GST on past sales, with penalties and interest.

Can I backdate my registration?

Yes, for up to four years unless fraud or evasion is involved.

Do I need to register every business separately?

No. All businesses under one ABN share the same GST registration.

How do I register a company for GST?

When applying for a company ABN, you can select GST registration at the same time. If the company already has an ABN, you can register for GST later using the ATO portal.

What should you do next after registering for GST?

If you’ve passed the GST turnover threshold, registering for GST is required by law. It’s also a smart move for businesses that claim GST credits on large purchases.

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Disclaimer: This information is general in nature and does not constitute legal, tax, or financial advice. While we’ve taken care to ensure the accuracy of this content at the time of publication, rules and regulations may change. For advice specific to your business or circumstances, please consult a registered tax agent, accountant, or the Australian Taxation Office (ATO).